Broadcasting. When a large area needs to be fertilized – for instance, a new lawn – a recommended rate of fertilizer is spread over the growing area and incorporated into the soil. Broadcast spreaders are usually used for this purpose. Water in the fertilizer after application.
Banding. When fertilizers are broadcast and worked into the soil, much of the phosphorus is locked up and is not immediately available to the plant. Banding is one way to make phosphorous available as the first roots develop. Narrow bands of fertilizer are applied in furrows 2 to 3 inches from the garden seeds and 1 to 2 inches deeper than the seeds or plants (applying the fertilizer band too close to the seeds will burn the roots of the seedlings). To apply fertilizer by banding, run a string between 2 stakes where the row of seeds is to be planted. With a corner of a hoe or a trowel, dig a furrow parallel with the string 3 inches deep and 3 inches to one side of the string. Spread 1/2 the suggested rate of fertilizer in the furrow and cover it with soil. Repeat the banding technique on the other side of the string. Then sow your seeds underneath the string. For widely spaced plants, such as tomatoes, create bands 6 inches long for each plant or in a circle around the plant, 4 inches from the base of the plant. Do not permit fertilizer to contact seeds or the base of the plant.
Side-Dressing. During the growing season, fertilizer may need to be applied for heavy feeders which require a lot of nitrogen. Scatter the fertilizer near the plant, being careful not to contact leaves or stems, and water in.
Liquid solutions. Liquid fertilizers applied at the time of planting and throughout the growing season are an immediate source of nutrients. Follow the label directions carefully for dilution and application rates, keeping in mind that too much liquid fertilizer can burn plants.
Side-Dressing. Dry fertilizer is applied when plants are growing throughout the season. Scatter the fertilizer 6-8 inches from the plants on both sides. Work it into the soil and water thoroughly (dry fertilizer requires moisture to break down).
Foliar Feeding. Foliar feeding is used when a quick growth response is needed; when micronutrients such as iron or zinc are locked in the soil; or when the soil is too cold for the plants to use fertilizer applied to the soil. Foliar-applied nutrients are absorbed and used by the plant quite rapidly, beginning within minutes after application and completed within 1 to 2 days. Foliar nutrition can be a supplement to soil nutrition, but never a substitute. For instance, an application of phosphorus spray will help at transplant time in the establishment of seedlings in cold soils. For perennial plants, early spring growth is usually limited by cold soil, even when the air is warm. In cold soil, microorganisms are not active enough to convert fertilizer into nutrient forms the roots can absorb, even though the plants can utilize them. A nutrient spray to the foliage will provide needed nutrients immediately, stimulating plant growth. Liquid feeding is more of a one-time procedure, either as a transplant starter or as a foliar feeding to correct a deficiency in a major or trace element. Follow the directions carefully, as using too much foliar fertilizer can quickly burn the foliage.