Sowing dates, transplanting windows, regional timing, and variety advice for a long leek season from summer through to spring.
Ready to start growing? Read our full How to Grow Leeks UK →
Sowing dates and growing advice verified against RHS guidance by the SoilCommander Growing Team.
Watch this short guide to growing leeks at home in the UK — covering sowing timing, transplanting with the dibber method, and harvesting through winter for the best results.
🌱 Did you know? Leeks are one of the few vegetables you can harvest fresh from the ground right through winter — they actually improve in flavour after a frost.
Key Facts at a Glance
UK Sowing & Planting Dates
| Method | When | Notes | Status |
|---|---|---|---|
| Sow indoors (modules/trays) | January – March | Sow thinly in trays or 2–3 seeds per module. Keep at 13–16°C. Germination in 14–21 days. | Recommended |
| Sow outdoors (seedbed) | March – April | Sow thinly in drills 1 cm deep, 15 cm apart. Thin to 5 cm. Transplant when pencil-thick. | Weather-dependent |
| Transplant outdoors | May – July | When seedlings are 15–20 cm tall and pencil-thick. Drop into dibber holes 15 cm deep, 15–23 cm apart. Water in; do not backfill. | Key step |
| Early varieties — harvest | August – November | Varieties like King Richard. Thinner shanks, milder flavour. Not fully frost-hardy. | Summer/Autumn |
| Maincrop varieties — harvest | November – April | Varieties like Musselburgh, Bandit. Thick shanks, strong flavour. Fully frost-hardy. | Winter/Spring |
Regional Timing Guide
🏴 Scotland & Northern England
Sow indoors from late January for the longest possible season. Transplant from late May to early June. Choose fully hardy maincrop varieties for reliable winter harvests.
🌧️ Midlands & Wales
Sow indoors from February. Transplant from late May. Both early and maincrop varieties perform well. Harvest from September through to March.
☀️ South & South-East England
Sow indoors from January or outdoors from March. Transplant from mid-May. Earliest harvest possible from August with early varieties.
🌊 South-West & Channel Islands
Mildest UK climate. Sow outdoors from early March. Transplant from May. Leeks can stand in the ground through to April without bolting in most years.
🏔️ Northern Ireland & Highlands
Treat as Scotland. Sow indoors from late January. Transplant in June. Stick to fully hardy maincrop varieties such as Musselburgh or Bandit.
Top Leek Varieties for UK Gardens
King Richard
A long, slender early variety ready from August. Mild flavour and attractive appearance. Not fully frost-hardy — harvest before hard frosts arrive. Ideal for the south.
Musselburgh
The classic British winter leek. Thick, sturdy shanks with excellent frost hardiness. Can stand in the ground through to March. Reliable across all UK regions.
Bandit
An AGM-winning late variety with dark blue-green foliage and outstanding frost resistance. Harvest from December through to April. Excellent for northern gardens.
Oarsman
A modern AGM variety with long, clean white shanks and good disease resistance. Mid-season harvest from October to January. Excellent uniformity for show or market.
Plan Your Entire Leek Season
The SoilCommander UK Vegetable Garden Planner includes month-by-month sowing and transplanting calendars for leeks and 40+ other crops.
Get the UK Garden PlannerTop 5 Timing Tips for Leeks
- 1Sow leeks early — January or February indoors — to give them the longest possible growing season.
- 2Transplant when seedlings are pencil-thick (about 15–20 cm tall). Too early produces weak plants; too late and seedlings become pot-bound.
- 3Use the dibber method: drop seedlings into 15 cm deep holes and water in without backfilling. The hole fills gradually, blanching the shank naturally.
- 4Choose your variety to match your harvest window. Early varieties (King Richard) ready from August but not frost-hardy. Maincrop varieties (Musselburgh, Bandit) stand through winter and into spring.
- 5Leeks left too long in spring will bolt. Harvest all remaining leeks by April before the central stem hardens.
Frequently Asked Questions
When is the best time to sow leeks in the UK?
The best time to sow leeks indoors is January to March, giving them a long growing season. Outdoor seedbed sowing works from March to April once the soil has warmed.
When should I transplant leek seedlings?
Transplant when they are 15–20 cm tall and about the thickness of a pencil — typically May to July. Use a dibber to make 15 cm deep holes and water in without backfilling.
How long do leeks take to grow from seed to harvest?
Leeks typically take 16–20 weeks from sowing to harvest. Early varieties sown in January can be ready from August. Maincrop varieties are usually ready from November through to April.
Can leeks survive frost in the UK?
Maincrop varieties like Musselburgh and Bandit are fully frost-hardy and can stand through the harshest UK winters. Early varieties like King Richard are less hardy and should be harvested before hard frosts in November or December.
Why are my leeks thin and spindly?
Usually caused by sowing too late, overcrowding in the seedbed, or transplanting too early. Sow in January or February, thin to 5 cm apart, and wait until pencil-thick before transplanting.
Related Guides
Plan The Timing Before You Sow
Use the planting window with a planner, seed-starting setup, and the full calendar so dates stay practical for your garden.
Plan the next step
Use the printable UK Vegetable Garden Planner to turn this guide into sowing dates, bed layouts, and weekly garden tasks.