Leaves & salads
Loose-leaf lettuce
Lactuca sativa var. crispa
Timings for your region
Suggested: Moderate · Explained in the glossary
Sow outdoorsmid March – early September
Harvestlate April – early November
Practical tip
Do not cut the whole head — pick the outer leaves and the same plant keeps giving for weeks.
Origin & history
All garden lettuce descends from wild lettuce (Lactuca serriola), a plant of the Mediterranean and Western Asia; the Egyptians were growing it more than 4,000 years ago and the Romans carried it north over the Alps. The pickable leaf lettuces are the older form — firm heads were only bred out from the 16th century onwards. The genus name Lactuca comes from the Latin lac, milk: snap a lettuce stem and white sap runs out.
Varieties
Oak leaf, Lollo Bionda and Lollo Rossa differ mainly in leaf shape and colour; red-leaved varieties grow a little more slowly but usually stand longer before they bolt. Batavia types form loose heads and cope best with heat. Ready-made cutting and baby-leaf mixes are sown thickly in a band and harvested with scissors. Loose-leaf lettuce is self-pollinating and almost always open-pollinated — saving your own seed works without any trouble.
Care
Thin to 15 cm even if it looks too generous: plants standing too close stay small and rot in the heart. Lettuce is shallow-rooted and needs even moisture — better a thorough soaking every second day than a daily splash, and always at the base rather than over the leaves. It is a light feeder and needs no nitrogen; a handful of mature compost when the bed is prepared covers the whole crop. Sow a short new row every two to three weeks and the supply never breaks off.
What can go wrong
Downy mildew is the commonest fungal attack: yellow patches bounded by the leaf veins, with a grey-white bloom underneath, encouraged by crowding and leaves that stay wet overnight. Space more widely, water at the base in the morning, take out affected leaves and choose varieties explicitly sold as mildew-tolerant. Slugs go for young seedlings first — plants already 10 cm across come through far better, and an evening round with a bucket does more than anything else in wet weeks. Brown, dried-out leaf margins are not a pathogen but the result of uneven watering.
Harvest, storage & kitchen
Pick early in the morning while the leaves are turgid — cut at midday, lettuce is already half wilted. Wash only just before eating and spin it thoroughly dry; stored wet it goes glassy within hours. Limp leaves usually recover in cold water. Wrapped in a damp cloth a portion keeps two or three days in the fridge; beyond that it is not worth keeping.
All timings are guide values for the given climate, not a guarantee. Weather, aspect and variety all have a say.