Turfgrass establishment from seed can be a challenging endeavor. One key to successful establishment is the use of high-quality seed that is best adapted to each individual site. In the turfgrass industry, there are mixtures and blends of seed. A mixture is a combination of multiple species, while a blend is a combination of cultivars within the same species. For example, Kentucky bluegrass and perennial ryegrass in the same bag of seed would be a mixture of seed. However, a blend is a combination of cultivars of the same species such as Midnight and America Kentucky bluegrass.
Seed Labeling Information
In most cases, the seed label is the best source of information pertaining to seed quality. By law, each seed package sold in the US must be labeled truthfully. However, labeling does have its downfalls and all consumers must be aware of the potential loopholes. There are no bargains when it comes to turfgrass seed. For a higher quality seed, you will have to spend a few more dollars. The availability of high-quality seed is limited and ultimately expensive to produce, which has led to the production of poor-quality seed.
The germination percentage should also be considered when purchasing seed. Seed should never have labeled germination rate below 85%. In addition to the labeled germination rate, time also play a huge factor in germination percentage. Seed germination decreases over time and germination rates may have decreased significantly since the original testing date.
The percentage of inert matter tells you the weight of all nonseed material in the bag. Weed seed percentage is very important and is the total weight of all the weeds. In most cases, noxious weeds are of little concern in turfgrass because of the continuous mowing and defoliation following germination. Quackgrass is one of the few exceptions.
The biggest loophole and seed contamination occurs in the percentage by weight of other crop seeds. Most of the worst weeds in turf are perennial grasses. Most of these perennial grasses are produced commercially, which group them into the other crop seed category rather than noxious weeds. Grasses such as bromegrass and tall fescue are particular problems. The species list of “other crops” is not usually listed on the label and it is hard to identify their potential impact in turfgrass seeding. To prevent issues you should always use high-quality seed from a reputable dealer. There are no bargains in seed and it is advisable to pay more now because it will save you money and headaches in the long-run.
One example of this can be seen below with a yard contaminated with common perennial ryegrass. Common perennial ryegrass is usually found in cheaper seed mixes. It is produced at a lower cost than many of your elite perennial ryegrass cultivars. The common perennial ryegrass can be unsightly and drastically reduce turf quality. It has many of the same identification characteristics that you would consider a more desirable perennial ryegrass to have. Folded vernation (once closely observed from a microscope), short to midsized auricles possible, bunch type growth, potential red stem base (is absent in pictures below), divided collar, and a pointed leaf blade that rolls out of the sheath. Common perennial ryegrass however lacks the allure features of the more elite perennial ryegrass cultivars. It often grows awry and is perceived as a nuisance and weed species as seen in the pictures below.