Brussels sprouts (Brassica oleracea Gemmifera Group)
9 sources cited · Verified
The short answer
- Plant out
- Late July to mid August
- Ready in
- 80–100 days
- Site
- 6+ hours of sun, soil pH 6.5–7
- Biggest risk
- Club root
In the UK, brussels sprouts planted out late July to mid August, and are ready to harvest 80–100 days after sowing.
Brussels sprouts (Brassica oleracea Gemmifera Group) — biennial (requires two growing seasons, but treated as an annual).
Core growing advice on this page is checked against named horticultural and university-extension sources — see References.
Soil & Growing Conditions
Quick Facts
| Factor | Value |
|---|---|
| Soil pH | 6.5 - 7 |
| Sunlight | 6-10 hours direct sun |
| Optimal growing temp | 12-20C |
| Minimum survivable temp | -5C |
| Time to harvest | 80-100 days |
| Soil texture | RHS: "fertile, well-drained, firm soil". Firmness matters because the plants are top-heavy. |
| Drainage | RHS: well-drained; a "sunny location". RHS advises raising the pH to at least 6.5 to deter club root; no upper bound is stated. |
| Lifecycle | biennial (requires two growing seasons, but treated as an annual) |
| Edible parts | sprouts, young leaves (sprout tops) |
At a Glance
Regional Planting Calendar
| Region | Plant out |
|---|---|
| Pacific Coastal Mild derived | late July to mid August |
| Central Continental derived | mid June to early July |
| Inland Valleys & Southern Lakes derived | late June to mid July |
| Atlantic Maritime derived | late June to mid July |
| Prairies & Short-Season Continental derived | late May to mid June |
| Far North & Alpine derived | early May to late May |
Rows marked derived are interpolated between regions our sources do state, because no source we consulted gives a figure for that region specifically. They are deliberately wider to reflect that uncertainty.
Pacific Coastal Mild - detail & sources
DERIVED from this region's own frost normal, not quoted for the region. Plant in early summer for a fall crop; 90-110 days to maturity, and frost improves flavour rather than ending the crop - the plant is not seriously damaged by temperatures below freezing. Count back from your first fall frost. Applied to a mean last frost of 18 March (NOAA NCEI 1991-2020 for the USA; Environment and Climate Change Canada normals for Canada), that gives 23 July to 12 August. Your own local frost date is what matters — a region spans a range, and this figure comes from one representative station within it.
Central Continental - detail & sources
DERIVED from this region's own frost normal, not quoted for the region. Plant in early summer for a fall crop; 90-110 days to maturity, and frost improves flavour rather than ending the crop - the plant is not seriously damaged by temperatures below freezing. Count back from your first fall frost. Applied to a mean last frost of 30 April (NOAA NCEI 1991-2020 for the USA; Environment and Climate Change Canada normals for Canada), that gives 19 June to 9 July. Your own local frost date is what matters — a region spans a range, and this figure comes from one representative station within it.
Inland Valleys & Southern Lakes - detail & sources
DERIVED from this region's own frost normal, not quoted for the region. Plant in early summer for a fall crop; 90-110 days to maturity, and frost improves flavour rather than ending the crop - the plant is not seriously damaged by temperatures below freezing. Count back from your first fall frost. Applied to a mean last frost of 30 April (NOAA NCEI 1991-2020 for the USA; Environment and Climate Change Canada normals for Canada), that gives 28 June to 18 July. Your own local frost date is what matters — a region spans a range, and this figure comes from one representative station within it.
Atlantic Maritime - detail & sources
DERIVED from this region's own frost normal, not quoted for the region. Plant in early summer for a fall crop; 90-110 days to maturity, and frost improves flavour rather than ending the crop - the plant is not seriously damaged by temperatures below freezing. Count back from your first fall frost. Applied to a mean last frost of 7 May (NOAA NCEI 1991-2020 for the USA; Environment and Climate Change Canada normals for Canada), that gives 30 June to 20 July. Your own local frost date is what matters — a region spans a range, and this figure comes from one representative station within it.
Prairies & Short-Season Continental - detail & sources
DERIVED from this region's own frost normal, not quoted for the region. Plant in early summer for a fall crop; 90-110 days to maturity, and frost improves flavour rather than ending the crop - the plant is not seriously damaged by temperatures below freezing. Count back from your first fall frost. Applied to a mean last frost of 21 May (NOAA NCEI 1991-2020 for the USA; Environment and Climate Change Canada normals for Canada), that gives 28 May to 17 June. Your own local frost date is what matters — a region spans a range, and this figure comes from one representative station within it.
Far North & Alpine - detail & sources
DERIVED from this region's own frost normal, not quoted for the region. Plant in early summer for a fall crop; 90-110 days to maturity, and frost improves flavour rather than ending the crop - the plant is not seriously damaged by temperatures below freezing. Count back from your first fall frost. Applied to a mean last frost of 5 June (NOAA NCEI 1991-2020 for the USA; Environment and Climate Change Canada normals for Canada), that gives 7 May to 27 May. Your own local frost date is what matters — a region spans a range, and this figure comes from one representative station within it.
Growth Stages
| Stage | BBCH | Notes |
|---|---|---|
| Germination & seedling | 0 | Sprouts are raised from seed sown about 1–2cm deep in spring, usually in a seedbed or modules rather than sown where they crop (RHS: sow March–April). Seed germinates in about a week in warm soil; grow plants on to sturdy young transplants of roughly 10–15cm with several true leaves before moving them. Harden off module-raised plants first. |
| Vegetative growth (transplanting & leafing) | 3 | Transplant from late spring into very firm, fertile soil, spacing plants about 60cm apart each way (RHS) — roughly 24–30in (Univ. of Maryland) — to give these big plants room. Firm the soil hard around each plant: loose ground produces loose, 'blown' sprouts. Water in well, keep weed-free, feed for strong leafy growth, and net against pigeons and cabbage white caterpillars. |
| Sprout formation (buttoning up the stem) | 4 | Small sprouts begin to form in the leaf axils and swell up the stem from the base towards the top. Keep plants firmly anchored and evenly watered; earth up the stems or stake plants on windy sites to stop them rocking, which loosens the sprouts. Removing a few yellowing lower leaves improves airflow. |
| Harvest (bottom-up over winter) | 8 | Start picking from the bottom of the stem upwards once the lowest sprouts are firm, tightly closed and about walnut-sized (RHS), usually from autumn onward. Flavour improves after the first frosts (Univ. of Maryland). Snap or cut sprouts a few at a time; a single stem crops over many weeks, and whole stems can also be cut for storage. |
Harvest & Storage
Diseases
Pests
Companion Planting
The Most Important Growing Tip: Firm Soil
Loose, soft soil is the number one reason Brussels sprouts fail in the UK. The plants need firm anchorage to produce tight, round sprouts rather than loose, leafy ones. Firm the soil thoroughly with your foot before planting, then plant firmly -- tug the plant gently afterwards, and if it comes out easily, plant it again more firmly. The RHS specifically highlights firm planting as essential to preventing loose, "blown" sprouts.
Recommended Varieties
- Peer Gynt — a classic early variety with tight, round sprouts from October; a compact, reliable choice across all UK regions.
- Trafalgar F1 — an AGM winner with heavy yields of firm, well-flavoured sprouts from November to January, and good disease resistance.
- Revenge F1 — a late-season variety harvesting January-March; very hardy, with excellent flavour after frost, useful for filling the "hungry gap".
- Evesham Special — a traditional tall variety producing large numbers of small, sweet sprouts from November to January.
Brussels Sprouts Through the Season
References
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Tier 1. Black rot shows yellow V-shaped lesions with the point of the V directed toward a vein, favoured by high temperature and humidity, surviving on debris up to two years when buried plus on wild mustard and contaminated seed; avoid cole crops where it occurred within two to three years and do not handle wet plants. Downy mildew is grey mould on the lower leaf surface with yellowing above. Alternaria leaf spot makes brown circular target spots with concentric rings between 60 and 90F, overwintering on residue, calling for three-year rotation. Pythium damping-off rots seedlings at the soil line.
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Tier 1. Diamondback moth is "the most serious insect pest of brassica crops in South Carolina", leaving a window-pane appearance where the upper leaf surface stays intact. Damage is quantified relative to each other: one cabbage looper does roughly the damage of 5 diamondback moth larvae, and imported cabbageworm about two-thirds of a looper. Cross-striped cabbageworm hatches in masses and can rapidly skeletonise a plant, dropping to pupate just under the soil surface. Cabbage webworm damages buds and growing points, causing lateral budding. Cabbage aphids are commoner in cool autumn weather. Flea beetles are most problematic on mustard and turnips, which lack the protective waxy coating.
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Tier 1. Transplants of 4-6 mature leaves take 6-7 weeks to raise; plant in early summer, early June to late July, for maturity in the fall; 12-18 in between plants with rows 2 ft apart; cultivars 90-110 days (Long Island Improved 90, Jade Cross 100, Diablo 110); grows best where temperatures do not exceed 70F and is not seriously damaged by temperatures below freezing; "Brussels sprouts taste better after they have been exposed to a few frosts. The frosts cause the sugars to become more concentrated"; remove the growing point when the lower sprouts begin to form, usually mid-to-late August, for uniform development; harvest at 1 in diameter, firm and compact, working from the bottom of the plant upward; stores 2-6 months at 32F and 95% relative humidity.
9 independent sources are cited for this crop. Where they disagree - soil pH is the clearest case - every figure is preserved rather than averaged into false precision.
Frequently Asked Questions
When should I plant brussels sprouts out in Canada?
In Far North & Alpine, from early May. In Pacific Coastal Mild, wait until late July. Treat these as a guide rather than a fixed date — the governing rule is to plant out only once frost risk has passed and temperatures are reliably warm enough.
How long do brussels sprouts take to grow?
Typically 80–100 days, depending on cultivar and growing conditions.
What soil pH do brussels sprouts need?
A pH of about 6.5–7. That span reflects genuine variation between the authorities we cite rather than a single agreed figure — the References section lists each source's exact range.
What problems affect brussels sprouts?
Our data links 5 diseases and 9 pests to this crop. See the sections above for each one and how to manage it.
Plan next season before the problems start
Short-season growing is arithmetic before it is technique: days to maturity against frost-free days decides what will finish at all. The Canada Garden Planner does that subtraction for your region before you sow.
Get the Canada Garden Planner →Instant PDF download · Written for Canadian growing conditions
Vegetable Growing Guides Canada
Last verified 2026-07-30
Where To Go From Here
Take this crop from reading into a written plan for your own beds.
Plan the next step
Use the printable SoilCommander planner for your region to turn this guide into sowing dates, bed layouts and weekly garden tasks.
