Lettuce

Mar / Apr, May / Jun, Jul / Aug
May / Jun, Jul / Aug, Sep / Oct
Indoors | Outdoors

Why Grow It

It’s increasingly difficult to find good quality, fresh lettuce in the supermarkets. Lettuce is easy to grow and with a little planning, you can eat it fresh for 9 months of the year.

There are four main types of lettuce. The first three (butterhead, cos and crisphead) form hearts at their centre and are usually grown as proper heads of lettuce. They take longer to mature. The fourth type (loose-leaf/’cut-and-come-again’) doesn’t form a heart and is therefore generally grown as a ‘cut-and-come-again’ crop, where leaves are cut as required. We cover the fourth type in our Salad Leaves section.

  • Lettuce will do well in any reasonable soil, as long as it’s moisture retentive – add well-rotted manure or compost the previous winter.
  • When growing heads of lettuce, sow one seed per module in a module tray.
  • Lettuce needs light to germinate, so don’t cover the seeds with compost.
  • Lettuce will not germinate in temperatures above 25°C, so if the weather is warm you may need to move the trays into a cool shed for a few days until they germinate.
  • Seedlings are ready to plant out when they have 4 or 5 leaves.
  • Harden off well before transplanting.
  • Use fleece or cloches to protect early sowings from frost.
  • Lettuce is a great space filler – you can pop it anywhere you have some space. Spacing is about 20-30cm depending on the type.
  • Plant the seedlings well down in the soil with the cotyledons (seed leaves) just above the soil level.
  • Keep the soil around the plants weed free and water copiously in dry weather – this will help prevent them bolting.
  • Cos, butterhead and crisphead varieties of lettuce need to be left longer than ‘cut-and-come-again’ salad leaves in order to develop their hearts.
  • Harvest lettuce leaves early in the day and they will keep far longer. This is because later in the day the moisture has evaporated from the leaves and so it wilts more quickly.
  • Sylvesta (butterhead)
  • Little Gem (cos)
  • Saladin (crisphead)
  • Slugs eat young leaves and get into the hearts of lettuces.
  • Aphids (black or greenfly) can be a problem.
  • Leatherjackets (the larvae of daddy longlegs) eat through the stems of newly planted lettuce.
  • Sow successionally – just 10 seeds or so at a time, every couple of weeks.
  • Try growing summer lettuce in partial shade – they don’t like hot weather.