Shallow over rock

A spade that stops at twenty centimetres. Whatever the topsoil is made of, the constraint here is that there is not much of it.

Not sure this is you? Four hand tests will settle it — the squeeze test alone distinguishes the main textures in about a minute.

What it is

Texture: The balanced mixture every soil description uses as its reference point: holds moisture without waterlogging, and works over a long season.
Sourced guidanceDepends on conditionslow confidence
Applies when: The texture of the thin layer above the rock varies with the rock beneath — loamy over sandstone, clayey over shale, chalky over chalk. It is recorded as loam because that is the commonest case, and the depth rather than the texture is what governs the advice.
Soilscapes — Cranfield University, National Soil Resources Institute: Shallow soil associations
Checked 2026-08-13
pH: Not established
Sourced guidancelow confidence
Entirely dependent on the parent rock, which is not knowable from the depth. A soil test is the only way to establish it, and this record declines to guess.
Soilscapes — Cranfield University, National Soil Resources Institute: Soil reaction
Checked 2026-08-13
Drainage: Free-draining
Sourced guidanceDepends on conditionslow confidence
Applies when: Free-draining where the rock beneath is permeable, and waterlogged where it is not — a thin soil over impermeable rock has nowhere for water to go and sits wet.
Soilscapes — Cranfield University, National Soil Resources Institute: Drainage classes
Checked 2026-08-13
Moisture: Dries out quickly
source
Horticultural consensusmoderate confidence
Soilscapes — Cranfield University, National Soil Resources Institute: Available water capacity
Checked 2026-08-13
Structure: Shallow over rock
source
Horticultural consensusmoderate confidence
Soilscapes — Cranfield University, National Soil Resources Institute: Soil depth classes
Checked 2026-08-13
Organic matter: low
Sourced guidancelow confidence
James Hutton Institute — The James Hutton Institute: Soil organic matter
Checked 2026-08-13
Working depth: 10–25 cm
source
Sourced guidancemoderate confidence
Soilscapes — Cranfield University, National Soil Resources Institute: Soil depth classes
Checked 2026-08-13
Holds nutrients: poor
source
Sourced guidancemoderate confidence
Agriculture and Horticulture Development Board — AHDB: Shallow soils
Checked 2026-08-13

Described viewA vertical cut through shallow soil showing perhaps twenty centimetres of topsoil sitting directly on bedrockThe constraint here is depth, and it is only visible in a hole.

What it is good at

Every soil grows something better than loam does, and a description that lists only problems is a complaint rather than intelligence.

Warms very quickly in spring, because there is little soil mass to heat, so early salads and shallow-rooted crops are ready sooner than on deep ground.
source
Sourced guidancemoderate confidence
- Royal Horticultural Society: Shallow soils
Checked 2026-08-13
Shallow-rooted crops — lettuce, radish, spring onions, most herbs — are entirely unaffected by the limitation and crop as well as anywhere.
source
Sourced guidancemoderate confidence
- Royal Horticultural Society: Shallow soils
Checked 2026-08-13

What goes wrong on it

Long root crops fork or stop when they reach the rock, and deep-rooted perennials and fruit trees have nowhere to anchor.
source
Horticultural consensusmoderate confidence
- Royal Horticultural Society: Growing carrots
Checked 2026-08-13
There is very little water held in reserve, so a dry fortnight has the effect a dry month would have on deep soil.
source
Horticultural consensusmoderate confidence
- Soilscapes — Cranfield University, National Soil Resources Institute: Available water capacity
Checked 2026-08-13

The thing most worth knowing

Depth is the one property that can genuinely be added, and only upwards. A 30 cm raised bed on shallow ground turns an impossible site into an ordinary one.

What grows on shallow over rock

Computed across 223 plants by comparing each one's recorded requirements against this soil's recorded characteristics. Every verdict can be taken apart into the criteria that produced it, and a recorded horticultural fact overrides the computation where one exists.

Prefers this soil110

Plant	Why
Agapanthus	Shallow over rock suits Agapanthus as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Aloe vera	Shallow over rock suits Aloe vera as it stands: The free drainage is exactly what it wants. It stands dry conditions better than most, which this soil will test.
Amelanchier	Shallow over rock suits Amelanchier as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Armand clematis	Shallow over rock suits Armand clematis as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Asparagus	Shallow over rock suits Asparagus as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Bay	Shallow over rock suits Bay as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Bearded iris	Shallow over rock suits Bearded iris as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Berberis	Shallow over rock suits Berberis as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Bird of paradise	Shallow over rock suits Bird of paradise as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Blue fescue	Shallow over rock suits Blue fescue as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Borage	Shallow over rock suits Borage as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Buddleja	Shallow over rock suits Buddleja as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Californian lilac	Shallow over rock suits Californian lilac as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Chamomile	Shallow over rock suits Chamomile as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Chicory	Shallow over rock suits Chicory as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Chilli pepper	Shallow over rock suits Chilli pepper as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Chives	Shallow over rock suits Chives as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Christmas box	Shallow over rock suits Christmas box as it stands: Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Cotoneaster	Shallow over rock suits Cotoneaster as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Crab apple	Shallow over rock suits Crab apple as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Crocosmia	Shallow over rock suits Crocosmia as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Crocus	Shallow over rock suits Crocus as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Curry leaf	Shallow over rock suits Curry leaf as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Daffodil	Shallow over rock suits Daffodil as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Deutzia	Shallow over rock suits Deutzia as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Dill	Shallow over rock suits Dill as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Dragon tree	Shallow over rock suits Dragon tree as it stands: The free drainage is exactly what it wants. It stands dry conditions better than most, which this soil will test.
Echeveria	Shallow over rock suits Echeveria as it stands: The free drainage is exactly what it wants. It stands dry conditions better than most, which this soil will test.
Echinacea	Shallow over rock suits Echinacea as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Epimedium	Shallow over rock suits Epimedium as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Escallonia	Shallow over rock suits Escallonia as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Fennel	Shallow over rock suits Fennel as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Firethorn	Shallow over rock suits Firethorn as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Forsythia	Shallow over rock suits Forsythia as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Foxglove	Shallow over rock suits Foxglove as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
French bean	Shallow over rock suits French bean as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Garlic	Shallow over rock suits Garlic as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Garlic chives	Shallow over rock suits Garlic chives as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Gladiolus	Shallow over rock suits Gladiolus as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Globe artichoke	Shallow over rock suits Globe artichoke as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Golden-scaled male fern	Shallow over rock suits Golden-scaled male fern as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Grape hyacinth	Shallow over rock suits Grape hyacinth as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Hard shield fern	Shallow over rock suits Hard shield fern as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Hardy cyclamen	Shallow over rock suits Hardy cyclamen as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Hardy geranium	Shallow over rock suits Hardy geranium as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Hart's tongue fern	Shallow over rock suits Hart's tongue fern as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Haworthia	Shallow over rock suits Haworthia as it stands: The free drainage is exactly what it wants. It stands dry conditions better than most, which this soil will test.
Hawthorn	Shallow over rock suits Hawthorn as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Hebe	Shallow over rock suits Hebe as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Hellebore	Shallow over rock suits Hellebore as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Henry's honeysuckle	Shallow over rock suits Henry's honeysuckle as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Heuchera	Shallow over rock suits Heuchera as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Hippeastrum	Shallow over rock suits Hippeastrum as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Holly	Shallow over rock suits Holly as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Hoya	Shallow over rock suits Hoya as it stands: The free drainage is exactly what it wants. It stands dry conditions better than most, which this soil will test.
Hyacinth	Shallow over rock suits Hyacinth as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Hyssop	Shallow over rock suits Hyssop as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Ivy	Shallow over rock suits Ivy as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Jade plant	Shallow over rock suits Jade plant as it stands: The free drainage is exactly what it wants. It stands dry conditions better than most, which this soil will test.
Jerusalem artichoke	Shallow over rock suits Jerusalem artichoke as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Lamb's lettuce	Shallow over rock suits Lamb's lettuce as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Lavender	Shallow over rock suits Lavender as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Lemon balm	Shallow over rock suits Lemon balm as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Lemon thyme	Shallow over rock suits Lemon thyme as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Lemon verbena	Shallow over rock suits Lemon verbena as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Lily	Shallow over rock suits Lily as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Mahonia	Shallow over rock suits Mahonia as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Maidenhair spleenwort	Shallow over rock suits Maidenhair spleenwort as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Male fern	Shallow over rock suits Male fern as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Marjoram	Shallow over rock suits Marjoram as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Mexican feather grass	Shallow over rock suits Mexican feather grass as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Mexican orange blossom	Shallow over rock suits Mexican orange blossom as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Miscanthus	Shallow over rock suits Miscanthus as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Mock orange	Shallow over rock suits Mock orange as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Nerine	Shallow over rock suits Nerine as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Onion	Shallow over rock suits Onion as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Oregano	Shallow over rock suits Oregano as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Ornamental allium	Shallow over rock suits Ornamental allium as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Osmanthus	Shallow over rock suits Osmanthus as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Passionflower	Shallow over rock suits Passionflower as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Peony	Shallow over rock suits Peony as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Periwinkle	Shallow over rock suits Periwinkle as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Pothos	Shallow over rock suits Pothos as it stands: The free drainage is exactly what it wants. It stands dry conditions better than most, which this soil will test.
Rosemary	Shallow over rock suits Rosemary as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Rowan	Shallow over rock suits Rowan as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Sage	Shallow over rock suits Sage as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Salad burnet	Shallow over rock suits Salad burnet as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Salvia	Shallow over rock suits Salvia as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Savory	Shallow over rock suits Savory as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Shallot	Shallow over rock suits Shallot as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Silver birch	Shallow over rock suits Silver birch as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Snake plant	Shallow over rock suits Snake plant as it stands: The free drainage is exactly what it wants. It stands dry conditions better than most, which this soil will test.
Soft shield fern	Shallow over rock suits Soft shield fern as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Spider plant	Shallow over rock suits Spider plant as it stands: The free drainage is exactly what it wants. It stands dry conditions better than most, which this soil will test.
Spiraea	Shallow over rock suits Spiraea as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Star jasmine	Shallow over rock suits Star jasmine as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
String of hearts	Shallow over rock suits String of hearts as it stands: The free drainage is exactly what it wants. It stands dry conditions better than most, which this soil will test.
String of pearls	Shallow over rock suits String of pearls as it stands: The free drainage is exactly what it wants. It stands dry conditions better than most, which this soil will test.
Sweet pepper	Shallow over rock suits Sweet pepper as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Sweetcorn	Shallow over rock suits Sweetcorn as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Tarragon	Shallow over rock suits Tarragon as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Thyme	Shallow over rock suits Thyme as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Tiger flower	Shallow over rock suits Tiger flower as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Tulip	Shallow over rock suits Tulip as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Viburnum	Shallow over rock suits Viburnum as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Virginia creeper	Shallow over rock suits Virginia creeper as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Winter savory	Shallow over rock suits Winter savory as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
Wisteria	Shallow over rock suits Wisteria as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting.
Yew	Shallow over rock suits Yew as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. It stands dry conditions better than most, which this soil will test.
ZZ plant	Shallow over rock suits ZZ plant as it stands: The free drainage is exactly what it wants. It stands dry conditions better than most, which this soil will test.

Grows well here25

Plant	Why
Aglaonema	Aglaonema grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Broad bean	Broad bean grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Brussels sprouts	Brussels sprouts grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Chard	Chard grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Chinese money plant	Chinese money plant grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Christmas cactus	Christmas cactus grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Evergreen climbing hydrangea	Evergreen climbing hydrangea grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Fatsia	Fatsia grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Feather reed grass	Feather reed grass grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Heartleaf philodendron	Heartleaf philodendron grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Kale	Kale grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Kentia palm	Kentia palm grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Leek	Leek grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Lovage	Lovage grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Monstera	Monstera grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Moth orchid	Moth orchid grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Parlour palm	Parlour palm grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Peperomia	Peperomia grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Rose	Rose grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Rubber plant	Rubber plant grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Rudbeckia	Rudbeckia grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Snowdrop	Snowdrop grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Swiss cheese vine	Swiss cheese vine grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Syngonium	Syngonium grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Weigela	Weigela grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.

Works, with one condition80

These crop perfectly well here once one specific thing is dealt with. The condition is stated for each, and it is usually a single job rather than an ongoing one.

Plant	Why	What to do
Alocasia	Alocasia will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Anthurium	Anthurium will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Apple	Apple will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 60 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Apricot	Apricot will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 50 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Aubergine	Aubergine will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Basil	Basil will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Beetroot	Beetroot will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 30 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Blackberry	Blackberry will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 40 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Boston fern	Boston fern will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Broccoli	Broccoli will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Brunnera	Brunnera will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Bugle	Bugle will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Cabbage	Cabbage will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Calathea	Calathea will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Camellia	Camellia will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Canna	Canna will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Carrot	The root reaches rock and stops or forks. This is not a soil quality problem and cannot be improved away — the stones and the rock are the soil.recorded fact	A container at least 30 cm deep, or a raised bed of stone-free soil. Short-rooted cultivars in the ground will produce something; long-rooted ones will not.
Cauliflower	Cauliflower will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Celeriac	Celeriac will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Celery	Celery will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Chervil	Chervil will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Clematis	Clematis will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Climbing hydrangea	Climbing hydrangea will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Coriander	Coriander will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Courgette	Courgette will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Cucumber	Cucumber will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Dahlia	Dahlia will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Dieffenbachia	Dieffenbachia will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Endive	Endive will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Fig	Fig will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 45 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Fittonia	Fittonia will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Fuchsia	Fuchsia will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Gooseberry	Gooseberry will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 30 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Grape	Grape will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 60 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Honeysuckle	Honeysuckle will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Hosta	Hosta will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Hydrangea	Hydrangea will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Japanese forest grass	Japanese forest grass will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Japanese maple	Japanese maple will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Kohlrabi	Kohlrabi will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Lady fern	Lady fern will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Land cress	Land cress will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Lemongrass	Lemongrass will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Lettuce	Lettuce will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Loganberry	Loganberry will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 40 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Magnolia	Magnolia will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Mint	Mint will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Ostrich fern	Ostrich fern will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Pak choi	Pak choi will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Parsley	Parsley will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Parsnip	Parsnip will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 60 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Pea	Pea will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Peace lily	Peace lily will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Peach	Peach will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 50 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Pear	Pear will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 60 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Pieris	Pieris will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Plum	Plum will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 50 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Pumpkin	Pumpkin will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Quince	Quince will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 50 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Radish	Radish will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Redcurrant	Redcurrant will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 30 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Rhododendron	Rhododendron will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Rocket	Rocket will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Royal fern	Royal fern will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Runner bean	Runner bean will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Sedge	Sedge will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Shiso	Shiso will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Skimmia	Skimmia will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Sorrel	Sorrel will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Spinach	Spinach will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Spring onion	Spring onion will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Strawberry	Strawberry will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Swede	Swede will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Tayberry	Tayberry will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 40 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Thai basil	Thai basil will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Tuberous begonia	Tuberous begonia will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Turnip	Turnip will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Vietnamese coriander	Vietnamese coriander will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.
Whitecurrant	Whitecurrant will crop on shallow over rock, but one thing has to be dealt with first. It roots to about 30 cm and this soil offers roughly 25 cm before rock or hardpan.	Grow it in a deep container or a raised bed. The rooting depth is not something that can be added to the ground.
Winter squash	Winter squash will crop on shallow over rock, but one thing has to be dealt with first. It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering.	Water and mulch will carry it through. On this soil the watering is not optional in a dry spell, which is the difference between a crop and a failure.

Struggles here8

Struggles in the open ground here. That is not the same as impossible — a container or a raised bed of imported soil sidesteps almost all of these, and for several it is the standard way of growing them anyway.

Plant	Why
Blackcurrant	Blackcurrant struggles on shallow over rock: It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering. It roots to about 30 cm and this soil offers roughly 25 cm before rock or hardpan. A container or a raised bed of imported soil sidesteps the problem entirely.
Blueberry	Blueberries are shallow-rooted and would seem to suit shallow ground, but they need a consistently moist, acid root zone and a thin soil over rock delivers neither — it dries out between waterings and its pH follows whatever the rock beneath is. A container gives complete control over both, which is why nearly all garden blueberries are grown that way.recorded fact
Cherry	Cherry struggles on shallow over rock: It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering. It roots to about 50 cm and this soil offers roughly 25 cm before rock or hardpan. A container or a raised bed of imported soil sidesteps the problem entirely.
Melon	Melon struggles on shallow over rock: It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering. It roots to about 40 cm and this soil offers roughly 25 cm before rock or hardpan. A container or a raised bed of imported soil sidesteps the problem entirely.
Potato	Potato struggles on shallow over rock: It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering. It roots to about 45 cm and this soil offers roughly 25 cm before rock or hardpan. A container or a raised bed of imported soil sidesteps the problem entirely.
Raspberry	Raspberry struggles on shallow over rock: It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering. It roots to about 30 cm and this soil offers roughly 25 cm before rock or hardpan. A container or a raised bed of imported soil sidesteps the problem entirely.
Rhubarb	Rhubarb struggles on shallow over rock: It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering. It roots to about 45 cm and this soil offers roughly 25 cm before rock or hardpan. A container or a raised bed of imported soil sidesteps the problem entirely.
Tomato	Tomato struggles on shallow over rock: It has little drought tolerance and this soil dries out fast — it will check and bolt in the first dry spell without watering. It roots to about 45 cm and this soil offers roughly 25 cm before rock or hardpan. A container or a raised bed of imported soil sidesteps the problem entirely.

What is worth doing about it

Each of these states its ceiling as well as its effect, because every soil improvement is oversold somewhere and a gardener who knows where it stops does not keep going for another three years.

Raised beds

Works straight awayhigh effort

Lifts the root zone above the water table, so roots are in soil that drains even when the ground beneath does not. It also warms earlier in spring and gives rooting depth where there is rock or hardpan close to the surface.

source

Horticultural consensusmoderate confidence

Royal Horticultural Society: Raised beds

Checked 2026-08-13

What it will not do: It does not drain the ground underneath. A raised bed on waterlogged clay is a container sitting on a puddle: it works because the roots are above the problem, not because the problem is gone. Beds under about 20 cm deep achieve very little of this.

Deep beds and containers for root crops

Works straight awaymoderate effort

Gives a straight, stone-free run for a taproot to grow down. A forked carrot is a root that met an obstacle, and no amount of soil improvement removes the stones from a stony soil.

source

Sourced guidancehigh confidence

Royal Horticultural Society: Growing carrots

Checked 2026-08-13

What it will not do: It does nothing for the rest of the garden, and it is not a general fix — it addresses one specific failure of one group of crops. Sieving stones out of an open bed is possible and rarely worth the labour, as more work upwards each year.

Bulky organic matter

Two to five years of repetitionmoderate effort

Improves structure on every soil type: it binds sand into crumbs that hold water and nutrients, and opens clay so air and roots can get through. It also feeds the soil biology that maintains the structure once it exists.

source

Horticultural consensusmoderate confidence

Royal Horticultural Society: Improving soil
James Hutton Institute — The James Hutton Institute: Soil organic matter and structure

Checked 2026-08-13

What it will not do: It will not change what the soil is made of. Clay with twenty years of compost in it is well-structured clay, not loam, and it will still be sticky in a wet February. Nor does it meaningfully move pH.

Manure must be well rotted. Fresh manure scorches roots and robs nitrogen from the soil as it breaks down, and manure from an unknown source can carry residues of persistent broad-leaved herbicides that damage potatoes, tomatoes and beans for several seasons.

source

Sourced guidancehigh confidence

Royal Horticultural Society: Manure — aminopyralid contamination

Checked 2026-08-13

Surface mulch

Works straight awaylow effort

Slows evaporation from the surface, so a droughty soil holds what it is given for longer. It also suppresses annual weeds and protects the surface from the impact of heavy rain, which is what causes capping.

source

Horticultural consensusmoderate confidence

Royal Horticultural Society: Mulching

Checked 2026-08-13

What it will not do: It does not add water. Mulch applied to dry ground keeps it dry — the soil must be moist when the mulch goes on, which in practice means spring after rain rather than midsummer.

All ten interventions, compared, including the ones that do not apply here.

The other soils

Soil record reviewed 2026-08-14.