Kailan (Brassica oleracea Alboglabra Group)
1 sources cited · Verified
The short answer
- Plant
- Early April to early July
- Site
- 6+ hours of sun, soil pH 6–8
- Biggest risk
- Damping-off
In the UK, kailans go in the ground early April to early July.
Kailans (Brassica oleracea Alboglabra Group) — annual or biennial grown as an annual.
Timing is the decision that matters most in the UK: there are 4 separate regional sowing windows, ranging from early April in Southern England to early April in Scotland.
Core growing advice on this page is checked against named horticultural and university-extension sources — see References.
Regional Planting Calendar
| Region | Sow |
|---|---|
| Southern England | early April to early July |
| Midlands | early April to early July |
| Northern England | early April to early July |
| Scotland | early April to early July |
Southern England - detail & sources
NC State gives "after the last frost in spring" as the planting rule rather than UK-specific dates; a spring-through-early-summer window is applied across all four sub-regions rather than inventing a north/south gradient the source does not support.
Midlands - detail & sources
NC State gives "after the last frost in spring" as the planting rule rather than UK-specific dates; a spring-through-early-summer window is applied across all four sub-regions rather than inventing a north/south gradient the source does not support.
Northern England - detail & sources
NC State gives "after the last frost in spring" as the planting rule rather than UK-specific dates; a spring-through-early-summer window is applied across all four sub-regions rather than inventing a north/south gradient the source does not support.
Scotland - detail & sources
NC State gives "after the last frost in spring" as the planting rule rather than UK-specific dates; a spring-through-early-summer window is applied across all four sub-regions rather than inventing a north/south gradient the source does not support.
Quick Facts
| Factor | Value |
|---|---|
| Soil pH | 6 - 8 |
| Sunlight | 6-6 hours direct sun |
| Soil texture | clay, loam, sand or high organic matter (NC State) |
| Drainage | good drainage |
| Lifecycle | annual or biennial grown as an annual |
| Edible parts | leaves, stems, flower buds |
At a Glance
Soil & Growing Conditions
Water: consistent moisture, good drainage (NC State)
Soil pH range
Span reflects genuine variation between the cited authorities, not a single agreed figure.
Growth Stages
| Stage | BBCH | Notes |
|---|---|---|
| Sowing | 0 | Direct sow or plant seedlings after the last spring frost; spacing 12in to 3ft depending on cultivar (NC State). |
| Leaf growth | 3 | Thick, glossy blue-green leaves develop; best growth between 64-82F, more heat-tolerant than other kales (NC State). |
| First harvest | 8 | Young leaves harvested 50-70 days after sowing (NC State). |
| Flower bud harvest | 6 | A second harvest is taken once flower buds appear; avoid delaying, as stems turn woody. Left unharvested, the flowers attract bees (NC State). |
Harvest & Storage
When to pick: Young leaves harvested 50-70 days after sowing, and again once flower buds appear. Avoid harvesting too late, as the stems become woody (NC State).
Diseases
Pests
Kailan, Leaf to Harvest
References
-
Height 1-2ft, width 1-1.5ft. Full sun (6+ hours) or partial shade (2-6 hours). Soil: clay, loam, sand or high organic matter; neutral pH 6.0-8.0; good drainage with consistent moisture. Best grown between 64-82F, tolerates summer heat better than other kales. Direct sown or planted as seedlings; in North Carolina, plant after the last frost in spring. Spacing 12in to 3ft depending on cultivar. Thick, glossy blue-green young leaves harvested in 50-70 days, and again once flower buds appear; avoid harvesting too late to prevent woody texture. PESTS: flea beetles, diamondback moth, borers, cabbage looper, aphids, grasshoppers, crickets. DISEASES: damping-off is the primary concern; good drainage helps keep this disease at bay. Suitable for coastal, piedmont and mountain regions of NC. Pesticide spraying not recommended for edible plants; flowers attract bees.
1 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 sow kailans in the UK?
In Southern England, from early April. In Scotland, wait until early April. Treat these as a guide rather than a fixed date — the governing rule is to sow only once frost risk has passed and temperatures are reliably warm enough.
When do I sow kailans?
Sow early April to early July.
What soil pH do kailans need?
A pH of about 6–8. 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 kailans?
Our data links 1 disease and 5 pests to this crop. See the sections above for each one and how to manage it.
Plan next season before the problems start
Most of the advice on this page comes down to timing and spacing — sowing at the right moment, rotating beds, and giving plants enough airflow. The UK Garden Planner lays your plot out month by month so those decisions are already made before the season starts.
Get the UK Garden Planner →Instant PDF download · Written for UK growing conditions
Last verified 2026-08-29
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.