Grass Seed Ratings

Basic Criteria

• Basic grass ratings compare resistance to variables such as diseases, weeds and drought. Growing conditions such as light factors and other environmental stresses along with color intensities and the denseness of the grass are also taken into account. Uniformity is another aspect that is measured when rating a particular grass seed. Other factors include the maintenance needed such as amount of watering, mowing and fertilizing necessary to keep the grass in good condition.

NTEP Criteria

• Researchers, turfgrass breeders and extension specialists consult NTEP in regard to their grass seed ratings. Sales and ads from seed companies use the NTEP ratings when promoting products. The NTEP evaluation is based on a subjective measure of functional and aesthetic use, but primarily visual estimates performed by a number of trained observers.

NTEP Quality

• The NTEP rates seeds on a scale from 1 to 9 with 9 being the best and 1 being dead. An acceptable grass seed rating within NTEP is 6 or above. Both functional and aesthetic aspects are evaluated for the NTEP ratings. These ratings are also based on a combination of uniformity, color, texture, density, environmental stress and resistance to disease.

NTEP Seedling Ratings

• Seedlings are visually evaluated on vigor, again using the 1 to 9 rating scale with 9 being maximum vigor. Other aspects include ground cover estimate percentage and the relative speed the seedling arrives at maturity for sod.