How do you choose between products with the same nutrient content? The big choice is between fast and slow release of the nitrogen fraction. The percentage of the total nitrogen that is water insoluble and that which is water soluble usually is listed on the fertilizer bag. In the water soluble form the nitrogen is available quickly, and in the insoluble for it is available slowly.

A good turf fertilizer contains some of each kind of nitrogen. The slow release portion provides nitrogen over a period of time but is not available to the plant during cool weather. The soluble fraction, or fast release, will provide nitrogen almost immediately after application and during cool weather. Something approaching 30 percent to 50 percent insoluble or slow release (time released) nitrogen is suggested.

University research has shown that fall (August or September) and late fall (October, November, or December) fertilization is ideal for home lawns. Fertilization during these times will benefit lawns more than any other practice. Most homeowners place too much emphasis on spring and summer fertilization. Some fertilizer is needed during the spring and summer, however, over-application of fertilizer at these times can cause disease and other problems and result in "summer lawn nightmares.".

Disease and weed problems are usually less severe when fall and late fall fertilization are practiced. Heat and drought tolerance are usually better, thus enhancing summer lawn quality. Finally, the grass plant produces more root mass and a deeper root system, resulting in and overall healthier plant.

Lawns need to be fertilized periodically (several times) throughout the growing season. Fertilizations (feeding) should be made at eight to ten week intervals throughout the growing season. A general fertilization schedule for homeowners interested in a moderate high quality lawn is provided below.

Any fertilizer may burn the turf if applied improperly. Fast release nitrogen is more likely to burn than slow release forms. To avoid burn: 1) Do not apply more than 1 1/2 lbs. of actual nitrogen per 1,000 square feet at one time; 2) Spread uniformly; 3) Do not overlap or spill fertilizer; 4) Apply fertilizer only when foliage is dry; 5) Water after application. Pulverized materials are more likely to burn than pelleted or granulated materials.