Michigan State University Turfgrass Scienceturf.msu.edu

Germination testing is an important component of seed evaluation.
Germination testing is an important component of seed evaluation.

Purchasing Quality Turfgrass Seed: Read the Label  •  E0014TURF

K. W. Frank

Purchasing quality turfgrass seed for reestablishing lawns or establishing new lawns is critical to the future success of the lawn. Several key words often seen on bags of lawn seed are common indicators of what turfgrass species the bag contains.

Seed bags that contain the phrase “quick green” or “fast grass” often contain annual ryegrass. Annual ryegrass is just that - an annual. Annual ryegrass germinates rapidly and will grow throughout the summer but in almost all instances will die in the winter and leave the area bare the following year. In some cases, annual ryegrass may survive for a second year, but normally this is not the case. The normal use of annual ryegrass is as a cover or nurse crop for the desired turfgrass species.

Another keyword often observed on seed bags is “tough” or for “high traffic areas”. These phrases often indicate the bag contains tall fescue. Tall fescue is a very drought-tolerant, deep-rooted grass whose use in Michigan is slowly increasing. Establishing an entire lawn of tall fescue should give good results, but homeowners should use caution when reseeding small areas in a Kentucky bluegrass lawn. It’s wise to try a small area first because one of the biggest differences between tall fescue and Kentucky bluegrass is the leaf blade width or texture. Most of the new improved tall fescues have narrow leaf blades that are not much different from those of Kentucky bluegrass, but others may not blend with the existing bluegrass at all.

The most common descriptions of turfgrass seed relate to sun and shade conditions. The shade mix is usually composed of Kentucky bluegrass and some combination of fine fescues (hard, chewings or sheep fescue). All of the fine fescues have very fine leaf blades and perform well in shaded environments. The sunny mix is usually composed of Kentucky bluegrass, perennial ryegrass and creeping red fescue.

Tips for Reading a Seed Label

To choose quality turfgrass seed, you need to understand the information presented on the seed label. The seed label — or tag, as it may be referred to — is usually found on the back of a bag of seed. The label contains valuable information including the cultivars, purity, germination percentage, crop seed, weed seed, inert material, noxious weeds and date tested.

Cultivars: The simplest tip is to look for specific cultivar names, not only “Kentucky bluegrass” or “tall fescue”. Named cultivars are superior in many traits to the common types.

Purity: The percent by weight of the particular cultivar seed. For our example, Mackinac Kentucky bluegrass has a purity of 75 percent.

Germination: The percent of pure seed that germinates under ideal conditions. Simple guidelines are never to purchase seed with less than 70 percent germination. A higher germination percentage is better.

Crop: “Crop” is the seed of any other commercially grown grass crop. Crop could include grasses such as orchardgrass, timothy, clover or bentgrass. High quality turfgrass seed should contain no other crop seed or, at the most, 1 percent.

Weed: The percent by weight of weed seed. This is any seed that is not pure or crop seed. Ideally, seed should contain no weed seed, but some weed seed always seems to find its way through the screening process, so look for a value less than 1 percent.

Inert: The percent by weight of material other than seed. This might include chaff, corn cobs, sand or soil. Look for a value less than 4 percent.

Noxious Weeds: These are weeds that are particularly difficult to control and are declared noxious by some states. It is illegal to sell seed that contains noxious weeds. If noxious weed are present, they must be listed by name.

Date Tested: This is the date the seed was tested. Look for seed that was tested within the previous 12 months.

Sample Seed Label

XYZ Lawn Mixture
Pure SeedCultivarGerminationOrigin
75% Mackinac Kentucky bluegrass 90% Michigan
23.25% Traverse City Perennial ryegrass 87% Michigan
1% Inert Matter
0.50% Other Crop
0.25% Weed Seed
Noxious Weeds: None
Test Date: 11/01