With some planning, regular planting and correct variety selection it’s possible to grow lettuce all year round. With the protection of a greenhouse, cloche or fleece you can have lettuce growing into the coldest winters.
Most lettuce are ready to begin harvesting in 50 days with cut and come again or leaf lettuce varieties often ready far sooner than this. Succession sowing is essential.
When it comes to taste home grown lettuce is often sweeter, crunchier and and juicer. It’s also been proven that home grown lettuce is far better for your health with a far higher amount of vitamin A.
When & How To Sow Lettuces
Early in the season sowings should be done indoors in plug trays or small pots, sowings of winter varieties can begin as early as January if the plants can be protected from hard frosts. Main sowings will begin either indoors or directly outdoors from April and continue until late May. From late May to August plants can quickly go to seed so should be sown in a shady position. September is a good time to plant both quick growing varieties for harvesting before the main frosts but also larger winter hardy varieties that will give harvests throughout the winter months.
Seeds should be sown just less than half an inch (1cm) deep and covered with a very fine soil or compost.
Spacing for lettuce depends on the type grown, leaf lettuce should be about 4 inches (10cm) apart, cos and lose leaf varieties should be 8 inches (20cm) and large iceburgs should be 12 inches (30cm) apart. For winter planting increase these spacings by at least 2 inches (5cm) to allow for extra airflow and prevent any mould or rot.
Rows should be 12 inches (30cm) apart but for small plants or in good soil can be planted closer.
It’s important to keep sowing lettuce regularly to keep a supply going all season. Growing a few different varieties will ensure your harvest dates vary and cropping extended. In the Spring making new sowings every 2 weeks will keep the lettuce leaves coming while more slow growing winter varieties should be sown monthly.
Growing Lettuce Plants On
Lettuce are not really fussy about the soil they are grown in as long as it’s reasonably good. Being fast growing lettuce really like to get a lot of their food from liquid fertilisers, a general purpose feed or a good mix of liquid seaweed 3 weeks after transplanting and again after 5 weeks will give incredible growth.
If you expect to harvest within 7 days do not feed.
It’s important to keep lettuce plants well ventilated when they are in a greenhouse, cloche or under fleece. During warm days remove the plants protection for a few hours to allow fresh air to circulate around the plants.
Weeding of lettuce should really be done by hand once every two weeks. Small weeds should pull from the soil by hand easily and won’t damage the lettuces shallow roots.
Harvest your plants regularly.
Cut and come again lettuce should be picked from weekly. Once the plants begin to look tired another sowing should take over. Cut and come again lettuces grow quickly so multiple sowings a year can be made in the same ground.
It’s easy to tell when head lettuce are ready by squeezing the lettuce to see if the head is firm. Once the head is firm do not leave in the ground more than another week or two as they will quickly bolt and go to seed.
After harvesting if you quickly place the lettuce in a plastic bag in the fridge it will often last a week to ten days. Cut and come again types will usually wilt faster so should be eaten within 5 days. Long term storage of lettuce isn’t possible.