The soil must have a good organic matter content and should not be acidic. Incorporate compost to the site in autumn or early winter. Shortly before sowing rake to produce a fine tilth and apply a general fertilizer.
Thin seedlings once the first true leaves appear to avoid overcrowding. Water the day before. Continue to thin at intervals until the plants are 15-30cm (6-12in) apart depending on variety.
Put down slug pellets and protect seedlings from birds. Hoe regularly and keep moist unless growing under glass when the soil should be kept slightly more dry. Ventilate glass-grown lettuce regularly.
Always water in the morning or midday, watering in the evening will increase the chance of disease.
Lettuce is ready for harvesting once a firm head has formed, but can be cut for use at any point. If left longer the plant will begin to grow taller; a sign that it is preparing to bolt, it should be cut and used immediately.
Ideally uproot in the morning when there is dew on the leaves, then cut off the roots and add to the garden compost.