Turfgrass Species

By Chuck Martin, Dow Gardens Horticulturist

The goal in creating a beautiful lawn is to have uniformity.  We want our lawns to look like our living room carpet.  Just like the carpeting where we frown at any stains, we get annoyed at stains in our lawns.  Instead of pet, juice and beer stains on our carpet, the lawn is “stained” by weeds and dog urine.

It is hard to believe that our uniform lawns, are in fact made up of grass seed sold as a mixture of different species.  The grass seed breeders have developed seed that grows into plants that resemble Kentucky bluegrass so much it is hard to detect the difference with the laymen’s eye.

Of course Kentucky bluegrass is the most important turfgrass grown in our lawns.  It is a fine textured, long lasting turfgrass that is worshipped by most homeowners.  It loves cooler weather with temperatures between 65 and 75 degrees.  During hot dry periods Kentucky bluegrass can easily go dormant.

Kentucky bluegrass grows laterally by producing rhizomes.  A rhizome is an underground stem that when the conditions are correct will branch many times and produce a thick lawn.

Many people believe that Kentucky bluegrass is native of the state of Kentucky.  This makes it seem patriotic to grow Kentucky bluegrass.  Kentucky bluegrass is actually native of most of Europe.  In fact it is considered an invasive weed in America’s beautiful prairies.  So if you are planting Kentucky bluegrass because you believe it your patriotic duty, I am sorry to ruin this illusion.

Kentucky bluegrass will not tolerate heavy shade.  It prefers a neutral soil and will die out if the soil is too acidic or too alkaline.  Establishment and germination rates are slow compared with other species of turfgrass.  Perennial ryegrass is often added to Kentucky bluegrass seed because of its quicker germination and establishment.

Perennial ryegrass is a fine-textured species that has the potential to form a thick lawn through lateral growth called tilling.  Perennial ryegrass is more drought tolerant than Kentucky bluegrass.  It does still require irrigation in the hot months of the summer.  Many new and improved varieties of perennial ryegrass have been developed in recent years.  These new varieties are disease resistant, have the same texture as Kentucky bluegrass, and better density than the older varieties.  When mixing with Kentucky bluegrass, the perennial rye grass component should not exceed more than 50% of the mixture.

As I stated before Kentucky bluegrass does not do well in shade.  There are now varieties that tolerate shade.  Tolerate is the key word.  Kentucky bluegrass tolerates shade like when you tolerate your neighbor’s lack of a muffler at 6 o clock in the morning. 

Shade tolerant seed mixtures usually contain red, hard, and chewings fescues.  These are fine fescue types and grow well under shade.  Keep in mind that these fine fescues don’t require as much fertilizer as Kentucky bluegrass and will decline if they are over fertilized.  Reduce your fertilizer when you grow turfgrass in the shade.  This will create a healthier lawn.

If you need turfgrass that is low maintenance and you don’t mind a coarser texture grass, the type of seed that might be recommended is tall fescue.  In visiting Washington DC, I noticed the White House lawn was tall fescue.  I am sure many of you have noticed this fact while visiting our president.  The breeders have created many new varieties that are finer textured and make a beautiful lawn.

The reason I am writing about turfgrass seed in September is this is the best time of the year to establish a cool season lawn.  The soil is warm for germination, the temperatures are cool and we are getting some nice rain.  If fact this is a great time to do any cultural practices to your lawn to build up its density and make it look like your living room carpet.