It's a shame that so many people automatically associate flavorless, boring old 'Iceberg' with the word “lettuce.” The world of lettuces is full of color, texture, and flavor. If you grow your own, you have that world at your fingertips. Or the tip of your trowel, as the case may be. Homegrown organic lettuce is a delight. You can harvest it whenever you have a craving for a cool, crisp salad, and the combinations of colors and flavors you can enjoy is limited only by your imagination.
Types of Lettuce
There are five main types of lettuce:
These are generally the most difficult types of lettuces to grow, mainly because they require a long, cool season to mature, and most of us simply don't have those conditions in our gardens. Crisphead varieties are ready to harvest approximately 95 days after sowing seed. In most of the U.S., to succeed in growing crispheads, you need to start the seed indoors in late winter.
- Cos (Romaine)
Romaine lettuces also require a fairly long cool season; 70 to 75 days until harvest. Gardeners in areas with very short cool seasons should start the seeds indoors. However, romaines have a distinct advantage over crispheads in that you can harvest the outer leaves of the head as it continues to grow in the garden.
The most well-known butterhead lettuce is 'Boston Bibb.' Butterheads are known for their very smooth (buttery) texture. They form loose heads, which mature 55 to 75 days after sowing. If you can't possibly wait that long, you can harvest the outer leaves of butterheads, and new leaves will grow from the middle of the rosette.
Batavians are probably the least well-known type of lettuce. They can be sown and harvested like looseleaf lettuces, but mature into crisp round heads fairly quickly, making them ideal for those gardeners who enjoy crisphead lettuces but have a short cool season. Batavians are ready to harvest (as heads) 55 to 60 days after sowing.
Looseleaf lettuces are the easiest to grow. They can easily be sown and harvested within a few weeks as tasty baby lettuces. Looseleaf lettuces are harvested by picking or cutting leaves from the plant. New leaves will form, and, as long as you sow fresh seed every couple of weeks, they will provide you with lettuce for plenty of salads.
Selecting a Site to Grow Lettuce
Lettuces are easy to grow, and even more so if you give them the conditions that make them thrive. Lettuces require at least 6 hours of sunlight per day. If you live in a very warm climate or have summers in which temperatures frequently reach the mid-eighties, try to give your lettuces a site that is protected from afternoon sun. This can hold off the bolting that is brought on by hot weather. If you can't protect them from the sun, consider installing a shade screen over them.
Lettuces also need good, loose, rich soil to grow well. Soil that has been amended well with compost or rotted manure is ideal. Soils with plenty of organic matter retain moisture better, which is very important in keeping these shallow-rooted veggies happy.
If you have poor soil in your garden and want to be assured of a decent lettuce crop, consider building a raised bed and filling it with a mixture of topsoil, manure, and compost, or plant your lettuce in a container.
Any pot or container that is at least four inches deep will do.
Lettuce can be started from seed, either indoors or directly into the garden. You can also purchase transplants at the nursery. If possible try to purchase organic seed or starts. There are several good catalogs that carry organic seeds, and many garden centers are starting to carry organically-grown plants.
To Start Seed Indoors:
Lettuce seeds should be started eight weeks before your last frost date. Sow them in sterile seed starting mix, or a mix you've concocted yourself. The soil should be kept cool, below 70 degrees Fahrenheit. Be sure to give them plenty of light, either by placing them in a sunny window or by starting them under lights. They can be planted out after your last frost date. Be sure to harden the plants off for three to four days before planting them into the garden.
To Plant Seed Outdoors:
Lettuce can be easily sown in the garden as long as your last frost date has passed and the soil is fairly cool. Lettuce usually won't germinate if the soil temperature is over 80 degrees. Simply sow the seed in rows or blocks, following the directions on the seed packet. You will probably have to thin the seedlings that emerge; you can use the thinnings in a salad. For a continual harvest, sow more seed every two weeks throughout the season.
To Plant Transplants:
If you purchase plants or have started your own indoors, you can plant them out after danger of frost has passed. To plant, simply dig a hole as deep as the rootball and twice as wide, place the plant into the hole with the crown of the plant at soil level and gently firm the soil around the rootball. Water them in well to settle the soil and eliminate air pockets. In general, head lettuces should be spaced about a foot apart, and looseleaf lettuces spaced six inches apart.
Growing Your Lettuce
The most important factor in succeeding with lettuce is meeting its moisture requirements. Because lettuce is shallow rooted and comprised mainly of water (nearly 95% water, actually) it simply will not grow if you let the soil dry out. The roots of lettuce reside in the top three to four inches of soil. If you stick your finger into the soil and the top inch is dry, you need to water.
This may require watering several times per week in hot, dry weather.
Fertilization is also important. If you are growing in soil that is full of organic matter, you may not need to fertilize. However, providing your lettuce with nitrogen-rich fertilizer will keep your plant growing well and producing regularly. Fish emulsion is an ideal organic fertilizer for lettuces. Apply the fish emulsion at half of the recommended dosage every two weeks. It is best to apply the diluted fish emulsion directly to the soil. You can use it as a foliar feed as well, but be sure to wash your lettuce really, really well before eating it.
As with anything in the garden, lettuces benefit from a good layer of mulch. Install a two to three inch layer of organic mulch, such as wood chips, straw, leaves, or grass clippings around the lettuce, being sure to leave a little space around the plant to prevent rot.
This layer of mulch will help retain moisture, keep the soil cool, reduce the amount of weeding you have to do, and keep the lettuce clean by preventing soil from splashing up on the leaves when you water.
Lettuce is bothered by very few pests and diseases. Slugs are its biggest enemy, and they can be thwarted by setting out a saucer of beer to trap them in, or by sprinkling diatomaceous earth or crushed eggshells around your plants.
These sharp substances cut the slugs' underbellies when they slide across it, and kills them.
Aphids can also be a problem. If they are, try knocking them off with a blast of water from the hose or try a homemade spray to get rid of them. Cutworms can also be a problem, and the best way to protect against them is to install a collar made of thick paper or cardboard around the base of any newly-planted lettuce seedlings.
If your pests are of the long-eared, four-footed variety, the best defense is to install a metal fence around the garden, or around the bed in which you are growing your lettuce. You can also try sprinkling cayenne pepper on the plants to deter the rabbits.
Lettuce is easy to grow, as long as you meet its basic requirements. And the benefits of doing so are well worth it: being able to harvest salads full of homegrown, tasty, organic lettuce mere minutes before mealtime is a luxury that you'll appreciate throughout the growing season.