How to Grow Lettuce: Planting, Growing, Harvesting
Lettuce is a cool-season crop that can be planted in early spring or late summer. There are many different types of lettuce, so you can easily find one that grows well in your climate. Low-maintenance and fast-growing, lettuce can make a great addition to your garden beds, and can also be grown in pots indoors. And, like anything homegrown, it tastes much better than what you’d pick up at the store.
In this guide, we’ll teach you everything you need to know about how to plant and grow lettuce successfully.
The Most Common Lettuce Varieties
There are five main types of lettuce. Broadly speaking, most varieties are either head lettuce or leaf lettuce, although some are cultivated for their stalks. In the case of heading varieties, the lettuce leaves form a dense, compact head that looks very similar to cabbage. Leaf type lettuce doesn’t form a head; instead, the leaves are spread out in a loose bunch.
Let’s take a closer look at which lettuce varieties you can grow in your vegetable garden.
- Loose leaf lettuce or looseleaf lettuce is the most common type, and is also the fastest and easiest to grow.
- Cos or Romaine lettuce grows a large, upright head, with prominent leaf midribs. It’s also a great choice for warmer climates, as it tolerates heat better than other lettuce types.
- Crisphead lettuce or Iceberg lettuce is the classic salad variety and forms a round, cabbage-like head.
- Butterhead lettuce, also known as Boston or Bibb lettuce, forms a loose, leafy head, and it’s best known for its buttery flavor and mild crunch.
- Celtuce or stem lettuce is a variety grown for its thick seed stalk as well as leaves. Popular in Chinese cooking, it’s a rare find in shops and supermarkets, but definitely worth growing in your garden
Also check out our database with specific information about exciting lettuce varieties and cultivars you can grow in your garden!
When Is the Best Time to Plant Lettuce?
Lettuce is a cool season vegetable. Depending on where you live, you can either sow it in spring or grow it as a fall crop. The ideal temperature for growing lettuce is between 60°F and 70°F (15.5°C to 21°C).
Despite being a cool weather crop, lettuce is not frost-hardy. Always wait until the last frost has passed before sowing. Lettuce is also sensitive to hot weather, which can make it bolt and give its leaves an unpleasant, bitter flavor.
Planting lettuce from seeds can seem tricky, however, the fact that it prefers cooler climates can be used to your advantage. For example, if you have a greenhouse, you can even grow lettuce in winter. Alternatively, you can build a cold frame to extend your growing season into the colder months.
The lettuce planting time also depends on what varieties you’re planning to grow. For example, Romaine lettuce has a higher tolerance to heat and can be planted from mid-spring until the end of summer. If you want to grow Iceberg lettuce, pick a heat-resistant cultivar, such as Minetto or Summertime. Loose leaf lettuces, on the other hand, prefer growing in cool weather and cool soil, and are better suited for a spring or fall garden.
Where Should You Plant Lettuce?
For outdoor cultivation, plant your lettuce in a part of your garden that receives full sun, or at least six hours of sunlight per day. In hot climates, or if you’re growing lettuce in summer, pick a spot with partial shade, or make sure that the lettuce is sheltered from the intense afternoon sun.
How to Plant and Grow Lettuce
Lettuce makes a fantastic vegetable to grow in your garden. You can plant it directly in the soil, in raised beds, and even in your straw bale garden beds.
Let’s take a closer look at how to start your lettuce garden.
Prepare the Soil
Lettuce grows best in a loamy, well drained soil that’s rich in organic matter. Start by digging and turning the soil using a shovel, then incorporate plenty of compost and manure. This will provide the young plants with nutrients, but also act as a soil amendment. In gardens with heavy clay soil, compost will improve drainage, while in gardens with sandy soil, it will ensure that it doesn’t dry out too fast.
Planting Lettuce Seeds
Wait until the last frost has passed before you start sowing lettuce outdoors. As an alternative, you can try growing lettuce from seeds indoors and transplant them to your garden once the weather warms up.
Plant lettuce seeds according to the instructions on the seed packet. Lettuce seeds are small and need light to germinate, so don’t sow them too deep. Place the seeds on the soil surface, about 4 inches apart (10 cm). Use a thin layer of soil to cover them, then give them a good watering. If planting several rows, the space between the lettuce seeds should be 12 to 18 inches (30 to 46 cm).
Lettuce seeds germinate in about 7-10 days. Once the plants have at least two sets of true leaves, you can start thinning them until they’re 10 inches apart (25 cm) . You can use the lettuce seedlings that have been pulled out in salads, like baby greens.
This is a fast-growing plant, and leaf type lettuce is ready for picking in just over a month. For a continuous harvest, try planting in small batches every 10-14 days for the duration of the growing season, but stop sowing four or five weeks before the first fall frost.
Water and Mulch
Lettuce plants need moist soil to grow, and should be watered deeply and regularly. Lettuce seedlings, in particular, are very sensitive to drought. On average, you will need to water your plants twice a week. As the plants grow, you can also add a thin layer of mulch around them, to help preserve soil moisture.
Like all leafy greens, lettuce needs plenty of nitrogen to produce a lush, abundant harvest. If you’ve already incorporated plenty of compost in your soil before sowing, you don’t need to give your plants any fertilizer for the first month. Afterward, if you’re growing several crops or using the cut-and-come-again method to harvest, you can give your lettuce a slow-release organic fertilizer once every 6-8 weeks.
To ensure that your lettuce plants are growing well, remove weeds as soon as they appear. If allowed to develop, weeds will deprive your plants of valuable nutrients and can crowd out lettuce until it starts to bolt.
Ideally, you should grow lettuce in spring and fall. In summer, or if temperatures go above 70°F (21°C), you will need to protect your plants from the intense heat, which will lead to bolting. The easiest way is to build a tunnel out of shade cloth.
Lettuce Plant Common Problems and Solutions
Snails, slugs, aphids, and caterpillars are the most common lettuce pests. You can stay one step ahead of them by inspecting your plants daily. To get rid of caterpillars, simply pick them up by hand and drop them in a bucket of soapy water. For slugs and snails, you can set up a beer trap, use copper tape around your plants, or sprinkle some diatomaceous earth on top of the soil. As for aphids, spraying the lettuce with some soapy water should do the trick.
If your garden is likely to be visited by wild animals, such as deer or hares, the best way to keep your lettuce plants safe is to build an enclosure out of wire mesh. This should also keep birds out of your lettuce crop.
The leaf lettuce plant can be susceptible to diseases such as leaf spot, lettuce rot, white mold, downy mildew, or lettuce mosaic virus. The best way to prevent them is to grow disease-resistant varieties and make sure that your plants are receiving the right amount of light, water, and nutrients. Also, avoid planting lettuce in the same spot in your garden for more than two years in a row. Rotating crops helps to keep your soil healthy.
Companion Planting With Lettuce
Lettuce is a great companion plant for vegetables such as beets, carrots, parsnips, or radishes. You can also grow it next to onions, garlic, mint, or nasturtiums, which will help repel pests. Chervil, rosemary, and lavender are particularly effective at keeping slugs off your lettuce. Meanwhile, taller plants such as tomatoes, eggplants, or sweet corn can help provide valuable shade, especially during hotter days.
When and How to Harvest Lettuce Plants
The best thing about lettuce is that it doesn’t take long to grow. In fact, the sooner you harvest it, the better, otherwise it will start growing a flower stalk and turn bitter. You can harvest baby lettuce as early as three weeks after sowing. For other varieties, such as Iceberg lettuce, it’s best to wait at least six weeks.
You can use several methods to harvest lettuce plants. One of them is to simply cut the entire plant at the soil level. Or you can use the cut-and-come-again method and remove some of the mature outer leaves. By picking a few leaves at a time, you allow the inner leaves to develop, which is the best way to harvest lettuce so that it grows back.
Try to harvest leaf lettuce the same day you plan to use it. This vegetable can be stored in the fridge crisper drawer for a few days, but it will soon begin to wilt and lose its flavor and nutrients.
Alternative Lettuce Growing Methods
You can grow your own lettuce even if you don’t have a garden. Let’s take a look at some of the methods you can use.
How to Grow Lettuce Indoors
Growing lettuce indoors is relatively simple, and it allows you to grow and harvest lettuce year-round. The tricky part is finding a spot that receives enough sun. Lettuce seeds need light to germinate, and mature plants need at least 6 hours of sunlight per day to develop properly.
If you’re growing lettuce in containers, place your pots as close to the window as possible, so that they receive plenty of light. Morning sun is best, but avoid keeping your pots in a room that’s facing south, as the heat will lead to bolting. If your home is too dark or if you’re growing lettuce in winter, you can also use grow lights to give your plants a boost.
How to Grow Lettuce in Pots
Planting lettuce in pots is similar to growing it in your garden, but with fewer risks of pests and weeds. Start by picking your pots. The best containers for growing lettuce should be long and shallow. A plastic plant trough about 6 or 8 inches deep and with drainage holes at the bottom would be perfect.
Fill your container with a nutrient-rich, well-draining soil mix. Place each lettuce seed on top of the soil, about 4 inches apart. Keep the pot in a cool but sunny room, and water it regularly. After the seeds germinate, you can thin them out and care for them the same way you would if they were growing in your garden.
How to Grow Lettuce From a Stump
This is a fun growing technique if you don’t want to complicate yourself with seeding lettuce. And it works very well with store-bought lettuce too. Cut the leaves about an inch or two (2.5 – 5 cm) from the bottom. Then, pour about half an inch of water in a glass bowl or jar, and place the cut stem on top. Keep the bowl on a sunny windowsill, and change the water every day.
Your lettuce stump will start growing new leaves after a couple of days. Once it grows roots about 2 inches (5 cm) long, you can transplant it into a pot with soil, or keep growing it in water.
How to Grow Lettuce in Water
Growing lettuce in water is possible, but there’s one thing worth keeping in mind. Water doesn’t have nutrients, so you will need to give your plants a regular dose of liquid fertilizer to keep them growing. Otherwise, your lettuce will have a very bland taste. Also, make sure your plants receive plenty of light, whether natural or artificial.
A salad bowl staple, lettuce is the kind of plant anyone can grow. You can grow lettuce from seed or from stumps. You can find a spot for it on a kitchen windowsill or in your garden beds, in a pot or a hydroponic system. So if you’re looking for a versatile, low-maintenance vegetable, make sure to add it to your planting calendar.
Find more great vegetables to grow in your garden on our 28 Easy Vegetables page.