How To Plant, Grow And Care For Lettuce

There are two kinds of lettuces: loose-leaf and head. Leaf lettuce is harvested by cutting the leaves off at the base of the plant, allowing the plant to regrow and produce multiple harvests. In contrast, head lettuce is harvested all at once when the head is fully grown, as it only produces one crop.

Common lettuce varieties often used for growth by yourself are:

Romaine

Romaine lettuce is one of the most popular lettuce. It is crispy and fresh and perfectly mild-mannered. You can buy romaine hearts, which are crunchier and stay longer in the fridge, or buy a whole head of romaine that comes with the larger, fluffier outer leaves.

The leaves are shaped like a boat, making it the perfect vessel for sauces and taco fillings. If you slice the leaves, it can be served on a salad.

Butterhead

Boston and bibb lettuces are the two most commonly sold varieties of butterhead. They are tender with a sweet, buttery, and fresh flavor, making them interchangeable in most recipes.

The butterhead lettuce has a cup-like shape, making it ideal for lettuce cups or wraps. They are also great in sandwiches, thanks to their tender lettuce leaves.

Crisphead

The most common variety of crisphead lettuce is Iceberg lettuce. It almost looks like a cabbage, but the texture and flavor are very different. Iceberg lettuce is mild, refreshing, and crunchy. It is a timeless burger topping.

Oak Leaf

The oak leaf is another common variety of leaf lettuce. They are shaped like oak leaves and can be either green or red. You can tear the leaves into any salad, but be careful not to squeeze or overwork them since they can bruise easily.

Little Gem

The Little Gem lettuce is a charming, smaller version of romaine with a sweeter and more delicate flavor. You can use it like romaine, but its smaller leaves make it perfect for salads, as they do not need to be chopped or torn. The leaves' distinctive shape also creates a natural "boat" that holds dressing and toppings beautifully.

Lettuce is a cool-weather crop and grows from February to April and September to November or even longer in areas with warm winters. Therefore, you should plant it when temperatures start hovering around 50 to 60 degrees Fahrenheit.

It is best to stop planting lettuce in early summer when the temperatures rise to avoid summer bolting. Instead, wait until late summer and allow them to mature in the cooler temperatures of autumn.

Newly transplanted lettuce seedlings need protection from frost for the first week or two after planting.

Where to plant lettuce

Apart from the timing, you should find a good spot to plant your lettuce. An ideal site offers at least six to eight hours of direct sun. You can grow lettuce in partial shade (three to four hours of sun), but plant looseleaf varieties that grow faster than heading types.

When planting lettuce seeds in late summer, it is essential to provide sufficient artificial shade to keep the soil cool and promote germination. As the days cool, you can remove the shade to allow the young lettuce plants to bask in the sunlight for healthy growth.

Once you have picked your spot, prepare your soil by incorporating a layer of compost or well-rotted manure. This will enrich the soil with vital nutrients and allow your lettuce plants to thrive.

How lettuce grows

You can directly sow seeds in the garden/container or transplant the seedlings you started indoors or purchased from a garden center.

Sowing

When seeding directly, plant approximately ten seeds per foot and space your rows 12 to 18 inches apart. Once the seedlings emerge, thin them out to a distance of 4 inches for leaf lettuce and 6 to 8 inches for Romaine and butterhead lettuce.

If you are confused, check the seed packet for specific spacing information. Be sure to plant the seeds at a shallow depth of ¼ to ½ inch, allowing them to receive enough light for germination.

Head lettuce is usually grown from seeds started indoors during warm weather for a fall garden. Transplant head lettuce in rows 12 to 18 inches apart with 10 to 12 inches between each plant.

Transplanting

If you wish to plant lettuce from transplants, start your plants indoors in the early spring. Then, transplant them outdoors two weeks after the last spring frost at 10- to 12-inch intervals in rows 15 to 18 inches apart. Allow similar spacing for pots or in mixed gardens.

Transplant seedlings after the temperatures have cooled and ensure you harden them off before taking them to the garden if you are planting lettuce during the summer. Most lettuce matures within 30 to 60 days, but depending on the variety, this may vary. You can check your seed packet for the maturation date. 

Lettuce grows quickly, but only if you maintain ideal growing conditions to ensure your lettuce crop is strong and healthy. If you follow the tips listed below, you will have a bountiful harvest.

Soil

Lettuce thrives in loamy, well-drained, nutrient-rich soil with neutral to slightly acidic soil of pH between 6.0 and 7.0. Therefore, check if the soil condition is suitable before you sow the lettuce seeds or transplant seedlings.

Also, it is recommended to till the soil and add compost or well-rotted manure about a week before planting your lettuce seeds to ensure a bountiful harvest. It will help create an optimal growing environment for your lettuce to thrive.

Sunlight

Lettuce does not grow well in the shade as they need full or partial sun to thrive. Full sun means at least six hours of direct sunlight on most days, and partial sun means four hours and six hours of sun daily.

However, if you are planting your lettuce when the temperatures are rising, they do need some shade to prevent overheat. However, too much shade can make the growth leggy and weak, so be careful.

If your lettuce is not receiving enough sunlight, the leaves cannot generate enough chlorophyll to keep their healthy green color, turning them pale and yellow. These leaves will eventually fall off, and the new growth is small and weak.

Water

Lettuces have a shallow root system and prefer smaller but frequent watering, especially early in the morning or late in the afternoon. Avoid excessive watering as it may cause diseases and root rot.

If you are unsure whether your plant needs water, check your plant's soil a few times a week, and water when the soil is dry down to an inch deep. For this, you might need to insert your finger in the soil.

For optimal growth, it is best to water regularly throughout the week whenever the top inch of soil feels dry to the touch. This approach is more effective than doing one deep watering per week. Dry soil can cause bolting, resulting in sun-scorched and bitter leaves. 

Temperature

Lettuce grows best in a temperature range between 45 and 70 degrees Fahrenheit roughly. They cannot stand extreme heat. Therefore, it is better to plant and grow lettuce in the spring. 

However, if you want to grow it in summer, some heat-tolerant varieties can make it through the summer. These varieties need extra care. They need to be planted in a bit more shade to avoid getting scorched by the afternoon sun or shaded using a cloth for extremely hot days if not, the leaves turn bitter. 

Humidity does not affect the plant’s growth as long as it receives enough moisture and airflow around the plant.

Fertilizer

Most vegetables require fertilizers such as manure, compost, and chemicals for growth. Manures and compost can enhance soil fertility by increasing its nutrient content. It should be mixed into the soil several weeks before planting to allow it to decompose.

If the soil is enriched, the only nutrient needed is nitrogen,  including urea, ammonium sulfate, calcium nitrate, and ammonium nitrate. You should follow label instructions to keep your plant growing well if you are using nitrogen.

You can also use fish emulsion, which is an ideal organic fertilizer. Work in the emulsion at half the recommended dosage every two weeks into the soil. You can use it as a foliar feed as well. 

Apart from caring for your lettuce, be on the lookout for some common pest and disease problems you might face when growing lettuce in a garden bed.

There are many environmentally friendly approaches to tackle them, and here are a few.

Pests

• Aphids are the biggest enemies of leaf vegetables. They feed on the plant juices and attack the stems, flowers, and leaves. You can plant garlic, leek, chives, and onion among your lettuce to help repel aphids. These pests do not like the strong scent of these vegetables.
• If you see holes in your leaves, they are probably caused by slugs. Slugs love to crunch the lettuce leaves. If you do not eliminate them on time, they might destroy the entire crop quickly.

Diseases

• White mold is a fungal disease that affects many plant species, including lettuce. Plants with white mold have stems that are discolored and wilted. To prevent this disease, you should not overwater your crop and ensure good airflow.
• Bottom rot of lettuce is common in wet soils and caused by fungus. Brown spots appear on the bottom leaves and soon spread to the entire stem or midrib.
• All types of lettuce are susceptible to this disease caused by Bremia lactucae. It causes light green to yellow angular spots on the upper surfaces of leaves. Damaged plants may require trimming at harvest, and you can use fungicide.

Some other measures you can take to prevent pests and disease.

• Use certified seeds and seedlings.
• Encourage natural pest enemies such as ladybugs.
• Use row covers and nets to protect lettuce plants from pest attacks.
• Avoid using too much fertilizer.
• Regular weeding and crop rotation can fight some diseases.

After six to eight weeks, your head variety lettuce is ready for harvesting. Leaf varieties only take a month. You do not have to harvest all the lettuce at once. You can harvest what you need and leave the rest for later. But do not wait until the leaves have matured for too long, as the plant will bolt and become bitter.

Harvesting Loose-Leaf Lettuce

• Wash your garden shears before harvesting the leaves to avoid potential cross-contamination.
• After that, cut mature lettuce leaves close to the stem.
• Work from the outside in. This allows the inner leaves to continue growing and maturing

Harvesting Head Lettuce

• Your lettuce head is ready for harvesting if it is fully mature and the center feels firm.
• Wash your lettuce knife with soap and water.
• Cut the lettuce at the base of its stem at the soil line.
• Chill immediately.

Storing Lettuce

After harvesting the lettuce, wash it thoroughly and eat it with your meal right away, but if you have excess harvest, you will want to store it correctly. 

If you are storing the lettuce leaves, do not wash them and follow these steps.

• You can keep your lettuce fresh for ten days in the fridge if you store it in a loose plastic bag.
• When you want to use it, run the lettuce in cold water for a few minutes and spin it in a salad spinner to remove excess water.
• If the lettuce leaves have wilted, submerge them in a bowl of cold water with ice cubes for about 15 minutes.