VegetablebrassicaSome care needed

Brussels sprouts

Brassica oleracea

A long-season crop occupying ground from spring until Christmas, and the one vegetable where firm planting is not a refinement but the entire technique. Sprouts on loose soil rock in autumn wind and produce open, blown buttons instead of tight ones. Frost genuinely does improve the flavour.

Position: Full sun
Water: moderate demand
Drainage: Moisture-retentive
Grows to: 75–100 cm × 50–60 cm
Hardiness: H5
Harvest: October to January
Difficulty: Some care needed

Described view

A brussels sprout plant standing in the ground in winter with sprouts buttoned tightly all the way up the stem, the lowest ones largest and ready and the top of the plant still a loose leafy rosette

August

Nothing to do

No sowing, planting, harvesting or pruning window falls in August.

Brussels sprouts’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	O	N	D
Sow under cover		February.	March.	April.
Plant out					May.	June.
Harvest	January.						October.	November.	December.

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 out
2–8 weeks after your last spring frost
source
Sourced guidancehigh confidence
- Royal Horticultural Society: Brussels sprouts — plant out
Checked 2026-08-13
Plant deeply and tread the soil down hard around each plant. If you can pull a leaf and the plant moves, it is not firm enough.

Conditions it needs

Light: Full sun
Frost: Very hardy
Hardiness rating: H5 (RHS)
Grows best at: 15–20 °C
Germinates at: 10–25 °C
Soil: Loam, Clay
Soil pH: 6.5–7.5
Drainage: Moisture-retentive
Water needs: moderate
Drought: moderate tolerance
Waterlogging: poor tolerance
Heat: moderate tolerance
Wind and exposure: poor tolerance

Where these figures come from

LightSourced guidancemoderate confidence

Royal Horticultural Society: Brussels sprouts — position

Checked 2026-08-13

FrostSourced guidancehigh confidence

Royal Horticultural Society: Brussels sprouts — hardiness

Checked 2026-08-13

Hardiness ratingSourced guidancemoderate confidence

Royal Horticultural Society: RHS hardiness ratings

Checked 2026-08-13

Grows best atSourced guidancemoderate confidence

Royal Horticultural Society: Brussels sprouts — temperature

Checked 2026-08-13

Germinates atSourced guidancemoderate confidence

Royal Horticultural Society: Seed germination temperatures

Checked 2026-08-13

SoilSourced guidancemoderate confidence

Royal Horticultural Society: Brussels sprouts — soil

Checked 2026-08-13

Soil pHSourced guidancemoderate confidence

Plant Finder — Missouri Botanical Garden: Brassica oleracea — culture

Checked 2026-08-13

DrainageSourced guidancemoderate confidence

Royal Horticultural Society: Brussels sprouts — soil

Checked 2026-08-13

Water needsHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

DroughtHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

WaterloggingHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

HeatHorticultural consensusmoderate confidence

No external citation — see the evidence type above.

Checked 2026-08-13

Wind and exposureHorticultural consensusmoderate confidence

Not because the plant is tender — it is very hardy — but because it is tall and top-heavy, and wind-rock is what ruins the crop.

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	Brussels sprouts 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	Grows well here	Brussels sprouts grows perfectly well on sandy without special measures, though it is not the soil it would choose.
Chalky and alkaline	Grows well here	Brussels sprouts grows perfectly well on chalky and alkaline without special measures, though it is not the soil it would choose.
Loam	Prefers this soil	Loam suits Brussels sprouts as it stands: The pH suits it: it wants 6.5 to 7.5, and this soil is in that range. Loam is among the soils it is recorded as suiting. The soil holds moisture, which saves a great deal of watering.
Silty	Grows well here	Brussels sprouts grows perfectly well on silty without special measures, though it is not the soil it would choose.
Peaty and acid	Works, with one condition	Brussels sprouts 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	Grows well here	Brussels sprouts grows perfectly well on shallow over rock without special measures, though it is not the soil it would choose.
Made ground and urban soil	Works, with one condition	Brussels sprouts will crop on made ground and urban soil, 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.

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

Space and spacing

Mature height: 75–100 cm
Mature spread: 50–60 cm
Rooting depth: 45 cm
Spacing: 60–75 cm apart

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: No external citation — see the evidence type above.
Checked 2026-08-13
SpacingSourced guidancemoderate confidence: Royal Horticultural Society: Brussels sprouts — spacing
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.

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 guidancemoderate confidence Royal Horticultural Society: Growing method suitability Checked 2026-08-13
Traditional dug bed	Well suited source Sourced guidancemoderate confidence Royal Horticultural Society: Growing method suitability Checked 2026-08-13
Raised bed	Well suited source Sourced guidancemoderate confidence Royal Horticultural Society: Growing method suitability Checked 2026-08-13
Polytunnel	Marginal source Sourced guidancemoderate confidence Agriculture and Horticulture Development Board — AHDB: Brassicas under protection Checked 2026-08-13
Hydroponics	Marginal source GrowingHQ editorial positionmoderate confidence A metre of plant standing for the better part of a year, and a crop that needs frost to be worth eating. A heated indoor system withholds the one thing that makes it good. GrowingHQ editorial synthesis — GrowingHQ Checked 2026-08-13
Greenhouse	Marginal source Sourced guidancemoderate confidence Agriculture and Horticulture Development Board — AHDB: Brassicas under protection Checked 2026-08-13
Container	Not suitable source Sourced guidancemoderate confidence Royal Horticultural Society: Growing method suitability Checked 2026-08-13	Too tall and too top-heavy for any practical container

Growing it

SupportStake tall plants on an exposed site, and earth up around the stem base in autumn. Wind-rock loosens the roots and the sprouts blow open — which is the commonest complaint about home-grown sprouts and is entirely preventable.
HarvestingPick from the bottom of the stem upwards as each sprout firms, and remove yellowing leaves as you go. The plant keeps producing up the stem for two or three months.
FeedingFeed in midsummer but stop by late August. Late nitrogen produces soft open sprouts rather than tight ones, which is the opposite of what is wanted.
WateringWater thoroughly while the plants are establishing and in dry summers. Sprouts that go short of water make loose open buttons rather than tight ones, and that is decided in late summer, long before anybody is looking at the plant.

Where this guidance comes from

SupportSourced guidancehigh confidence: Royal Horticultural Society: Brussels sprouts — care
Checked 2026-08-13
HarvestingSourced guidancehigh confidence: Royal Horticultural Society: Brussels sprouts — care
Checked 2026-08-13
FeedingSourced guidancehigh confidence: Royal Horticultural Society: Brussels sprouts — care
Checked 2026-08-13
WateringSourced guidancemoderate confidence: Royal Horticultural Society: Brussels sprouts — cultivation
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	Worse under cover 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	Height and season length, and a genuine requirement for cold — sprouts need frost to firm up and taste right, and a plant kept warm makes loose blown buttons.
Polytunnel	Worse under cover 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	Height and season length, with the same missing frost.

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

A metre of plant standing for the better part of a year, and a crop that needs frost to be worth eating. A heated indoor system withholds the one thing that makes it good.

GrowingHQ editorial synthesis — GrowingHQ

Checked 2026-08-13

The frost requirement is real rather than folklore: sugars accumulate in the buttons in response to cold.

Techniques that suit it

Drip-fed mediumSolution is dripped into an inert medium around each plant. The most forgiving technique and the one that suits large, long-season, heavy crops.

Horticultural consensusDepends on conditionsmoderate confidence

Applies when: Structurally possible and horticulturally pointless.

No external citation — see the evidence type above.

Checked 2026-08-13

Root space: Very large, with a real staking requirement.
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

When it is readyPick from the bottom upwards as each sprout becomes firm and walnut-sized. The plant keeps producing up the stem for weeks.
How to pick itPick from the bottom of the stem upwards, snapping or twisting each sprout off sideways so the stem is not torn, and take the yellowing lower leaves off as you go. Start with the largest sprouts at the base and work up over several weeks — the top of the stem goes on filling out. The leafy top can be cut and eaten once the sprouts below it are gathered, and whole stems keep better standing in the ground than picked and refrigerated.
Keeping itBest left on the plant and picked as needed. They keep far better outdoors than in a fridge.

Where the harvest guidance comes from

When it is readySourced guidancehigh confidence: Royal Horticultural Society: Brussels sprouts — harvesting
Checked 2026-08-13
How to pick itSourced guidancehigh confidence: Royal Horticultural Society: Brussels sprouts — harvesting
Checked 2026-08-13
Keeping itHorticultural consensusmoderate confidence: No external citation — see the evidence type above.
Checked 2026-08-13

Keep picking

Regular picking keeps this plant producing. Fruit or leaves left to mature signal it to slow down or stop.

What goes wrong

Problem	How often	Notes
Flea beetle	common source Horticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13
Cabbage root fly	common source Horticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13	Transplants are the vulnerable stage; a collar or mesh at planting is the control.
Clubroot	common source Horticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13
Cabbage white caterpillars	common source Horticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13
Aphids	common source Horticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13	Mealy cabbage aphid gets down inside the sprouts, where it is very hard to wash out.

Sources for this page

Agriculture and Horticulture Development Board · GrowingHQ editorial synthesis · Plant Finder · Royal Horticultural Society

Each figure on this page carries its own citation, under the “where these figures come from” note in its section. Record last reviewed 2026-08-14.

If something is wrong with it

Holes eaten in leaves — 3 causes GrowingHQ holds for brussels sprouts

Something else? Work through it with the diagnostic tool.