In the spring, begin setting out lettuce plants about a month before the last frost. Lettuce grows best within a temperature range from 45 to about 80 degrees. Hot weather makes it bitter; extreme cold freezes it. When well rooted, some Bibb types such as Buttercrunch will tolerate a surprising amount of frost.
So, in order to avoid premature bolting, I always direct sow lettuce in the garden very early in spring – as soon as the winter passes and soil thaws. This is usually somewhere in the first half of March.
Sow seeds in the ground 2 to 4 weeks before your last spring frost date or as soon as the ground can be worked. Or, to get a head start, start seeds indoors about 1 month before your last spring frost date. Harden off seedlings for 3 days to a week before setting outdoors.
Most lettuce is a cool weather crop, and you can plant it outdoors or start inside and transplant well before your last frost. Itll be liable to bolt in the summer, but you can plant another crop for autumn. Definitely succession plant, or sow new seeds every 2 weeks for a continuous harvest.
Results of Planting too Early
When you plant too soon when temperatures are too cool it can cause stunted plant growth, wilting, surface pitting, foliage necrosis, increase disease, and prevent healthy root development.
Based on the Clovis climate summary, your weather remains cool enough for lettuce from October through to April or May. Within this time, you should be able to grow more than one crop. Just be sure to grow it in fertile soil and keep the beds well irrigated during dry weather.
Lettuce should be transplanted when the plants are between 2-3 inches tall. You should harden off your lettuce plants 7-10 days before transplanting. Bring them outdoors for a few hours, increasing the length of time each day. Prepare your bed by loosening the soil and adding compost if available.
Here are some bad companion plants for lettuce: Cabbages and other brassicas: Cabbages, broccoli, brussels sprouts, cauliflower, kale, or kohlrabi can be bad companion plants for lettuce because they require similar nutrients from the soil, which can lead to competition and reduced yield.
For the beginner gardener, loose-leaf, baby-leaf, and mini-head lettuces, as they're most often labeled in seed catalogs, are the easiest varieties to start with — they're simpler, faster to grow, and milder than full-size head lettuce.
How to Grow: Lettuce is a cool-weather crop that thrives in the temperature range 60-65 degrees F, and if thoroughly hardened, most varieties survive temperatures as low as 20 degrees F. Cold-adapted varieties survive much lower temperatures. Seed germinates best at about 75 degrees F.
Generally March and April, when the soil begins to warm, are the best months to begin sowing many hardy annual vegetable seeds outdoors including broccoli, cabbage, chard, carrots, peas and parsnips.
Lettuce thrives and grows fastest in full sun, but it also grows well in light shade. In warmest regions, try to select a growing spot that offers afternoon shade. The ideal soil for growing lettuce is moist but well-drained.
Direct Sowing Lettuce
Don't bury them; this dusting is just to hold the seeds in place until germination and shouldn't be any thicker than the seeds themselves.
In mid- to late March, direct sow peas, spinach, fava beans, and arugula outdoors. Start peppers, tomatoes, eggplant, Swiss chard, and tomatillos indoors. In early to mid-April, direct sow early successions of radish, beet, carrot, lettuce, and parsnip outdoors.
Watering. When watering your lettuce, keep it light and consistent. For the first two weeks after planting your lettuce, you should water it lightly daily. After the first two weeks, you can start watering your lettuce less – twice a week or every four to five days depending on the temperature and shade level.
Lettuce is a cool-season vegetable that prefers sunny locations and fertile, well-drained soil. Plant seeds ¼-½ inch deep, 2-3 weeks before the last frost. Final spacing for head lettuce should be 8-12 inches apart in the row with rows 12-18 inches apart.
Romaine (Cos) Lettuce has tall heads of green leaves with crisp ribs down the leaf centers. Romaine is considered by some to be the best flavored of the lettuces. It's also fairly heat tolerant and one of the most nutritious.
Your container needs to be at least 6 inches deep, but I recommend going for one that's a foot deep and at least a foot wide so that you can grow several different types of lettuce in one container. When selecting your container, choose natural materials. My favorites are cedar, steel, and terra cotta clay.
Their seeds are small, so they don't need to be planted very deep, only about 1/4 inch. Since you'll be thinning the lettuce plants later, you don't need to worry about planting them too close. It's ideal to plant them close together so you can thin and enjoy baby lettuce as they grow!
If you're planning a garden that will provide you with salad stuffs, you're in luck, because lettuce and tomatoes are happy companions in the garden. When you plant lettuce near tomato plants, you will create a ground cover that will help keep the soil moist and cut down on weeds (and weeding).
Cucumbers and lettuce crave rich soil and plenty of water, so adding cucumbers as lettuce companion plants in a garden bed can streamline your gardening chores. Growing lettuce in the shade of vining cucumbers shields its leaves from bright sun and keeps lettuce from bolting early in summer.
Some gardeners find that germination is more successful by soaking lettuce seeds in cool water for between 16-24 hours, however that's not necessary. The key is to barely cover the seed after sowing, just a very fine layer of compost is sufficient as light is needed for germination.
Quick Guide to Growing Lettuce
Space lettuce plants 6 to 18 inches apart (depending on the variety) in an area that gets an abundance of sun and has fertile, well-drained soil with a pH between 6.0 and 7.0. Improve native soil by mixing in several inches of aged compost or other rich organic matter.
Lettuce is a good example of that. In the spring, when the soil is cool, it is best to use transplants. If planting in late August for a fall crop, feel free to direct seed. Lettuce seed will take two weeks to germinate in cold April soil but 3 to 4 days in the summer.