The Fertilizing Needs of a Lettuce Garden

Selecting Fertilizer

• A soil test is useful and reveals exactly what nutrients your soil is lacking. Your local cooperative extension office can provide information about how to go about having your soil tested, usually at little or no cost. In the absence of a soil test, use a balanced general-purpose fertilizer that contains equal amounts of nitrogen, phosphorus and potassium. A balanced fertilizer is labeled with numbers such as 10-10-10 or 20-20-20.

Planting Time

• Enriching soil with fertilizer before planting gives lettuce a boost and paves the way for a healthy crop. When the soil is properly cultivated to a depth of at least 8 to 10 inches, sprinkle about 1 pound of dry fertilizer on the surface, per 100 square feet of planting area, and then use a hoe or rake to work the fertilizer into the soil. Immediately after planting the seeds, sprinkle an equal amount of fertilizer in even bands about 4 inches to the side of each row.

First Side-Dressing

• Apply the first side-dressing of fertilizer soon after the lettuce plants emerge. To side-dress lettuce plants, sprinkle dry fertilizer along each side of the rows, about 4 inches from the plants. If you have several rows of lettuce, sprinkle the fertilizer midway between each row. Apply the fertilizer carefully and if any lands on the foliage, remove it immediately by brushing it off or spraying the lettuce with water. For side-dressing applications, use about 3 ounces of balanced fertilizer for every 10 feet of row.

Second Side-Dressing

• One application of fertilizer applied as a side-dressing after the lettuce plants emerge is usually enough to maintain high plant yields. However, if your lettuce plants display signs of weakness, such as a pale green color or stunted growth, a second side-dressing, equal to the first, is in order.

Compost

• Compost incorporated into the soil at planting time is beneficial because it feeds the plants while keeping the soil rich and healthy. However, compost alone isn't enough to sustain healthy growth and high yields throughout the season. If you use compost at planting time, skip the initial fertilization and don't add fertilizer until the lettuce plants emerge. At that time, side dress as directed above, but reduce the amount of fertilizer by half.