Now is a good time to sow Leek. Follow the sowing guide below.
Growing Calendar
This month: May
Log to journalStart seeds indoors this week
- •Fill tray with compost
- •Sow seeds evenly
- •Cover lightly with soil
- •Water gently
- •Place in warm light spot
Watch Out For
Leek moth tunnels through leaves from April
use fine mesh protection throughout the growing season for reliable prevention
Rust (orange pustules on leaves) in warm, humid conditions
improve airflow, avoid overhead watering and remove the worst-affected leaves
Allium leaf miner causes white streaking
cover with insect mesh in spring and autumn when adults are active
Grown Organically
Every method in this guide works with natural systems — no synthetic chemicals, no shortcuts.
Read our approachCommon Questions
About growing Leek in the UK
When do I sow leeks in the UK?
Sow leeks in February–March under glass, or April–May in a seedbed outdoors. Plant out from June to July when the seedlings are pencil-thick (about 20cm tall). Leeks are one of the most cold-hardy vegetables — they can stay in the ground all winter.
How do I get long white stems on leeks?
The white portion of a leek develops through blanching — excluding light. Use a dibber to make deep (15cm) planting holes, drop the seedling in, and water in without backfilling. As the plant grows, the stem naturally blanches in the darkness of the hole.
Why is my leek bolting?
Leeks bolt (run to seed) when exposed to a period of cold followed by warming — known as vernalisation. Bolted leeks develop a hard central core and are inedible. Harvest before this happens in spring, or choose bolt-resistant varieties.
Can leeks stay in the ground over winter?
Yes — leeks are fully frost-hardy and one of the most dependable winter crops. They can be left in the ground and harvested as needed throughout winter. Mulching the bed in very cold spells makes lifting easier.
Member guides
There's more to growing Leek than this guide covers.
Seasonal reminders, deeper guides, and the small adjustments that change a harvest.
