Lettuces are simple to grow and available in a variety of colours, flavours, and textures. There are mainly two varieties: hearting lettuces, which have a dense centre, and loose-leaf lettuces, which have open leaves and no heart. Several combinations of salad greens can also be grown and harvested when still fresh and fragile.
There is a great variety to pick from when buying seeds.
Hearting lettuces are divided into three categories:
Butterhead lettuces are quick to mature, have an open shape, and can withstand less favourable growing conditions.
Cos types have an oblong, upright head.
Crisphead varieties are more resilient to bolting and produce huge hearts of curled, crisp leaves (going to seed prematurely). Iceberg lettuces are included in this group.
While they grow less densely, loose-leaf lettuces and salad leaf mixtures are perfect for growing in confined spaces and containers, plucking individual leaves, and producing smaller amounts of produce. A variety of colours, flavours, and leaf shapes are available.
Sowing
It is best to grow lettuces in areas where there is full sun available and moisture-retentive soil. If planning to sow early or late in the year use a cloche, plastic tunnels or horticultural fleece to protect against against the colder weather. If there is limited space, you can grow lettuces in containers or growing bags, but they will need to be watered regularly.
When it comes to sowing, place the seeds in rows about 13mm deep. If you plan on having a continuous harvest, sow a new row every fortnight.
When to Sow | When to Harvest |
|---|---|
Late March to late July | In summer/autumn |
Early August, then cover from late September | In early winter |
From September to October in a greenhouse or cold frame | In spring |
Growing
As soon as the first genuine leaves develop, thin the seedlings and continue until the plants are spaced 30 cm (1 foot) apart. You can include the seedlings you thin in salads.
Ideally, water first thing in the morning when the soil is dry.
While the lettuce plants are young in the spring, sparrows can be an issue since they are attracted to the plants. Use fleece, chicken wire, or anything similar to protect. Defend plants against snails and slugs as well.
Harvesting
If you routinely sow lettuce using suitable seasonal kinds, you can harvest it from late spring through the winter.
Harvest whole lettuces when a firm heart has formed - cut through the stalk at the base.
As soon as the leaves are large enough to be worth eating, loose-leaf types can be collected. You can either cut all the leaves from one plant or just a few outer leaves from each plant.