How to grow lettuce
Overview
Lettuce is a fast-growing, cool-season leafy vegetable from the Asteraceae family, prized for its tender leaves and versatility in the kitchen. It thrives in mild conditions with consistent moisture and benefits from being sown in succession for a steady supply.
Varieties
- Cos — A classic upright romaine with crisp, sweet hearts, ideal for Australian gardens.
- Butterhead — Soft, buttery leaves that form loose heads; popular for its mild flavour and quick growth.
- Oakleaf — A loose-leaf variety with deeply lobed, tender leaves that are heat-tolerant and slow to bolt.
- Red Coral — A striking red loose-leaf with fine, frilly leaves that adds colour to salads.
Soil Preparation
Lettuce prefers a well-drained, loamy soil with a pH between 6.0 and 7.0. Enrich the bed with well-rotted compost or aged manure before planting to boost fertility and moisture retention.
Growing Guide
Sow lettuce seeds directly into well-drained, fertile soil in a position that receives morning sun and afternoon shade, especially in warmer months. Space plants 20–30 cm apart for loose-leaf types and 30–40 cm for heading varieties, with seeds sown just 3–5 mm deep. Keep the soil consistently moist but not waterlogged, and use a layer of mulch to retain moisture and keep roots cool. In hot weather, lettuce bolts quickly, so time your plantings for early spring or autumn in warmer zones.
Sowing
Sow lettuce seeds 3–5 mm deep in rows or scattered patches, and they will germinate in 7–14 days depending on temperature. For a continuous harvest, sow a new batch every 2–3 weeks and thin seedlings to 20–30 cm apart once they reach 5 cm tall.
Care
Feed lettuce every two weeks with a balanced liquid fertiliser during active growth to encourage lush leaves. Remove any yellowing or damaged leaves promptly to improve air circulation and prevent disease.
Companion Planting
Lettuce grows well with carrots, radishes, and spring onions, which share similar moisture and light needs. Avoid planting near brassicas like broccoli or cabbage, as they can compete for nutrients and attract similar pests.
Common Pests & Risks
Aphids and snails are common lettuce pests in Australian gardens; control them with a strong water spray or organic snail bait. Slugs can be managed by hand-picking at night or using copper tape barriers, while keeping the garden free of debris reduces hiding spots.
Harvesting
Harvest lettuce by picking outer leaves once they reach 10–15 cm long, leaving the centre to continue growing, or cut the whole head at the base when it feels firm. For the best flavour and texture, harvest in the cool of the morning before the sun wilts the leaves.
In the Kitchen
Use fresh lettuce leaves in salads, sandwiches, or as a garnish; they are best eaten soon after harvest for maximum crunch. Store unwashed leaves in a sealed bag in the fridge for up to a week, and wash just before use to prevent wilting.
Troubleshooting
Yellow leaves: overwatering or poor drainage; reduce watering and improve soil. Brown edges: tip burn from uneven moisture; water consistently and mulch. Bolting: heat stress; plant in cooler months or provide shade. Stunted growth: lack of nitrogen; feed with liquid fertiliser.