RHS Growing Guides
How to grow lettuce
Our detailed growing guide will help you with each step in successfully growing Lettuce.
Getting Started
Lettuces are quick and easy to grow, and come in many colours, flavours and textures – your salads need never be boring! Choose from large hearting lettuces to loose-leaf types and salad-leaf mixes for growing in even the smallest spaces.
Lettuce all year round
Lettuce lobjoits green cos
Lettuces are best sown regularly in small batches to provide continuous harvests but avoid gluts. This is particularly true with hearting lettuces, which should be cut as soon as they mature, before they flower (bolt), so you only need a few ready at the same time. Loose-leaf lettuces and salad-leaf mixes are even more simple and speedy to grow than hearting types and are harvested as a
Although lettuces are easy to grow, a few pests can cause problems. In particular, follow our tips on how to stop slugs and snails. Hot, dry weather can trigger premature flowering, which turns the leaves bitter. Keep lettuces well-watered and lightly shaded in summer, and re-sow regularly so you always have replacements on hand.
Home-grown lettuces beat shop-bought versions hands down for freshness, flavour and variety. So why keep forking out for plastic-wrapped lettuces that all too often end up wilting in the fridge? It makes much more sense to grow them yourself, to pick and eat fresh whenever you want them, at their tastiest, nutritious, vibrant best.
Month by Month
Jobs to do now
| J | F | M | A | M | J | J | A | S | O | N | D | |
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| Harvest |
Choosing
When buying lettuce seeds, there is a huge array of varieties to choose from, both tasty and decorative – from crisp and crunchy to succulent and juicy, vibrant green to deep red, frilly or smooth, and much more. One of the joys of growing your own is the wide diversity of leaves, far greater than you can ever buy in supermarkets. You can also choose from various hearting types or fast-growing loose-leaf and mixed salads too.
Hearting lettuces
Hearting lettuces, with their dense centre, generally take up to three months to reach harvesting size and you cut the whole head. These are best grown in the ground, as they take up more space, but can also work in large containers. There are three main types:
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Butterhead lettuces have an open shape and soft juicy leaves with a mild flavour. They are fairly quick to mature and tolerate poorer growing conditions. Eat them fresh as they don’t store well.
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Cos lettuces have an upright, oblong head and come in various sizes, with a crisp mid-rib.
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Crisphead lettuces produce large hearts of curled, crisp leaves with a mild flavour. They are more resistant to bolting (flowering prematurely) and store well in a fridge. This type includes the popular iceberg lettuces.
Loose-leaf lettuces
Loose-leaf lettuces and salad-leaf mixes produce less dense rosettes of foliage, ideal for picking individual leaves and for growing in small spaces and containers. They can be highly decorative, both in the garden and on the plate, with a range of leaf colours, shapes, textures and flavours. These are quicker to grow than hearting types and you can often pick your first leaves only a month after sowing, and continue for several weeks on a cut-and-come-again basis.
For easy, reliable and tasty varieties, look for those with an RHS Award of Garden Merit (AGM), which shows they performed well in trials – see our list of AGM fruit and veg.
For more veg-growing inspiration, visit the RHS gardens, which all grow a wide range of vegetables, including many lettuces and salad crops.
What and where to buy
Most gardening retailers sell a large choice of lettuce seeds. They are cheap, but don’t generally store well, so it’s best to buy fresh seeds each year, for more reliable germination.
Packs of plug plants are also available from many garden centres and online through spring and early summer, although the choice of varieties is usually limited.
Recommended Varieties
Lettuce — butterhead
Butterhead variety, good choice for summer cropping. Sow March to mid August.Excellent resistance to bolting and tolerance...
A small butterhead lettuce perfect for growing in small spaces. It matures early and has soft leaves with a mild taste.
Sowing
Lettuce seeds can be sown indoors or outdoors, in containers or in the ground, from spring through to autumn.
When to sow depends on when you want the harvest:
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For summer/autumn harvests: sow outdoors from late March to late July. For an even earlier crop, sow indoors in early February and plant out in early March under cloches or plastic tunnels
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For early winter harvests: sow outdoors in early August and cover plants with closed cloches from late September onwards. Alternatively, grow in a greenhouse border or container
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For spring harvests: sow a winter cultivar such as ‘Winter Density’ in September/October, either in an unheated greenhouse or in mild areas under cloches or in a cold frame.
When sowing in summer, bear in mind that high temperatures can prevent some cultivars from germinating. So in hot spells, sow in the evening, water with cold water and provide some shade to keep temperatures down. Hot sun can also cause plants to flower prematurely, so in the middle of summer it’s best to sow in sites that get some light shade, especially during the hottest part of the day.
Early and late sowings may need protection from the cold, using cloches, plastic tunnels or fleece.
Sowing indoors
Lettuces are mainly sown indoors when temperatures are too low outdoors or to keep seedlings protected from slugs and snails until they are larger and more robust.
Young indoor-sown lettuces can be moved outside in spring, after the last frost – see the planting section below. Alternatively young plants can be kept under cover during the colder months, in a greenhouse border or container.
Sowing outdoors
Lettuce little gem
Lettuce lolla rossa
Sow the small seeds thinly, 1cm (½in) deep, in rows 30cm (1ft) apart. Sow a short row every fortnight to provide non-stop harvests and avoid gluts.
For more tips, see our quick and easy container-sowing guides:
Lettuce plants, especially loose-leaf varieties, take up very little space, so are handy for filling any small gaps on the veg plot. They can also be sown between slower-growing crops, such as parsnips and sweetcorn, as they will be harvested before the main crop needs the space.
Thin out the seedlings as soon as the first true leaves appear and continue gradually until they are 15–30cm (6–12) apart, depending on the variety – check seed packets for recommended distances. The seedlings you remove can be added to salads. Thinning is particularly important with hearting types, as they may not form a firm head if overcrowded.
Be sure to protect your seedlings and young plants from slugs and snails. In early spring, you may also need to protect them from sparrows and cold temperatures by covering with fleece.
Planting
Lettuce salad bowl
Choose a warm, sunny site and prepare the ground by weeding thoroughly, then dig in about two buckets of garden compost per square metre/yard and firm gently. Rake the soil level, removing any large stones.
Alternatively, fill a large container, at least 30cm (1ft) wide and deep, with multi-purpose compost, then place in a warm, sunny spot.
In spring, plants will establish more quickly if covered with cloches or fleece. In hot weather, young transplants can quickly wilt, so water regularly and choose a lightly shaded spot, which should also deter bolting.
Take care to protect vulnerable young plants from slugs and snails. Early in the year, sparrows can be a problem too, as they find young lettuce plants irresistible. Protect with fleece, chicken wire or similar.
Plant Care
Watering
Water young seedlings and newly transplanted lettuces regularly, especially in warm weather. Continue watering frequently to keep the soil moist, aiming to prevent drying out.
Plants in containers are particularly vulnerable, as the compost can dry out rapidly, so check them regularly. They may need watering daily in summer.
The best time to water is early in the morning, to set the plants up well for the day. Try to avoid watering in the evening, as the dampness can attract slugs and snails overnight, as well as encouraging fungal diseases such as grey mould.
Mulching
Lay a thick layer of mulch, such as garden compost, around lettuce plants to help hold moisture in the soil and stop it drying out in hot weather.
Weeding
Keep seedlings and young lettuce plants free of weeds, so they don’t have to compete for water or sunlight, which can slow their growth.
Dense weeds can also offer hiding places for pests, such as snails, and reduce air circulation, which can encourage fungal diseases such as grey mould.
Flowering
When lettuces flower, the leaves turn bitter and inedible. They often start to flower (known as bolting) sooner in hot, dry weather, so take care to water regularly in summer.
It’s also best to grow them in light shade during the hotter months, where conditions are cooler and damper.
When growing in containers during the summer, move them out of midday sun if possible and keep them well watered, as the compost can dry out very quickly.
See our guide to deterring bolting.
Harvesting
Lettuce hollywood
Lettuce navara AGM
Lettuce rosedale AGM
Harvest in the morning if possible, when the leaves are fresh and juicy. In hot weather, put individual leaves straight into water to keep them from wilting.
Whole lettuces are ready to harvest when a firm heart has formed – cut through the stem leaving a stump about 2.5cm (1in) tall. This should re-sprout leaves to give you at least one, if not two, additional smaller harvests.
Loose-leaf varieties can be harvested as soon as the leaves are big enough to be worth eating, when about 10cm (4in) high. Harvest as a cut and come again crop – either snip a few leaves from each plant along the row, or let plants grow to maturity and snip all the top growth in one go, leaving a short stem that should re-sprout at least one more crop of foliage, as long as the weather isn’t too hot or dry.
Lettuces are best eaten fresh, but can be stored in the fridge in a plastic bag for a couple of days if necessary.
Problems
With their lush leafy growth, lettuces are attractive to several pests, including:
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Slugs and snails
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Aphids can feed on soft lettuce leaves, so check plants regularly and squash or wash off to prevent larger infestations
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Root aphids – can cause older plants to suddenly wilt and die. Grow new plants in fresh ground, covering with insect-proof mesh or fleece from June to August, or sow resistant varieties
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Sparrows may peck the young seedlings in early spring – cover crops with fleece if this is a problem
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Cutworms – these can eat the roots, causing plants wilt and die. To deter them, keep lettuces well-watered and clear of weeds, and cover crops with fleece
In cool, humid summers, grey mould may cause lettuce plants to decay. Remove any faded leaves promptly and space plants widely to ensure good air circulation. Harvest plants as soon as they reach maturity.
In hot, dry weather, lettuces can start flowering (bolting) before they reach maturity, which turns the leaves bitter. So keep them well watered, mulch the soil and sow in light shade in summer. Some varieties, including crisphead and cos types, are more resistant to bolting than others.
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