Lettuce

How to sow

Sow 1 cm. Use peat-free coco. Keep the surface just moist.

Germination 3–7 days in the crop record.

Growing

1. Sowing — Day 0. Scatter seeds on moist compost surface. Press gently. Do not cover — lettuce seeds need light to germinate.
2. Germination — Days 3–7. Keep moist. Tiny seedlings emerge within a week. Thin when crowded.
3. Seedling — Weeks 1–2. Thin to 5cm apart. Keep soil consistently moist.
4. Leaf growth — Weeks 2–3. Begin cut-and-come-again harvesting when leaves are 10cm.
5. First harvest — Week 4. Cut outer leaves at 2cm above soil. Inner leaves continue growing.
6. Peak production — Weeks 4–10. Harvest outer leaves every 5–7 days. Water consistently.
7. Bolt — Weeks 10–12. Remove and reseed. Bolting is accelerated by heat and long days.

Keep at or above 10°C where the crop record sets a floor.

Harvest

First cut around 4 weeks.

Cut outer leaves at 2cm above soil. Inner leaves continue growing.

Common mistakes

• Burying seeds — Lettuce seeds need light to germinate — covering them prevents emergence. Surface sow only. Press seeds onto moist compost. Do not cover.
• Too much heat — Lettuce prefers cool conditions. Above 25°C, germination drops and established plants bolt rapidly. Keep in a cool, bright spot. Avoid south-facing windowsills in summer.
• Harvesting the whole head — Cutting the entire plant kills it and ends production. Cut outer leaves only, leaving the centre growing. This extends harvest for weeks.
• Inconsistent watering — Lettuce is 95% water — irregular watering causes bitter flavour and wilting. Water every 2 days. Soil should be consistently moist, never dry.
• Not thinning seedlings — Crowded lettuce plants compete for light and produce leggy, weak growth. Thin to 5cm apart once true leaves appear. Use thinnings in salad.

In the kitchen

• Side salad — Tear leaves and dress with olive oil, lemon juice, salt, and pepper. Simple and immediate.
• Wraps — Use large outer leaves as wraps for mince, tofu, or rice. Replaces tortillas.
• Sandwich base — Layer whole leaves into sandwiches and burgers. Fresh, crisp, zero prep.
• Braised lettuce — Halve a dense head and braise in butter and stock for 15 minutes. Underrated cooked vegetable.
• Green smoothie — Blend tender inner leaves with fruit for a mild green base. Less bitter than spinach or kale.

Questions

Sources

1. Lettuce Seed Pack
2. Coco Soil treatise
3. HubWīk contents
4. Grower knowledge + RHS Growing Guides