With careful planning and a greenhouse or coldframe you should have no trouble growing salad crops all year long. Sow seeds every fortnight to ensure a continuous supply during the spring and summer, and sow seeds under cover in winter.
Many salad leaf varieties can be grown on a cut-and-come-again basis, where a few leaves are removed at a time and young leaves are left to grow to provide a continuous crop.
If you choose a wide selection of types and cultivars of lettuce and take advantage of growing them under cover, you can harvest lettuce leaves all year.
There are several types of lettuce: butterhead lettuces have an open habit, are quick to mature and will tolerate poor soils. Cos lettuces have an upright habit and an oblong head. Crisphead varieties yield large hearts with curled, crisp leaves and are less likely to bolt (run to seed). Loose-leaf lettuces do not produce a heart; instead you simply cut a few leaves at a time and leave the plant to continue growing.
Sowing Lettuce Seeds
Sow a short row of seeds every fortnight to ensure a continuous supply of lettuce. Sow seeds thinly 13mm deep in rows 30cm apart.
For a summer or autumn crop sow the seeds outdoors from March to August. You can also sow seeds in a heated propagator in February and plant them out in March under cloches.
For a winter crop sow seeds outdoors in August and cover young plants with cloches from late September. For an even later crop, sow seeds in a heated greenhouse in September and October and grow the plants on in the greenhouse.
During the hot summer months, soil temperatures may be too high for the seeds to germinate. Sow them in a shady area and water with cold water to keep temperatures down.
Thin seedlings of varieties with an open habit to 30cm, 23cm for compact cultivars and 15cm for loose-leaf types (if you are careful you can transplant the thinnings to generate a slightly later crop). Water regularly in dry conditions and protect young plants from birds with fleece or netting.
Harvesting your Lettuce
Lettuce is ready to harvest when it has developed a firm heart (except loose leaf varieties). Harvest them in the morning when they are at their most crisp and fresh.
Growing Salad Leaves
Salad leaves include baby leaves of different crops, such as beetroot and chard, and oriental salads to bring about a greater range of flavour. Most salad leaves can be grown as cut-and-come-again crops, and are easy to grow.
Varieties to try include: Chinese mustard, which has a mild, tangy flavour, corn salad, which can be sown all year round, mizuna, which can be used in salads and stir fries, pak choi, which can be harvested as a baby veg or left to form dense heads, and rocket, which brings a peppery flavour to salads.
All salad leaves have similar growing requirements and can bring exciting and varied colours and flavours to regular salads.