VegetabletuberStraightforward

Potato

Solanum tuberosum

Before you grow or eat this

Green potato tubers, sprouts, and all the above-ground parts of the plant contain glycoalkaloids — chiefly solanine — which cause gastrointestinal illness and, in quantity, neurological symptoms. Greening is caused by light exposure and indicates that glycoalkaloids have increased with it. Do not eat green tubers or sprouts: cut them out generously, and discard any tuber that is extensively green or tastes bitter. Store potatoes in the dark, and keep the fruits — small green tomato-like berries that appear after flowering — away from children.

Grown from seed tubers rather than seed, and organised around one decision: earlies or maincrop. Earlies are planted in spring, lifted young in early summer, and usually dodge blight entirely. Maincrops stay in the ground for months, yield far more, and are the ones blight takes. Potatoes are also the crop most worth growing in a container, because a bag of new potatoes is genuinely better than a bought one.

Position: Full sun
Water: high demand
Drainage: Free-draining
Grows to: 45–75 cm × 45–60 cm
Hardiness: H2
Harvest: June to October
Difficulty: Straightforward

Described view

Soil being drawn up around the stems of a row of potato plants with a hoe, forming a ridge along the row

August

Harvest

Potato’s year

Resolved for United Kingdom (general). Every window is stored against a climate event rather than a date, so a late frost pocket runs later than the band shows. What else August calls for.

Activity	J	F	M	A	M	J	J	A	S	O	N	D
Plant			March.	April.	May.
Harvest						June.	July.	August.	September.	October.

Names that cause confusion

sweet potato — An entirely different plant (Ipomoea batatas, in the bindweed family) with different growing requirements. Not a potato.

Timing that travels

The band above resolves this plant's windows into months for one region. These are the windows themselves, stored against a climate event rather than a date — which is the form that survives being carried to a colder garden, a frost pocket, or next year.

Plant
0–6 weeks after the soil becoming workable
source
Sourced guidancehigh confidence
- Royal Horticultural Society: Potatoes — when to plant
Checked 2026-08-13
First earlies go in first. Planting into cold wet soil gains nothing: the tubers simply sit there.

Conditions it needs

Light: Full sun
Direct sun: 6 hours a day or more
Frost: Half hardySourced guidanceDepends on conditions
Hardiness rating: H2 (RHS)
Grows best at: 15–20 °C
Soil: Loam, Sandy, Silt
Soil pH: 5–6.5Sourced guidanceDepends on conditions
Drainage: Free-draining
Water needs: high
Drought: poor tolerance
Waterlogging: poor tolerance
Heat: moderate toleranceHorticultural consensusDepends on conditions
Wind and exposure: moderate tolerance

Where these figures come from

LightSourced guidancehigh confidence

Royal Horticultural Society: Potatoes — position

Checked 2026-08-13

Direct sunHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

FrostSourced guidanceDepends on conditionshigh confidence

Applies when: The tubers underground survive frost; the emerged foliage is killed by it. A frosted plant regrows from the tuber but loses weeks.

Royal Horticultural Society: Potatoes — frost

Checked 2026-08-13

Hardiness ratingSourced guidancehigh confidence

Royal Horticultural Society: RHS hardiness ratings

Checked 2026-08-13

Grows best atHorticultural consensusmoderate confidence

University of Minnesota Extension — University of Minnesota: Growing potatoes in home gardens

Checked 2026-08-13

SoilSourced guidancehigh confidence

Royal Horticultural Society: Potatoes — soil

Checked 2026-08-13

Soil pHSourced guidanceDepends on conditionshigh confidence

Applies when: Potatoes tolerate more acid ground than most crops, and slightly acid soil reduces common scab — which is why they are not usually grown on freshly limed ground.

University of Minnesota Extension — University of Minnesota: Soil pH for vegetable crops

Checked 2026-08-13

DrainageHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

Water needsHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

DroughtHorticultural consensusmoderate confidence

Water matters most as the tubers begin to swell, around flowering.

Royal Horticultural Society: Potatoes — watering

Checked 2026-08-13

WaterloggingHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

HeatHorticultural consensusDepends on conditionsmoderate confidence

Applies when: Tuber formation slows markedly in prolonged heat above roughly 27 °C.

No external citation — see the evidence type above.

Checked 2026-08-13

Wind and exposureHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

On your soil

Computed by comparing this plant's recorded requirements against each soil's recorded characteristics. A recorded horticultural fact overrides the comparison where GrowingHQ holds one.

Soil	Verdict	Why
Heavy clay	Works, with one condition	Potato will crop on heavy clay, but one thing has to be dealt with first. It needs ground that drains, and this soil holds water. A plant that stays in the ground through winter with its roots in cold, saturated soil rots — which is what kills most of what fails on heavy ground, rather than the cold.Improve the drainage before planting — a raised bed, or bulky organic matter worked in over several seasons. Do not add sand to clay in small quantities; it makes the problem worse.
Sandy	Works, with one condition	Potato will crop on sandy, 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.
Chalky and alkaline	Works, with one condition	Potatoes crop on chalk, but alkaline, free-draining soil is exactly the condition that favours common scab — the corky patches on the skin. The tubers remain perfectly edible; the crop simply looks poor, which matters more to some growers than others.Water consistently through tuber formation, which is the single most effective control, and choose a scab-resistant cultivar. Do not lime before potatoes.
Loam	Prefers this soil	Loam suits Potato as it stands: The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. The soil holds moisture, which saves a great deal of watering. There is ample rooting depth for it.
Silty	Prefers this soil	Silty suits Potato as it stands: The free drainage is exactly what it wants. Silt is among the soils it is recorded as suiting. The soil holds moisture, which saves a great deal of watering. There is ample rooting depth for it.
Peaty and acid	Works, with one condition	Potato will crop on peaty and acid, but one thing has to be dealt with first. It needs ground that drains, and this soil holds water. A plant that stays in the ground through winter with its roots in cold, saturated soil rots — which is what kills most of what fails on heavy ground, rather than the cold.Improve the drainage before planting — a raised bed, or bulky organic matter worked in over several seasons. Do not add sand to clay in small quantities; it makes the problem worse.
Shallow over rock	Struggles here	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.
Made ground and urban soil	Prefers this soil	The traditional first crop on rough ground, and the reputation is deserved for a practical rather than a botanical reason: earthing up, and then digging the crop, works the top 30 cm thoroughly and adds organic matter as a side effect. Potatoes do not 'clean' the soil in any biological sense — the cultivation does the work — but on a compacted new-build garden the effect is real.

Not sure which you have? Four hand tests will settle it.

Space and spacing

Mature height: 45–75 cm
Mature spread: 45–60 cm
Rooting depth: 45–60 cm
Spacing: 30–38 cm apartSourced guidanceDepends on conditions
Row spacing: 60–75 cm

Where these figures come from

Mature heightHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

Mature spreadHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

Rooting depthHorticultural consensusmoderate confidence

USU Extension — Utah State University: Vegetable rooting depths

Checked 2026-08-13

SpacingSourced guidanceDepends on conditionshigh confidence

Applies when: About 30 cm for first earlies, 38 cm for maincrops, which need more room to bulk up.

Royal Horticultural Society: Potatoes — planting distances

Checked 2026-08-13

Row spacingSourced guidancehigh confidence

Royal Horticultural Society: Potatoes — planting distances

Checked 2026-08-13

Measured centre to centre. Plants set closer than this compete for light and water long before they look crowded, and the crowding cannot be undone once they are in.

In a container

Minimum volume: 30–40 litresSourced guidanceDepends on conditions
Minimum depth: 40 cm

Where the container figures come from

Minimum volumeSourced guidanceDepends on conditionshigh confidence

Applies when: Per two or three seed tubers. Earlies suit containers far better than maincrops.

Royal Horticultural Society: Potatoes in containers

Checked 2026-08-13

Minimum depthSourced guidancehigh confidence

Royal Horticultural Society: Potatoes in containers

Checked 2026-08-13

Depth is needed for earthing up as much as for rooting — the stem produces tubers along the buried section.

Where and how you can grow it

Each way of growing is assessed separately, and “not assessed” is a real answer rather than a gap we have filled in with a guess.

Method	Suitability	What it needs
Open ground	Well suited source Sourced guidancehigh confidence Royal Horticultural Society: Growing potatoes Checked 2026-08-13	Room to earth up along the row
Traditional dug bed	Well suited source Horticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13
Container	Well suited source Sourced guidancehigh confidence Royal Horticultural Society: Potatoes in containers Checked 2026-08-13	A 30–40 litre bag or tub; Two or three seed tubers per container; Consistent watering once the foliage is upFirst earlies in a bag are one of the best returns available to a grower with no ground at all.
Raised bed	Workable source Horticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13	At least 30 cm of soil depthWorkable rather than ideal: potatoes take up a lot of bed for a crop that is cheap to buy, and earthing up in a shallow bed is awkward.
Greenhouse	Workable source Horticultural consensusmoderate confidence Used to force a very early crop in bags, not as a season-long occupant. No external citation — see the evidence type above. Checked 2026-08-13
Polytunnel	Workable source Horticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13
Hydroponics	Marginal source GrowingHQ editorial positionmoderate confidence Potatoes form tubers along buried stem, which needs a deep medium that can be added to as the plant grows. Soilless systems can be built to do it and the result is an expensive way to grow one of the cheapest vegetables there is. GrowingHQ editorial synthesis — GrowingHQ Checked 2026-08-13
Aquaponics	Marginal source Sourced guidancehigh confidence Purdue Extension — Purdue University: Aquaponics — crop selection Checked 2026-08-13
Windowsill	Not suitable source Horticultural consensusmoderate confidence Far too large and too light-hungry. No external citation — see the evidence type above. Checked 2026-08-13

Growing it

PlantingPlant seed tubers about 12–15 cm deep with the shoots uppermost. Buy certified seed potatoes rather than planting supermarket ones, which may carry virus and are often treated to suppress sprouting.12–15 cm
Earthing upDraw soil up around the stems as they grow, to about 15 cm. This does two jobs: it gives the stem more buried length to form tubers along, and it keeps developing tubers out of the light — which is what stops them going green.
WateringWater thoroughly from the point the plants flower onwards. This is when the tubers swell, and it is the watering that decides the size of the crop.
ProtectionCover emerging shoots with fleece or draw soil over them if a late frost is forecast. Frosted foliage blackens and the plant has to start again.
FeedingPotatoes are hungry. Work in compost or well-rotted manure before planting and give a general fertiliser at planting time. Maincrops benefit from a second dressing as the tubers begin to bulk; earlies are lifted too soon to need one.

Where this guidance comes from

PlantingSourced guidancehigh confidence: Royal Horticultural Society: Potatoes — planting
Checked 2026-08-13
Earthing upSourced guidancehigh confidence: Royal Horticultural Society: Potatoes — earthing up
Checked 2026-08-13
WateringSourced guidancehigh confidence: Royal Horticultural Society: Potatoes — watering
Checked 2026-08-13
ProtectionHorticultural consensusmoderate confidence: Royal Horticultural Society: Potatoes — frost protection
Checked 2026-08-13
FeedingSourced guidancehigh confidence: Royal Horticultural Society: Potatoes — feeding
Checked 2026-08-13

Is it worth putting under cover?

Whether it will grow there is on the methods table above. This is whether the space is well spent, which is a different question and usually the one being asked.

Structure	What protection is worth	What decides it
Greenhouse	Extends the season source GrowingHQ editorial positionmoderate confidence What protection is worth for this crop, judged against the same standard as every other record in this file. GrowingHQ editorial synthesis — GrowingHQ Checked 2026-08-13	Earliness only. A bag of first earlies under cover gives new potatoes in May and is a poor use of the space for anything maincrop.Bags or deep pots, not the border
Polytunnel	Extends the season source GrowingHQ editorial positionmoderate confidence What protection is worth for this crop, judged against the same standard as every other record in this file. GrowingHQ editorial synthesis — GrowingHQ Checked 2026-08-13	Earliness only. A tunnel is normally cropped in the ground, so soil-borne disease builds up under a rotation that never leaves cover. A greenhouse can sidestep it with pots or fresh growbags; a tunnel bed cannot. Potatoes and tomatoes share blight and eelworm, so planting both in the same tunnel bed compounds a problem the structure already has.

Growing it without soil

Nearly anything can be grown in a soilless system by somebody with enough equipment. The useful question is whether it is worth it, in which technique, and what goes wrong.

Not worth it

It can be made to grow, but a soilless system is the wrong tool — usually because of rooting volume, running cost, or a result no better than a pot of compost.

source

GrowingHQ editorial positionmoderate confidence

Potatoes form tubers along buried stem, which needs a deep medium that can be added to as the plant grows. Soilless systems can be built to do it and the result is an expensive way to grow one of the cheapest vegetables there is.

GrowingHQ editorial synthesis — GrowingHQ

Checked 2026-08-13

The economics decide this one rather than the horticulture.

Techniques that suit it

Ebb and flowA bed of inert medium floods and drains on a timer. The medium holds moisture between floods, which makes it far more tolerant of interruption than NFT.

Horticultural consensusDepends on conditionsmoderate confidence

Applies when: Deep medium beds only, and rarely worth the volume of medium involved.

No external citation — see the evidence type above.

Checked 2026-08-13

Root space: Very large. Tubers need depth and volume, and earthing up has no equivalent in a channel system.
pH band: 5.5–6.5

Where these figures come from

Root spaceHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

pH bandSourced guidancehigh confidence

Outside roughly this band, individual nutrients become unavailable even when they are present in the solution — which is why a crop can starve in a full reservoir.

Purdue Extension — Purdue University: Hydroponic solution management — pH

Checked 2026-08-13

No nutrient recipes here

GrowingHQ records pH bands, which are measurable properties of nutrient availability, and deliberately records no EC or PPM targets and no mixing instructions. Published targets vary by cultivar, growth stage, water source and technique, and the figures that apply to your system are on the product you bought.

Harvesting

Time from sowing or planting: 10–20 weeks

Sourced guidanceDepends on conditionshigh confidence

Applies when: About 10–13 weeks for first earlies from planting, up to 20 weeks for maincrops.

Royal Horticultural Society: Potatoes — timing

Checked 2026-08-13

When it is readyLift first earlies when the flowers open, or shortly after — that is the signal that tubers of eating size have formed. Maincrops are left until the foliage yellows and dies down, then given two more weeks in the ground to set their skins.
How to pick itLoosen with a fork well away from the stem, then lift by hand and search the soil — a surprising proportion of the crop stays behind otherwise.
Keeping itStore maincrops in the dark in paper or hessian sacks, cool but frost-free. Light turns them green, and any damaged tuber will rot and take its neighbours with it. Earlies do not store and are eaten within days.

Where the harvest guidance comes from

When it is readySourced guidancehigh confidence: Royal Horticultural Society: Potatoes — harvesting
Checked 2026-08-13
How to pick itHorticultural consensusmoderate confidence: No external citation — see the evidence type above.
Checked 2026-08-13
Keeping itSourced guidancehigh confidence: University of Maryland Extension — University of Maryland: Storing potatoes
Checked 2026-08-13

What goes wrong

Problem	How often	Notes
Physiological leaf roll	occasional source Horticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13
Late blight	common source Sourced guidancehigh confidence Royal Horticultural Society: Potato blight Checked 2026-08-13	The defining problem of maincrop potatoes in Britain. Earlies are usually lifted before it arrives.
Slugs and snails	common source Horticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13	Slug holes in tubers are commonest in maincrops left long in wet ground.
Magnesium deficiency	occasional source Horticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13

Start from what you can see

What to look for

Views that settle something a description cannot. Where the photograph has not been taken yet, the description of what it will show is here instead — which is the useful half of it either way.

Described view

A potato tuber with a distinct green area under the skin where it was exposed to light, alongside a sound tuber for comparison

Grown with, grown after, grown instead

Every relationship states its mechanism. A pairing nobody can explain is a pairing nobody has checked, and it does not go in.

Same rotation groupTomato
Both are Solanaceae hosting Phytophthora infestans and sharing soil-borne problems, so they belong to one rotation group and blight moves freely between them.
source
Sourced guidancehigh confidence
Royal Horticultural Society: Crop rotation
Checked 2026-08-13
Follows on fromCabbage
Potatoes are traditionally followed by brassicas in a rotation: the ground has been dug and cleared of weeds by the potato crop and by the lifting, which suits a crop planted out as transplants.
source
Horticultural consensusmoderate confidence
Royal Horticultural Society: Crop rotation
Checked 2026-08-13

Safety and edibility

Cats and dogsPainful or persistently unwell; veterinary advice worth taking

Listed as harmful to cats or dogs

Potato is listed as harmful if eaten. The green parts, the sprouts and any tuber that has greened in the light contain glycoalkaloids, chiefly solanine. Eating them causes drooling, vomiting, lethargy and, in quantity, neurological signs. A properly stored tuber is not the problem; a forgotten sprouting one in an accessible sack is.

source

Sourced guidancehigh confidence

ASPCA Animal Poison Control Center — toxic and non-toxic plant list — American Society for the Prevention of Cruelty to Animals: Solanum tuberosum — toxic plants list

Checked 2026-08-13

Affected parts: leaf, stem, fruit.

Toxicitychildrenpets
Green potato tubers, sprouts, and all the above-ground parts of the plant contain glycoalkaloids — chiefly solanine — which cause gastrointestinal illness and, in quantity, neurological symptoms. Greening is caused by light exposure and indicates that glycoalkaloids have increased with it.
source
Sourced guidancehigh confidence
- Royal Horticultural Society: Potatoes — green tubers
Checked 2026-08-13
Do not eat green tubers or sprouts: cut them out generously, and discard any tuber that is extensively green or tastes bitter. Store potatoes in the dark, and keep the fruits — small green tomato-like berries that appear after flowering — away from children.

Sources for this page

GrowingHQ editorial synthesis · Purdue Extension · Royal Horticultural Society · University of Maryland Extension · University of Minnesota Extension · USU Extension

Each figure on this page carries its own citation, under the “where these figures come from” note in its section. Record last reviewed 2026-08-13.

If something is wrong with it

Holes eaten in leaves — 2 causes GrowingHQ holds for potato
Leaves rolling or curling inwards — 2 causes GrowingHQ holds for potato

Something else? Work through it with the diagnostic tool.