Indispensable lettuce

Lettuce is the most indispensable vegetable you can grow. After all, we eat its leaves 365 days a year, munching our way through bucket loads of salads and sandwich fillings. Their fast growth and small size makes lettuce the perfect crop to squeeze between other harvests, and if you’re tight on space, then they’re ideal for container living.
Not long ago ‘lettuce’ conjured up images of crunchy Icebergs and little more, but recently there’s been an explosion of seed packet choice. Now you can choose between dozens of different varieties, whether colourful crispy cos, soft smooth butterheads or mounds of frilly loose-leaved foliage. How you harvest them may vary, but their growing conditions are universally the same.

Growing Success
A lettuce’s dream is rich, moisture retentive soil that’s never too hot and never dries out. This means adding plenty of well-rotted organic matter, and in high summer choosing a slightly shady spot that won’t be blasted by the sun. June is still a great time to sow since the ground should be cool and moist enough for seedlings to thrive, just keep plants weed free and water regularly during dry spells.
Heat slows germination so, as June moves into July, it’s worth sowing seed later in the afternoon as temperatures start to fall for the night. Warm weather also makes plants less easy to transplant, so sow direct and thin to 20–25cm (9–10in)between plants or be very careful to keep transplants well watered. However you sow, make sure it’s little and often to prevent guilt-inducing gluts. When plants start to bolt (throw up a strong central spike) the leaves turn bitter and it’s time to rip them out and chuck them on the compost heap.
Slugs and snails are your greatest potential stumbling block. Sowing into modules, then planting out established seedlings that are better able to cope with the odd nibble can help. Nightly torch patrols are also valuable, along with the removal of nearby hiding places.

Cut-and-come-again
If you’re tight on space but have room for a container or trough, then try some cut-and-come-again cropping. Fill the container with multipurpose compost and either scatter the seeds broadcast, or sow in narrow drills, 10cm apart. Harvest the leaves once they reach 10-15cm using scissors or a sharp knife. Leave behind a 2.5cm (1in) stump from which the plants can re-grow, watering well after each cut.
You should get three or even four cuts, just remember plants are totally reliant on you for water. Look out for seed packet mixtures of different lettuce varieties, or make your own, adding other salad plants such as endives, rocket, spinach, mizuna and mibuna to the mix.

Lettuce Choice
You can split lettuces into approximately four groups (it’s never a precise art, with some varieties flitting between sections). Pick varieties from each group and you’ll guarantee a range of textures and flavours on your plate.
Cos (Romaine) are upright, sweet-hearted lettuces with crisp leaves. They’re better at coping with summer temperatures than other lettuces (they originate from Greece) and keep well in the fridge. You can pick individual outer leaves, or slice off the whole head with a sharp knife, leaving a stump to re-grow further foliage. Try diminutive ‘Little Gem’, chunky ‘Chartwell’ (T&M) or ‘Freckles’ (T&M) with looser red-splashed outer leaves.
Loose leaf lettuces don’t form a central heart, instead their outer leaves can be continually picked to ensure a plentiful harvest. Look out for ‘Salad Bowl Green’ or ‘Rouge Grenobloise’ (SOI) which has a crisper cos-like leaf.
Butterhead lettuces have silky smooth leaves and a melt-in-the-mouth texture. They need to be eaten as quickly as possible after picking and are typically harvested as an entire plant. Try ‘Marvel of the Four Seasons’ or colourful ‘Yugoslavian Red’ (T&M) with tinges of red, green and yellow.
Iceberg (Crisphead) have crunchy, tightly packed hearts that are picked whole and keep well in the fridge. ‘Webbs Wonderful’ is justifiably popular with its large, pale-leaf heart or try ‘Miluna’ (T&M) with good heat tolerance.

New Varieties:
‘Mini Green Improved’ Crunchy tennis-ball sized mini Icebergs (Thompson and Morgan).
‘Devil’s Tongue’ Large cos with loose heads of red/purple leaves (The Real Seed Catalogue).