A Guide On Planting, Growing & Harvesting Lettuce

by Lettuce Be | Last Updated:

In the United States, lettuce is the most widely grown salad vegetable. As the basis of your salad bowl and your vegetable garden, lettuce can provide essential nutrition and provide a basis for a healthy diet. Lettuce fits into smaller spaces, it grows easily, and it loves cool weather. Use these lettuce growing tips to maintain a garden full of fresh, green lettuce.

how to grow lettuceLettuce: How to Grow It

Lettuce thrives when temperatures are between 60 degrees F and 70 degrees F. Lettuce is a quick- and easy-to-grow spring and fall crop. Many varieties can be harvested in as little as 30 days, and some are even harvested as microgreens earlier. Using a simple plan will provide you with a bountiful supply of salad greens no matter where your garden is, throughout multiple seasons.

When to Plant Lettuce

Lettuce loves cool weather. Start planting leaf lettuce in the spring as soon as the soil is ready for planting. Temperatures from 40 to 85 degrees F are needed to germinate lettuce depending on the variety. If lettuce is planted successively with a 10 to a 14-day interval between each planting, you will enjoy an extended harvest. For fall lettuce, plant the lettuce seeds one month before the hot, summer temperatures arrive, so they will begin to mature as soon as the air cools in autumn. The lettuce will usually have a bitter flavor and bolt if it is exposed to high temperatures.

Planting lettuce heads in a cold frame or indoors is ideal; however, transplanting them outside in the spring after the last frost date is preferred. You can get a head start on the growing season by growing lettuce from seedlings for transplant in early spring.

Where to Plant Lettuce

During the first spring frost and fall, lettuce grows best in a sunny spot. If you intend to grow lettuce during the summer or in warm planting zones, partial shade can provide protection. Sprouting lettuce in late summer requires a shady spot in order to cool the soil so that the seedlings can germinate. Once the weather cools, the shade can be removed in order to allow ample sunlight to reach the lettuce plants.

A soil that is loose and cool and that drains well will yield better lettuce growing conditions. Compost or manure might also be added to the planting area for better drainage and improved lettuce growing conditions. The addition of lime can help bring the pH to at least 6.0, which is crucial for optimal growth. If you have trouble growing lettuce, consider purchasing a soil test kit. Lettuce is sensitive to low pH.

Lettuce Planting Techniques

Planting lettuce seeds doesn’t take much work since lettuce seeds are often very small and only require planting of 1 to 2 inches deep. Rows of lettuce are traditionally used but consider alternating green and red lettuce rows for a whimsical look.

The distance between lettuce plants varies depending on the type of lettuce you’re planting. When directly sowing seeds into the soil, allow approximately 10 seeds per foot. Romaine and butterhead lettuce seedlings require 6 to 8 inches between each plant. Space your rows between 12 to 18 inches. Thin lettuce seedlings to 4 inches apart. Plant your seeds 1/4 to 1/2 inch deep. Microgreen seedlings or baby greens can be eaten or transplanted after being taken off the plant.

In most cases, head lettuce is planted from seed started inside when weather is warm, in rows that are 12 to 18 inches apart, with no more than 10 inches between each plant. Before planting each crop, you can incorporate organic matter such as rotting manure or well-decomposing compost.

A Lettuce’s Water Requirements

Root development is not required in lettuce. Instead, you should grow the lettuce’s individual leaves rather than its roots. Water lettuce lightly, frequently, and consistently. The goal is to simply keep the soil moist. It is important not to water too often; this causes root rot, diseases, and stunted growth.

Defending Against Common Lettuce Pests

An aphid infestation can easily destroy a lettuce patch. The leaves curl and wilt, losing all water and nutrients. These little white aphid pests spread disease and can also cause mold issues. They’re found on lettuce’s undersides. You can’t find a systemic insecticide to control aphids, so the best thing to do is to encourage natural predators, such as lady beetles, or to use neem or horticultural soap.

There are also insects that love lettuce, such as snails and caterpillars. Insecticides provide one option, but traps, organic baits, and handpicking provide organic solutions to these pests.

The lettuce might have a physiological condition called tipburn if it is beginning to curl and brown. Tipburn commonly occurs if lettuce leaves are not regularly watered. Trim the browned leaves and begin a regular watering schedule.

Harvesting Lettuce

It’s easy to harvest lettuce since it is one of the easiest vegetables to harvest. Typically, lettuce can be harvested between 30 to 70 days after planting. Lettuce harvest timing varies by variety and what it will be used for. Really, timing depends on personal preference. Lettuce harvested in the morning offers the best flavor, so harvest it when it reaches the desired size.

There are two ways to harvest lettuce. If the entire bundle is cut at ground level, then you can remove just a few outer leaves, or you can cut only the tops. If you harvest every other lettuce plant, you give it room to continue growing. Romaine, butterhead lettuce and head lettuce are all easily cut at ground level.

How to Grow Different Types of Lettuce

There are four varieties of lettuce grown in the United States: butterhead, romaine, head, and looseleaf lettuce. Although the growing and caring process for all varieties of lettuce is the same, each lettuce has distinct qualities in the garden.

Growing Head Lettuce

Crisphead lettuce, or head lettuce, is the lettuce type we call Iceberg. A favorite of salad lovers across the country, salad lovers often wonders how to grow Iceberg lettuce. You need to take extra care when growing Iceberg lettuce. You can plant head lettuce in your fall garden for the best results, as it cultivates sweeter lettuce by avoiding the hot summer months. Along with Iceberg, Ithaca, Great Lakes, and Crispivo are excellent cultivars of head lettuce.

Growing Romaine Lettuce

Most romaine lettuces take between 60 and 80 days to grow. They range in size from 10 inches tall to 20 inches tall and form bundles of thick, sweet lettuce leaves. In hot summers, romaine is able to grow without bolting, so an extended growing season works in its favor. Red romaine lettuce requires the same care and attention as green varieties. The interesting romaine cultivars are Green Towers, Red Eyes Cos, and Valley Heart.

Planting Green and Red Leaf Lettuce

Most leaf lettuce varieties are the easiest to grow. Although many people assume that growing red leaf lettuce is different, it is exactly the same as growing green lettuce. You can sow leaf lettuce thickly in a garden bed or container to harvest as young, tender lettuce, or you can grow lettuce in rows for nice bundles of loose-leaf lettuce. You can get two to three harvests from one planting of lettuce by trimming it to a few inches above the ground. Popular lettuce cultivars include Red Sails, Tango, and Slobolt.

Growing Butterhead Lettuce

Most butterhead lettuce cultivars produce tightly folded thick lettuce leaves with a delicate white color to the middle tender lettuce leaves. Its mild taste gives salads a sweet touch. Try it in your lettuce garden with Ermosa, Esmeralda, or Nancy.

Growing Lettuce: Frequently Asked Questions

How Long Does Lettuce Take to Grow?

Leaf lettuce matures relatively quickly. It reaches maturity in 30 days but can be harvested as soon as it reaches the desired size. Other lettuces need 6-8 weeks to reach full harvest size.

What’s the best time of year to grow lettuce?

Lettuce seeds germinate between 40 and 80 degrees F in low-temperature zones. Growing lettuce year-round is possible in these zones. The best growing days are between 60 and 70 degrees. Warmer zones can grow lettuce all through the winter if they plant it in the fall. There are several ways to extend the growing season in other regions, including row covers, cold frames, and greenhouses.

Can lettuce grow in hot weather?

Heat stresses lettuce. As a result, lettuce starts panicking, and the plant decides to produce large quantities of seeds. Plants develop seed stems, which divert nutrients toward seed production. This process, termed bolting, produces bitter lettuce.

For lettuce that doesn’t bolt, look for cultivars that can be grown in warmer temperatures. Slobolt is an example of a cultivar that can withstand bolting. In warm weather, it is beneficial to plant lettuce in shady areas, use a mulch to retain moisture in the soil, and sprinkle overhead irrigation to keep plants cool.