When you plant lettuce in the fall of the year it is extremely productive. Since the four basic types have the same basic growing requirements. Leaf lettuce is the easiest to grow and has the most varieties. This type will produce loose bunches instead of a solid head and it comes in various colors and textures and grow very well in cool and warm weather. When ready to harvest it is best to cut he leaves off at least an inch or two above the ground and it will reproduce giving you a second crop.
Ideal soil conditions for growing lettuce should have a PH of 6.0 or 7.0 and a good supply of nitrogen to get the best leaf production. In very warm weather when not harvested at the right time lettuce will turn bitter and go to seed very quickly. If you reside in a hot climate it is best to plant lettuce in partial shade or in an area where in will only get the morning sun or at least be in some sort of shade. Lettuce has shallow roots and it will need watering frequently because it becomes hard for it to compete with the root systems of weeds ( most weeds have deep roots) keeping it weeded is recommended also.
If you begin planting your lettuce using seeds is sure to plant them a good 5 inches apart. Again when harvesting, and to get the maximum flavor from your crop of ;lettuce is essential because when you allow mature lettuce to stand in your garden it turns "Bitter" and become tough.
Most farmers group lettuce into four different types and they are Crisphead, Leaf, Romaine and Butterhead.
Leaf Lettuce is a home gardener's favorite, because it matures quickly, varies in color from red to green and has smooth or curly leaves.
Butterhead is smaller in size but has a smooth buttery flavor.
Crisphead is the most common and found in your local grocery store, its leaves are thin and the color is light green and it grows densely packed together.
Romaine is the most flavorful ( in my opinion) of all the lettuce varieties, the plant itself is tall with lightly paced leaves that are dark green in color with the inner leaves has a little less color. This lettuce is very flavorful for salads. Romaine will bolt and turn bitter and to seed fast in very warm or hot weather. If your lettuce does turn bitter, crop off the smaller leaves wash well and store in the refrigerator for a few days and the taste does dissipate, but it is still best to harvest at the right time for the best flavor.
Eudora DeWynter offers tips on Fall Gardening of Lettuce on her blog at http://www.gardentoolguru.com