Fertilizers Used in Sod Farms

Soil Analysis

• The type of fertilizer and fertilization process used on a sod farm depends on the soil. Sod farm operators regularly analyze soil to determine what nutrients are present and what nutrients are lacking in the soil. Based on these results, the sod farmer can adjust the fertilizer type to make up for missing elements and leave out elements that already are present naturally. A soil analysis also helps farmers determine how often they should fertilize the type of sod they grow.

Slow-Release Nitrogen Fertilizing

• Sod requires fertilizers, especially if the soil lacks nitrogen. Sod farms use regular nitrogen fertilizer, which shows results quickly but doesn't last long; or slow-release nitrogen fertilizer. Other label names for this kind of fertilizer are controlled release, polymer coated or sulphur coated. Slow-release nitrogen is absorbed into the sod over an extended time. Sod growers have to balance the need for their grass to grow quickly against root growth, which can be reduced by too much nitrogen.

Phosphorus Fertilization

• Sod needs phosphorus because it enables energy transfer within the plant and helps establish the sod's root systems. Some sod, such as bahia grass, can show symptoms of phosphorus deficiency during low-light or cool weather conditions in early spring when the grass is growing faster than its root system. Regular phosphorus fertilization and good growing conditions prevent these problems.

Potassium Fertilization

• Like phosphorus, potassium also encourages root growth. It is vital to build disease resistance and cold-weather tolerance. The nutrient is important in developing the mat of the sod, which is needed to lift the sod and transplant it into another landscape. Slightly elevated potassium levels in the soil do not seem to negatively affect the sod production. The timing for both potassium and phosphorus application vary with the growing area. In Tennessee, for example, they would be applied before planting and again as a boost to seedlings.