Let's look at lawns

By John Fulton

[September 05, 2012]  I covered some basics on lawns a few weeks ago, but today I would like to get more specific on recommendations. Because of the drought, there are many things to consider, and we are in the prime time for fall lawn work -- assuming it rains with some frequency.

I guess it takes a hurricane to deliver some significant moisture. Many areas reported over an inch and a half, and some over 5 inches. Once again it depended on what part of the clouds you were under, but at least everyone received some decent moisture.

The other ingredient needed for lawn recoveries for most area lawns would be cooler temperatures. About 98 percent of our lawns are cool-season lawns, based with Kentucky bluegrass, red or chewings fescue, or perennial ryegrass. Some recovery was under way, and then some rather warm temperatures stalled it again.

With things beginning to green up, we can now start to assess the damage and make plans to correct the situation. Areas that are green and growing are obvious. You may have to look closer to check areas that still appear to be a large, brown or gray spot. Look closely in those areas for small green shoots coming from the lower portions of the plant. This would mean the regrowth is coming from the roots or crowns of the plants. If you don't see any regrowth by Sept. 10, seed will be required to re-establish green grass in those areas.

As for the number of grass plants in an area, the main thing is to have something green in most areas. If you have brown areas larger than a dinner plate, it will take more than one season to fill in. Smaller areas, smaller than a dinner plate, can fill in during one fall or spring season. It doesn't take many "sprigs" to bring back your green lawn. The rate of seed application should be 2 pounds per 1,000 square feet to "thicken things up" and 4 pounds if there isn't anything there.

The use of herbicides for weed control will also come into play. If you are going to do any seeding, forget the herbicides this fall. They will affect the small grass plants as they germinate. The rule of thumb is you should mow new grass from seed three times before using herbicides to control broadleaf weeds.

If you want to wait until spring to try putting some new seed down, or if you have enough green to wait it out, fall is a great time to work on perennial weeds such as dandelions, plantain and violets. The end of September is usually a good time to apply herbicides, but it has to be before a killing frost. Also, make sure the product you use will control the weeds you are after. Check the product label for control information.

Fertilizer is another key component to fall recovery. A product that supplies a pound of actual nitrogen and potassium per 1,000 square feet is needed. The phosphorus isn't as important for grass plants but may be in fertilizers you purchase. Something like 8 pounds of 12-12-12 per 1,000 square feet would be needed. This should be applied as soon as possible and should be watered in quickly if rain doesn't do the job.

To really thicken up the lawn -- and mow until about Christmas as the downside -- do this again Oct. 1 and Nov. 1. This will be fairly expensive with current fertilizer prices, and you may have problems with watering in late fall because of freezing temperatures. If one shot of fertilizer gives you an adequate boost, stick with the one application.

[By JOHN FULTON, University of Illinois Extension]