From early spring through until the frosts, lettuce will provide salad vegetables. To extend the season even further you can grow lettuce under a cloche or in a greenhouse.
For economy in growing a wide variety of lettuce, grow them from seed. If time and space make this unsuitable, you can buy seedling lettuce plants from your local plant nursery or even from your supermarket! If you look carefully, some suppliers are now offering mixed trays of seedlings, and this will allow you more variety.
Soil Lettuce needs a good, rich soil to do well. Grow in soil that was manured for a prior crop - it will be too rich if manured immediately before planting. If the soil pH is below 6 add some lime. Poor or compacted soil will not produce a good crop, and raised bed culture is ideal.
When planting in the garden plant in rows 15 to 20cm apart, in raised beds and containers you can plant in blocks.
Site A sunny or partially shaded site is best.
Growing from seed Lettuce seeds germinate better in cool soils and will become dormant in soil temperature of 25C and above. You can begin to sow seeds of cold tolerant varieties about four weeks before the last expected frosts. Sprinkle the seeds onto the top of the soil, either directly into the vegetable garden or in a starting tray, and cover lightly with soil. Dampen the soil and remember to keep the new seedlings and later the plants moist- lettuce needs moisture throughout the growing season.
As the seedlings develop you need to thin them. Starts when they are about 5 to 7cm tall, by thinning out the largest plants you have an instant salad. Continue to thin until there is 15 to 30 cm, depending on variety, between the plants.
Sow seeds every two to three weeks to provide for a succession of salad crops.
Seedlings Plant out about 15-30cm apart, depending on variety. Ensure the seedlings are kept moist and don't scorch. (An old gardeners trick is to lay wet newspapers alongside the plants to keep the soil moist. Watch out for slugs and snails, as they love moist conditions as much as your precious lettuce plants do!)
Harvest Pick lettuce at 45 to 50 days. Pick the outside leaves off the plant, it will continue to grow, or cut the pant 5cm above the base. Plants that are left after they have formed a firm heart will 'bolt' and become bitter.
Cultivation options Lettuce is an ideal plant to grow in containers, sow seeds of plant seedlings into a large pot, and place it in a sunny position. So many lettuces available now have frilly or coloured leaves- they make a great feature on the terrace. Watch carefully for signs of heat stress; container plants dry our much more quickly than those in the garden.
Lettuce grown in the garden are generally best grown in rows, 15 to 20 cm apart, depending on variety. In raised beds you can plant lettuces in blocks.
Bolting Bolting lettuce becomes tall and begins to bloom. The leaves are bitter and unpleasant to eat. Pull out the plants, and compost them. Dig over and prepare the ground for the next season's crop.
More Vegetable Gardening
From spring until the frosts, lettuce is essential for salads
Always remember to check the seed packet to confirm sowing time, depths and spacing.
A cloche will extend your season for salad vegetables
Ensure seedlings are kept moist
Pests and Diseases
The major pest is, of course, the infamous slug and snail community. Use beer traps or go out in the evening with a torch and remove the little beasties. You can use slug bait but as salad vegetables are not cooked before eating we strongly recommend organic methods of control. Rabbits are deterred by a physical barrier.
Downy mildew can affect plants in humid conditions. If your lettuce are being grown under cover, increase air circulation and reduce humidity. In humid weather your best chance is with planting resistant varieties.
Plant non-hearting varieties if you experience problems with rotting hearts
Non-hearting varieties - great for picking and in wet weather
Salads in Small Spaces If you want to enjoy fresh salad vegetables and have only a tiny space, then try growing your salads in a pot!
Plant the cut-an-come-again lettuces (e.g. lollo rosso and mesclun) lettuce varieties in a container. A few plants will provide enough leaves for a small salad, and you can harvest over a longer season with these lettuces.
If your hearting lettuce in the garden simply rots, these lettuce are the answer. And as for the slugs, a band of Vaseline around the pot below the lip of the container will foil these pests.
And to bring a bit of zest to your salad, add some chives and other herbs to the pot as well.