Leeks

Question 1

Explain site selection and soil requirements for leeks.

Answer 1

• Sunny, fertile, well-drained
• Don’t like fresh manure, low nitrogen reqs.
• pH 6.5 - 7.5
• Responds well to thorough cultivation
• Does not like heavy soil or soil that stays wet
• Often transplanted into beds vacated by early potatoes.

Question 2

Explain sowing of leeks in seedbed.

Answer 2

• Sow in a seedbed between late Feb and mid April
• Sow 13mm deep in rows 15cm apart
• Early sowings require protection as 7C needed for germination
• Thin seedlings to 2.5cm between.

Question 3

Explain transplanting of leeks from seedbed to bed.

Answer 3

• Transplant when 20cm tall (10 to 15 weeks)
• Trim leaves before transplanting to reduce transpiration
• Place in 15cm deep holes made with a dibber
• 23cm apart
• 38cm between rows
• Fill hole with water and this will backfill sufficiently.

Question 4

Explain the cultivation of leeks.

Answer 4

• Prepare site well ahead of time, incorp well-rotted manure/compost
• Keep weed free as they don’t like competing
• Earth up to get a long white cylinder.

Question 5

Explain harvesting of leeks.

Answer 5

Lift with a fork and place in a bucket of water.

Can be left in the ground until required, even in a harsh winter.

Question 6

Name a pest and a disease of leeks, including symptoms and control methods.

Answer 6

Leek Rust

• Fungal disease causing orange spots on leaves, disfiguring them
• Avoid overwatering; ensure good ventilation; grow resistant cultivars; Remove infected plants.

Leek Moth

• Small yellow-green caterpillar tunnels into leaves, secondary rotting
• Destroy infected plant; good hygiene; crop rotation; fleece.

Question 7

Name three leek cultivars.

Answer 7

• ‘Zermatt’
• ‘Neptune’
• ‘Krypton’