Sow in early to mid spring for spring crops, or in late summer to harvest in fall, and make successive plantings every few days to extend period of harvest.
Lettuce can be sown inside in trays, or directly out in the garden if the weather is right.
Planting lettuce indoors in a propagator
Prepare a propagator tray or small pot with a soil-less potting mix, ensuring that all big lumps, stones and sticks have been removed from the mix so it is as fine as possible. Sow a couple of seeds per compartment / pot to ensure that at least one seed germinates. Sprinkle a very fine cover of compost on the top, then water in well.
The seeds don’t need light to germinate, so you can place the containers in a warm dark place for a couple of days until you notice sprouting. Ensure that the soil remains moist but not waterlogged during the germination period. Move the container into an area with lots of light (if you don’t have natural light available, a grow light can be substituted at this stage). Remember if you are positioning the seedlings in sunlight, you should try to rotate them often to ensure they grow straight as they will otherwise try to bend towards the light.
When the seedlings are about 5cm / 2 inches tall, take a look at the seedlings in each compartment and choose the strongest one to keep. The others should be snipped back carefully, or if you are game you can try to repot these other seedlings into new separate containers (this can however be risky as you may lose all seedlings if you aren’t careful). Grow on until they are ready to go outside.
Sowing lettuce directly outside
Choose before you sow if you wish to grow the lettuce as whole heads or as cut-and-come-again leaves. If you wish to grow as whole heads, you could aim to keep a good distance between each plant and ensure that seedlings are thinned between each plant as they grow to ensure there is enough space for the lettuce to mature. They tend to grow best in rows. Before you sow, ensure that the soil is well worked and is completely free from stones and big lumps of soil, and begin thinning out when the seedlings are about 5 cm tall.
For salad leaves, you can sprinkle an area liberally with lettuce seed, then thin as you like.Try to aim for a seed spacing of at least 7.8 inches (20.0 cm) and sow at a depth of around 0.27 inches (0.7 cm). Soil temperature should be kept higher than 5°C / 41°F to ensure good germination.
By our calculations*, you should look at sowing Lettuce about 53 days before your last frost date .
Once your seedlings are about 5cm tall and all danger of frost has past, you can start to acclimatise your seedlings to the outside weather. To do this, put your seedlings outside for a period of time each day, increasing the time outdoors over about a week until you leave them outside for the entire day. Once your seedlings are “hardened off” they will be ready to plant. As per the sowing instructions, ensure your soil is well tilled, and set out in rows – ensure you leave enough space between plants for the variety you are growing. Water in well. Watch temperatures closely outside, if the temperature dips it can be wise to cover with fleece for the first week or so to ensure they survive as they establish themselves.Ensure that temperatures are mild (minimum night temperatures should be around 5°C / 41°F) and all chance of frost has passed before planting out, as Lettuce is a tender plant.
By our calculations*, you should look at planting out Lettuce about 10 days before your last frost date.
Harvesting whole head lettuce
Whole head lettuce should be harvested in the early morning, as they will be plump and full of water – which should help to retain their crispness. Try to cut the head about 3 cm from the soil level with a sharp knife, and a new head will sometimes develop. Try not to yank or pull the lettuce with your hands as it can disrupt nearby plants.
Harvesting loose leaf lettuce
As with whole head lettuce, early morning harvests are best for crispness as they have been in the cool night air for hours. Harvest only when the plant is large enough to be able to cope with a couple of leaves removed – this is normally when they are around 15cm / 6 inches in height, but depends on the variety. Try to pick only one or two leaves per plant to ensure that they keep producing leaves during the season. Use a sharp pair of scissors to cut each leaf, and try to take from the outside first.
Seed viability is three years.
These estimates for how long Lettuce takes to sprout, grow and harvest are from real observations from real gardeners, right around the world.
Average 7 days | Min 1 days | Max 21 days (1415)
Average 29 days | Min 2 days | Max 73 days (286)
Average 50 days | Min 1 days | Max 129 days (563)
Our when to plant Lettuce estimates are relative to your last frost date.
The name Lettuce (and the genus Lactuca) come from the Latin for “milk” – referring to the plant’s milky juice.
Lettuce , Lettuce crisphead, Lettuce "aunt mae's bibb", Stem lettuce
Lactuca sativa L.
Misspellings: Lettace, Lettice, Letice, Letace, Lactuga sativa, Latuca sativa, Lettuca sativa, Lactuca saliva