How to Grow Tree Collards UK
On this page
- Tree Collard (Brassica oleracea var. acephala)
- When to Plant Tree Collards in the UK
- Quick Facts
- At a Glance
- Soil & Growing Conditions
- Growth Stages
- Harvest & Storage
- Diseases
- Pests
- Tree Collard, Cutting to Woody Perennial
- Plan your Tree Collards planting
- Growing Tree Collard in another region
- References
- Frequently Asked Questions
In the UK, tree collards go in the ground early March to late May.
Timing is the decision that matters most in the UK: sowing early March, and that same window applies across all 4 regions covered here.
The short answer
- Plant
- Early March to late May
- Biggest risk
- Club root
Core growing advice on this page is checked against named horticultural sources — see References.
Tree Collard (Brassica oleracea var. acephala)
1 sources cited · Single source
When to Plant Tree Collards in the UK
When to plant tree collards in the UK: in Southern England, sow early March to late May. Find your area in the table below.
| Region | Sow |
|---|---|
| Southern England | early March to late May |
| Midlands | early March to late May |
| Northern England | early March to late May |
| Scotland | early March to late May |
Southern England - detail & sources
Gardening Know How gives spring as the propagation window (stem cuttings, not seed) with no UK-specific dates, so a spring window is applied across all four sub-regions rather than inventing a north/south gradient the source does not support.
Midlands - detail & sources
Gardening Know How gives spring as the propagation window (stem cuttings, not seed) with no UK-specific dates, so a spring window is applied across all four sub-regions rather than inventing a north/south gradient the source does not support.
Northern England - detail & sources
Gardening Know How gives spring as the propagation window (stem cuttings, not seed) with no UK-specific dates, so a spring window is applied across all four sub-regions rather than inventing a north/south gradient the source does not support.
Scotland - detail & sources
Gardening Know How gives spring as the propagation window (stem cuttings, not seed) with no UK-specific dates, so a spring 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 texture | well-draining, nutrient-rich; tolerates heavy clay (Gardening Know How) |
| Drainage | well-drained |
| Lifecycle | perennial or partial perennial, living several years |
| Edible parts | leaves |
At a Glance
Soil & Growing Conditions
Water: moderate, in rich fertile soil (Gardening Know How)
Growth Stages
| Stage | BBCH | Notes |
|---|---|---|
| Propagation | 0 | Take 12-inch stem cuttings in spring, plant vertically with a third above the soil; rooting takes about six weeks (Gardening Know How). |
| Establishment | 3 | Full sun preferred, though partial shade produces more tender leaves; well-draining, nutrient-rich soil, moderate water (Gardening Know How). |
| Perennial growth | 3 | Develops a tall, woody stem up to 12ft over multiple years; prune every few months to the first leaf axil to prevent it becoming tall, spindly and leggy (Gardening Know How). |
| Leaf harvest | 8 | Harvest young leaves for sweetness year-round in mild climates, never taking more than a third of the foliage at once (Gardening Know How). |
Harvest & Storage
When to pick: Harvest young leaves for their sweetness -- all foliage is edible, but older leaves need cooking. Never take more than a third of a plant's foliage at once. Leaves keep several days refrigerated (Gardening Know How).
Diseases
Pests
Tree Collard, Cutting to Woody Perennial
Plan your Tree Collards planting
When to sow and plant Tree Collards depends on your own frost dates. Check the UK vegetable planting calendar. To work out where it fits in your beds, sketch your plot in the free Garden Layout Planner.
Growing Tree Collard in another region
Sowing dates, frost timing and local advice differ by country. Use the guide for where you garden.
References
-
Hardiness USDA zones 5-11 (varies by variety); most varieties tolerate down to 30°F (-1°C), some down to 14°F (-10°C), some withstand triple-digit summer heat; thrives in high humidity but adapts to arid zones. Full sun preferred, but moderately shaded areas produce more tender, flavourful leaves. Soil: well-draining, nutrient-rich; tolerates heavy clay and acidic soils; lime application improves leaf taste. Height up to 12ft (3.66m), spread up to 5ft (1.5m) depending on variety. Planted in spring; propagated from stem cuttings, NOT seed -- 12-inch cuttings planted vertically with one third above soil, rooting in about six weeks. Perennial or partial perennial, living several years; up to 20 years in mild climates, several years with protection in colder regions. Moderate water needs in rich soil; little supplemental feeding needed in fertile soil, manure side-dressing for poor soils, annual calcium supplement (oyster or eggshell powder) recommended. Harvest young leaves for sweetness (all foliage edible), never taking more than a third of the foliage at once; young leaves eaten raw, older leaves cooked; keeps several days refrigerated. PESTS: cabbage looper larvae (hand-remove or apply Bacillus thuringiensis), mice and rabbits feeding on lower leaves. DISEASES: root rot possible in heavy soils with poor drainage. Left unpruned, becomes tall, spindly and leggy with few leaves -- prune every few months to the first leaf axil for bushier growth. Container-grown plants should be repotted yearly or biennially and staked.
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 tree collards in the UK?
In Southern England, from early March. In Scotland, wait until early March. 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 tree collards?
Sow early March to late May.
What problems affect tree collards?
Our data links 1 disease and 1 pest 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
How this guide is put together
The growing data on this page — sowing windows, pests, diseases, soil and site requirements — comes from named horticultural sources, listed in References below, checked against RHS and Met Office guidance. An automated pipeline assembles that verified data into the page you're reading: it selects which facts to lead with and builds the surrounding prose and layout. It does not invent a date, a source or a number — where a verified value for a field isn't available, the page leaves it out rather than guessing. A person reviews and publishes each page; nothing goes live unverified.
Related Problem Guides
Last verified 2026-08-29
Plan Tree Collards by month
The months this guide gives for sowing or planting, each with the full list of jobs for that month in the UK:
More from the same group (brassicas & mustards):
Growing advice for your part of the UK
Timing and conditions change a lot inside one country. These guides cover frost dates and growing seasons region by region.
Where To Go From Here
Take this crop from reading into a written plan for your own beds.
Keep going
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.