Lettuce is a great addition to any vegetable gardening. Not only is it healthy to eat, it takes up very little space, unlike pumpkins. But for an optimal crop a few simple guidelines are helpful.
To grow lettuce or any other vegetable, you need to have good soil. For lettuce, keep the nitrogen level high by using 30-10-10 NPK (nitrogen, phosphorus, potassium) fertilizer. This will provide the lettuce with the nutrition it needs to produce healthy leaves.
When planting lettuce seeds make sure they are planted 1/8-3/8 inch deep, separated by 6-12 inches (2-3.5 m) from the next plant. Romaine lettuce can be planted closer together but other crisp lettuce need more space. If you plant in rows, keep the rows separated by about 20 inches (6m).
The roots of lettuce do not grow very deep so it is important to weed often. Many other grasses and plants with deeper root growth can invade the lettuce.
Since lettuce lacks deep root growth it has to find moisture near the surface. Therefore it is important to keep the soil moist but not saturated. Try to keep the water off of the leaves and into the soil except for the occasional washing. Wet leaves especially during nighttime temperatures can lead to disease.
Like any other vegetable, lettuce plants have problems with diseases and pests. Many insects enjoy the lettuce leaves and the folds of the leaves also offer many places for fungi to grow.
Aphids, flea beetles and leafhoppers are common problems. Slugs are even more so. Cutworms are often seen. Washing with a high pressure hose can help temporarily, but be sure to do it early to give the leaves time to dry before nightfall. A good insecticide lightly applied will keep them under control for the long term.
One common fungal disease is anthracnose (Microdochium panattonianum). This fungus can stay alive in soil for many years. Bottom rot (Rhizoctonia solani) is another common fungus. This type of fungus usually occurs in soil that drains poorly. To combat these fungi, keep foliage dry and plant in good soil.
Another common problem with lettuce is bolting. Bolting is not a disease or pest but occurs when the plant goes to seed and the leaves stop growing. Bolting happens when the temperatures are consistently too high. To prevent this from happening, plant lettuce in shaded area or plant next to a shading crop such as corn.
With the proper preparation, planting technique and care you can have lettuce several times during a growing season.
