What Do You Do About Bitter Lettuce?

Planting and Growing Times

• Lettuce is a cool-season vegetable and best planted near the end of summer so it can grow during fall temperatures between 60 and 70 degrees Fahrenheit. Planting it while the weather is too warm will stunt its growth and make the leaves taste bitter, as the lettuce will bolt and begin to grow flowers and stalks too quickly. Crisp-head varieties are especially sensitive to heat, while leaf lettuce can withstand warm weather, but not for long periods of time.

Lack of Water

• If you don't give your lettuce plants enough water, the result is a bitter vegetable. Lettuce plants are extremely leafy and needs lots of moisture for the edible parts to maintain a sweet and crisp flavor. Your lettuce will taste bitter if the edges of the leaves start turning brown -- a sign that the plant needs more water. As long as the plant bed stays moist and is never completely dry to the touch, your lettuce should be adequately hydrated.

Soil Nutrition and Disease

• Without enough nutrients in the soil, your lettuce leaves will have a sour or bitter taste. Lettuce should grow quickly, so fertilize often -- but don't supply the soil with too much nitrogen, which gives an off-putting taste to lettuce. Instead, add wood ash to balance nitrogen levels and maintain the taste of your vegetables. Aster yellow phytoplasma, a disease that affects lettuce, can result in discolored leaves and bitterness. If the plant becomes misshapen and the inner leaves lose their green color, remove it from the plant bed. Take special care of the rest of your plants by watering and fortifying the soil until ripe.

Additional Planting and Storage Solutions

• To fool your lettuce into thinking it's still spring, mulch the leaves to keep the roots of the plant cool and maintain the fresh taste. You can also plant lettuce in the shade so sunlight won't speed up the growth process and make the leaves taste unpleasant. If you purchase bitter lettuce from a grocery store, wash the leaves thoroughly and refrigerate for a day or two before eating to lessen the unpleasant taste.