How to grow lettuce

How to grow lettuce

Sow seed on moist, well-prepared soil or compost in spring. Cover with a very thin layer of compost or vermiculite. Thin seedlings out when they're big enough to handle and keep the compost moist. protect from slugs and snails. Lettuce takes up to 10 weeks to grow – you can pick loose-leaf lettuce varieties from six weeks, and at 10 weeks for hearting types.

How to sow lettuce seed

If sowing in the ground, prepare the soil by digging in lots of well-rotted garden compost beforehand. This helps to prevent lettuces bolting or running to seed in hot or dry weather, especially in light soils.

Sow seed thinly along a moist, 1cm deep drill (trench), made by pressing a bamboo cane into the soil. Cover seeds thinly with soil or vermiculite (they germinate better with some light). Leave 30cm between rows.

If growing lettuce in pots, scatter seed sparingly over the surface of moist, peat-free seed compost and cover with a fine layer of compost or vermiculite.

When the seedlings are big enough to handle, thin them out to 10-20cm apart. (You can use the thinnings in a salad.) Water along the row to resettle the soil around the roots of remaining lettuce plants.

For a steady supply of lettuces, sow seed every 14 days from March through to September.

How to care for lettuce

Don’t let the soil get too dry, especially if the weather is hot, or the crop will bolt (run to seed). Mulch the area around your lettuces to seal moisture into the soil and feed your lettuce plants. Early- and late-season sowings are less inclined to bolt. Keep the area around the plants weed-free and protect young plants from slugs and snails.

Growing lettuce: problem solving

Slugs and snails can cause serious crop damage, so use copper-impregnated matting or mulch the soil with sharp grit or crushed seashells. Use wildlife-friendly slug pellets, made using Ferric phosphate, as a last resort. Red or purple lettuces seem to be less prone to attack.

Downy mildew fungus can ruin a crop. This is a particular problem in wet weather towards the end of the summer. Avoid splashing the leaves when watering lettuce plants and space them far enough apart to ensure there is good circulation of air.

Harvesting lettuce

Start picking baby loose-leaf lettuces at six weeks, at 10 weeks for hearting types. In hot weather you’ll notice a difference in the succulence of your lettuces according to the time of day they're picked. They’re best in the early morning, before the leaves dehydrate in the sun.

Preparing and using lettuce

Separate the leaves, then just give them a good wash in cold water and a shake dry.

Use them as the basis of a crisp salad or as a sandwich filler with cooked meats or cheese. If you have a glut, try using them to make a refreshing chilled lettuce soup.

Storing lettuce

Eat lettuces as soon as possible after harvesting, as the leaves will quickly go limp, especially during warm weather. If you can't eat all your harvest at once, then you can store lettuces for a few days in the salad drawer in the bottom of the fridge.

Lettuce varieties to try

There are two main types of lettuce: those that form a head/heart or loose-leaf types.

• 'Little Gem' – classic mini cos type, sweet and crunchy, very compact heart, dark green leaves
• 'Mascara' – frilled oak-leaf shaped leaves, deep red colour, slow to bolt
• 'Mortarella' – romaine type with attractive, rich green leaves
• 'Salad Bowl' (red and green) – non-hearting, crops all summer long, pick leaves as needed, slow to bolt
• 'Winter Gem' – mini cos type, suitable for growing over winter (sow August to January) if protected from frost, mildew resistant