Lettuce is quick and easy to grow, doesn’t take up much space in the garden, and offers delicious, mild-flavored leaves. Plus, it can be grown practically year-round with careful variety selection and season extenders like cold frames. I grow lettuce for both baby greens as well as full-sized heads in my raised bed garden and in containers on my deck. There are many types of lettuce to choose from and several ways to plant. In this article you’ll learn when and how to plant lettuce from seeds and seedlings and get tips on watering, succession planting, and harvesting.
Types of lettuce
There are many types of lettuce you can plant. I’m a big fan of looseleaf lettuce because it grows so quickly and you can harvest from each plant for weeks, but there are a lot of varieties available from seed catalogs and on seed racks:
- Looseleaf – Looseleaf lettuce is among the easiest to grow and is also super speedy, forming large loose heads in just five to six weeks.
- Oakleaf – I grow oakleaf lettuces as a leaf lettuce, harvesting often from the plants as they grow. If left to mature, they will eventually form full-sized heads. The leaves are lobed like oak leaves, and can be green or red, depending on the variety.
- Romaine – An essential ingredient in Caesar salad, romaine lettuce plants form tight, upright heads of crisp leaves.
- Butterhead – Butterhead lettuce, also known as Boston or Bibb, forms lovely loose heads of tender crisp leaves. There are heat-tolerant varieties of butterhead that can be grown in summer, as well as cold-tolerant varieties for winter harvesting.
- Iceberg – Iceberg, or crisphead lettuce has a reputation for being hard to grow but I’ve had no problem growing it in my raised beds.
- Summer crisp – Initially summer crisp, or Batavia type lettuces, look a lot like looseleaf varieties. But as they mature, they form beautiful rounded heads. There are many heat-tolerant varieties suited to summer growing.
Growing a lettuce garden
Lettuce is a cool weather crop and most varieties should be grown in spring and fall. The seeds germinate in temperatures as low as 40 degrees F (4 degrees C) but the ideal temperature range for lettuce germination and growth is between 60 and 65 degrees F (16 to 18 degrees C).
To grow great lettuce, find a site that offers at least six to eight hours of direct sun. It is possible to grow lettuce in partial shade (three to four hours of sun), but in low light I would suggest planting looseleaf varieties which grow faster than heading types. Once you’ve picked your spot, prepare the soil for planting by working in an inch or two of compost or aged manure. I also apply a slow release organic fertilizer at this time to provide nutrients for the plants.
If you don’t have garden space, lettuce also makes a fantastic container plant. They have shallow root systems and can be grown in this buckets, plastic pots, window boxes, fabric planters, baskets, or any container that is at least four to six inches deep and has drainage holes.
To get a jump start on the lettuce harvest, I cover my early spring garden beds with fabric or plastic covered mini tunnels. These capture solar energy and protect from cool temperatures and frost. Using a mini hoop tunnel lets me plant lettuce 3 to 4 weeks earlier in the season.
How to plant lettuce seeds
There are two ways to plant lettuce seeds:
- Direct sow seeds in the garden or containers.
- Transplant lettuce seedlings that were started indoors under grow lights or purchased from a garden centre.
Let’s learn more about these two techniques.
1) Direct sowing lettuce seeds
When direct seeding heading types of lettuce in rows, space the seeds two inches apart with rows twelve to eighteen inches apart, depending on the variety. Don’t sow the seeds deeply as they need light to germinate. I cover them with a scant 1/8 inch deep layer of soil. Once the seedlings are growing well, thin them ten to twelve inches apart, depending on the mature size of the plant. Check the seed packet for specific spacing information.
For a crop of baby lettuce, I sow the seeds in bands. You can make narrow bands that are just three to four inches across or wider bands to fit your space. I like to sow twelve to eighteen inch wide bands of baby lettuces in my raised beds, trying to space the seeds about two inches apart. You can grow a single variety this way or buy a packet of gourmet mixed lettuces.
2) Transplanting lettuce
When transplanting lettuce into my garden beds or containers, I typically plant in a grid pattern, spacing each seedling about ten inches apart. This is where you can have a bit of fun if you’re growing multicolored varieties like Salanova Mix. You can stagger the colors to create a checkerboard pattern. If transplanting in rows, space seedlings ten to twelve inches apart and rows twelve to eighteen inches apart, depending on the mature size of the variety. Again, refer to the seed packet for specific spacing instructions.
How to plant romaine lettuce
Romaine lettuce is one of the most popular types of lettuce and is very easy to grow. You can grow it as a baby crop and harvest the young leaves for weeks or you can allow the plants to mature to full-sized heads. For the best-tasting romaine lettuce give the plants consistent moisture, plenty of sunlight and cool temperatures. Because my garden is a slug haven, I find it helpful to start seeds for romaine lettuce indoors and move the seedlings out to my raised beds a week or two before the last expected spring frost. For full-sized heads of romaine lettuce, space them ten inches apart. Learn more about growing romaine lettuce.
Succession planting lettuce
Are you wondering how to plant lettuce so that you can have a very long season of harvest? The secret is succession planting and this is simply planting seeds at different times. I like to plant small amounts of lettuce seed every few weeks so we have enough for our family, but not so much that I can’t keep up with the harvest. I practice succession planting from early spring through early summer, and then start again in late summer when the nights are cooler.
If the weather is still hot and dry in late summer, set up a simple mini hoop tunnel overtop the garden bed. You can use a piece of shade cloth or row cover to create shade. This keeps the soil from drying out very quickly and helps boost germination. Learn more about how to use garden covers to maximize production in my book Growing Under Cover.
How far apart to plant lettuce
Once your lettuce seedlings are growing well, you can thin them so that each plant has enough room to mature into good-sized heads. You’ll find specific variety spacing listed on the seed packet, but generally a spacing of ten to twelve inches is best. If you want small-sized heads of baby lettuce, space the plants six to eight inches apart. This technique works well for romaine lettuce which then forms compact heads just six to eight inches tall.
How to grow a lettuce plant
Now that you know how to plant lettuce, it’s time to learn a few key growing techniques. The key to a high quality crop of tender, mild-tasting lettuce is consistent moisture. If lettuce plants are heat or drought stressed, the leaves turn bitter and the plants will bolt. Bolting is when the plants switch from leaf production to flower production and a flower stalk emerges. Read more about bolting here.
I live in a northern climate where spring often takes a few steps backwards and temperatures dip below freezing. Keep row covers handy to protect from frost or unexpected cold temperatures. They can be placed directly over the lettuce plants or floated above on hoops. You can also buy handy fleece tunnels online or at garden centres.
If your spring weather turns from warm to hot quicker than expected, keep lengths of shade cloth handy so that you can create a shady spot. It’s easy to make hoops from half inch PVC conduit, metal wire, or other materials. Lay a piece of 40% shadecloth on top of the hoops, securing it with clips. Shadecloth reduces the heat and light around your lettuce plants and can delay bolting by a week or two.
If you’ve worked organic matter and a slow-release organic fertilizer into the soil before planting, there’s no need to further fertilize fast-growing lettuce plants.
In my garden, the biggest threats to my lettuce plants are deer and slugs. If slugs are an issue in your garden, check out our guide on how to get rid of slugs. I find diatomaceous earth to be effective on slugs, but you must reapply after a rain. To keep deer and rabbits away from lettuce, use chicken wire cloches. Or, erect a mini hoop tunnel over your bed and cover with bird netting, chicken wire, or an insect barrier fabric.
Aphids are another common lettuce pest. These tiny, soft bodied insects suck the juices from the leaves, causing curling or distortion. Because lettuce grows so quickly, a modest infestation isn’t usually a big problem. I just give the leaves a quick wash before we make a salad. If there are a lot of aphids on your lettuce plants, you can spray with an organic soapy water spray to kill the insects and their eggs. This may require a few applications.
How to harvest lettuce plants
Once you’ve got a nice crop of lettuce coming along in your garden, how do you know when it’s time to harvest? There are several ways to enjoy your lettuce:
- Harvest as a baby green by picking individual young leaves or harvesting the entire immature plant.
- Selectively harvest outer leaves from looseleaf or heading varieties as the plants grow.
- Harvest the entire head by slicing it off about an inch above the soil.
For more information on growing greens, be sure to check out these awesome articles:
- How to start a new vegetable garden FAST!
- Grow your own salad garden
- Learn how to winter sow lettuce seeds
- Growing greens in a lettuce table
- 8 salad greens to grow that aren’t lettuce
- Red lettuce varieties to grow
Do you have any more questions about how to plant lettuce?