Lettuce is a relatively fast growing crop that can be tucked into corners and under tall plants like sweetcorn and brussels sprouts.
Lettuce is grown mainly for its refreshing, crunchy taste and to help provide body to salads. It contains reasonable amounts of vitamin A and potassium, and smaller amounts of a number of other nutrients.
Sow a few seeds every so often through the summer, perhaps every two to three weeks, to avoid having dozens of lettuces all maturing at the same time. There is a short interval between a mature lettuce and one that runs to seed, a process that turns the leaves thicker and less tasty.
- February – September
- Planting depth: 1.5 cm
- Planting spacing: 30 cm between plants, 30 cm between rows
- All year round
- Eat fresh, sow in succession to extend harvest period
Lettuces are grown for their leaves, and like many similar vegetables, the best results and the tastiest leaves are achieved by never letting the plants dry out. Big healthy lettuces are well watered and grown on a rich soil. If your soil is sandy, like at my local allotment, it is important to mix into the growing bed well rotted compost and to water often.
The most popular time to sow seeds is from when the whether warms up in the spring, and then in succession throughout the summer. To achieve an early spring crop, it is possible to sow hardy varieties in early autumn to overwinter.
The easiest way of growing lettuce is to sow direct into the soil. This avoids the time consuming task of transplanting. However, if you have a greenhouse or plastic growhouse, you will be able to sow earlier in the year into seed trays to achieve an earlier harvest.
If sowing direct in the soil, I first dig over the bed and add well rotten compost. I then mark out a row with canes and twine, before giving the line a really good dousing of water, and creating a shallow trench with a hand trowel.
I usually sow enough seed for half a row (about 1.5m) at a time. Young lettuce can get eaten by slugs and snails, so I am reasonable generous with my seed, sowing a seed every 2cm.
I then cover the freshly planted seeds with the already damp soil either side of the trench. This method avoids the need to water the freshly sown seed, that can wash the seed away, or too deep into the ground.
When the plants come up, thin the seedlings so that they are spaced about 6″ or 15cm apart.
In hot weather, lettuces are prone to bolt. This can be prevented by choosing varieties less prone to this behaviour and by watering frequently.
Loose leaf and butterhead lettuces are ideal to be harvested on a ‘cut and come again basis’. This is where you pick the outer leaves and leave sufficient inner leaves for the plant to recover, and provide you with further harvests.
I have found homegrown lettuces do not keep well compared to ones bought in supermarkets. A fresh vibrant plant seems to quickly turn into a flaccid heap.
A good solution for this is to prepare the lettuce for storing as soon as possible after cutting. The leaves should be separated and left to soak in water (this also gets rid of any unwanted slugs, snails, and other crawlies). After a few minutes, rinse off the leaves and leave to dry on paper towels or dishcloths. When the leaves are dry they can be bagged up and refrigerated, where they should remain good for a few days.
See lettuce varieties.