Everything you need to know about lettuce seeds

When should I plant lettuce seeds?
Lettuce is a cool-season crop, so the best time to plant depends on your climate.  In cooler regions, sow seeds outdoors as soon as the soil is workable in spring, about 2-3 weeks before the last expected frost.  For a continuous harvest, you can sow seeds every 2-3 weeks. In warmer climates, fall planting is ideal as lettuce bolts (becomes bitter) in hot weather.

Where should I plant lettuce?
Lettuce prefers full sun to partial shade.  It thrives in loose, well-drained soil that's rich in organic matter. Amend the soil with compost or well-rotted manure before planting.  Choose a location that receives at least 6 hours of sunlight daily, but in very hot areas, some afternoon shade can be beneficial.

How deep and far apart should I plant lettuce seeds?
Lettuce seeds are small, so sow them thinly about 1 cm deep.  Space the seeds or seedlings depending on the variety.  For loose-leaf lettuce, space plants 15-20 cm apart. For head lettuce, space them 25-30 cm apart to allow room for the heads to develop.

How often should I water lettuce?
Lettuce needs consistent moisture to prevent bolting and ensure crisp leaves. Water deeply whenever the top 2.5 cm of soil feels dry. Avoid overhead watering, as this can lead to fungal diseases.  Consistent watering is especially important during hot weather.

Do I need to fertilize lettuce?
Lettuce benefits from regular feeding. Apply a balanced fertilizer or side-dress with compost tea every few weeks. Avoid over-fertilizing, as this can lead to excessive leaf growth and make the lettuce more susceptible to pests and diseases.

How do I harvest lettuce?
Harvest lettuce when the leaves are young and tender. For loose-leaf varieties, you can harvest individual leaves as needed. For head lettuce, cut the entire head at the base when it feels firm.  Harvest in the cool morning for the best flavor.

What are some common problems with lettuce?
Lettuce can be susceptible to pests like aphids, slugs, and cutworms.  Diseases like powdery mildew and downy mildew can also be a problem, especially in humid conditions.  Provide good air circulation and avoid overhead watering to minimize disease risks.

How do I prevent lettuce from bolting?
Bolting, or premature flowering, occurs when lettuce is exposed to hot weather.  Choose heat-resistant varieties for warm climates.  Plant lettuce in a location that receives some afternoon shade during the hottest part of the day.  Consistent watering also helps prevent bolting.

Can I grow lettuce in containers?
Yes, lettuce grows well in containers. Choose a container that is at least 15-20 cm deep and has drainage holes. Use a good quality potting mix and place the container in a sunny location. Container-grown lettuce may need more frequent watering than lettuce grown in the ground.

What are the different types of lettuce?
There are four main types of lettuce: loose-leaf, romaine, crisphead, and butterhead. Loose-leaf lettuce has loose, open leaves and is easy to grow. Romaine lettuce has elongated leaves that form a loose head. Crisphead lettuce forms a tight, compact head. Butterhead lettuce has soft, buttery leaves and a slightly cupped shape.

How do I start lettuce seeds?
Lettuce seeds are small and should be sown shallowly—about 0.5 cm deep—either in seed trays or directly into the garden. Keep the soil evenly moist and at a temperature of around 15-20°C for the best germination. Seeds usually sprout within 7-10 days. Thin seedlings to 20-30 cm apart for larger varieties and 10-15 cm apart for loose-leaf types to prevent overcrowding.

What type of soil is best for growing lettuce?
Lettuce thrives in well-draining, fertile soil rich in organic matter, with a pH between 6.0 and 7.0. Adding compost before planting helps improve soil texture and provides essential nutrients. The soil should be loose and able to retain moisture without becoming waterlogged. Raised beds or container gardening can be good options for better soil control.

How much sunlight does lettuce need?
Lettuce grows best in full sun (6-8 hours of sunlight per day) but can tolerate partial shade, especially in hot climates. Too much direct sun in warm weather can cause lettuce to bolt, leading to bitter leaves. In hot regions, planting in a spot with afternoon shade or using shade cloth can extend the growing season. For early or late-season crops, full sun is ideal for fast growth.

How long does it take for lettuce to be ready to harvest?
Lettuce growth time depends on the variety. Loose-leaf types can be harvested in as little as 30 days, while head lettuces like romaine or iceberg take 60-80 days. You can pick outer leaves as needed for a continuous harvest or wait until the plant is fully mature. Harvesting in the morning keeps leaves crisp and fresh.

Can I grow lettuce in pots?
Yes, lettuce grows well in containers as long as they are at least 15-20 cm deep to accommodate the roots. Use a well-draining potting mix and ensure the container has drainage holes. Water more frequently than in garden soil, as pots dry out faster. Growing in pots also allows for easy movement to shaded areas during hot weather.

How do I prevent pests and diseases in lettuce?
Lettuce can be affected by aphids, slugs, and fungal diseases like mildew. Use row covers to protect young plants from pests and hand-pick slugs if necessary. Ensure good air circulation by spacing plants properly and avoid watering in the evening to reduce fungal issues. Crop rotation and removing plant debris help prevent recurring pest and disease problems.

Can I grow lettuce year-round?
Lettuce can be grown year-round with proper planning, though it prefers cooler temperatures. In hot summers, use heat-tolerant varieties and provide shade. In winter, grow lettuce in a greenhouse, cold frame, or indoors under grow lights. Successive plantings every 2-3 weeks ensure a continuous supply of fresh leaves throughout the year.