If you lawn is like mine it may be looking thin, weedy and full of crab and quack grass! With a few steps you should be able to bring the turf around to have a healthy weedfree lawn for next summer.
Thin or bare areas - When the rain started after the drought most areas that are going to fill in with desirable grasses have by now or they are not going to. However depending on here you live and how much rain you had it is probable those areas died rather than just going dormant. Right now we are in a mini-drought with un-irrigated areas going dormant again but it looks as though rain is on the way.
The next couple weeks would be a great time to rake those areas with a steel rake and spread some seed. If possible lightly rake back and forth to work the seed into and past the dead material, pack down or cover with a light layer of soil as a topdressing and then pack. If it is only a couple patches covering with burlap or straw until the grass is up will help hold the moisture in to allow faster seed germination.
Even weedy areas can be seeded now and the weeds can be taken care of later in fall.
The best sunny lawn mix will have 80% kentucky bluegrass and 20% perennial ryegrass in it or up to 20% fine fescue. 100% kentucky bluegrass will work but it does take longer to germinate and emerge so the perenial rye is used as a nurse crop to help stabilize the soil and provide shade for the new bluegrass plants. For shady areas your mix should have more than 50% fine fescue in it with kentucky bluegrass and not more than 15% ryegrass. (Examples of fine fescue are creeping red, chewings and hard fescue.)
Beware of discount seed mixes that contain some or all annual ryegrass or rough bluegrass. Annual ryegrass will die over winter and rough bluegrass is not a desirable lawn mix. A perfect mix for the average lawn would be 60% kentucky blue, 30% fine fescue and 20% perennial ryegrass. This will allow the bluegrass to thrive in most of the lawn but the fescues to thrive in those few shady sites.
Weeds - During the drought weeds of all sorts took advantage of the dormant thin turf and are trying to take over. To control dandelion, clover, creeping charlie, creeping jenny, nut sedge and other perennial weeds wait until after a frost or two when the plants are weaker for better control. Even then creeping charlie may have to re-treated next spring when it starts growing again. A quality three way selective-herbicide from a reputable source will take care of the weeds. Spraying weeds is more effective than using a granular product but both should work when used according to the label and directions.
Crabgrass usually comes up in late June and early July and looks light green in color and grows laterally or nearly flat on the ground. Right now it is seeding out with spiny looking stems and seed heads. Because it is a annual it will die during the first hard frost but the seeds it produces will be there next spring waiting to germinate. The best way to treat crabgrass at this point is to remember where it came up and treat those areas with a pre-emergent weed control next spring following the directions and rates on the label.
Quackgrass is a perennial and never goes away and can only be eliminated by using a non-selective-herbicide like roundup and killing everything and starting over. Quackgrass like many weeds is a plant of opportunity filling in thin areas of your lawn. The best treatment is to have a healthy bluegrass lawn to crowd out the quack. In years of normal rain it should be a minimal problem for quality lawns. The plants there today will live for years but a pre-emergent herbicide next spring should keep more plants from establishing from seed.
Fertilizer - September is a great time to fertilize your lawn while it is actively growing to prepare it for winter and next summer. Recent research has shown that a late fall fertilization is not as effective as once thought because it is not taken up by the plant. The amount and type of fertilizer needed really depends on your unique lawn so visit a vendor you trust and ask for a recommendation.
Fertilizer is sold as a 10-10-10 or 18-5-9 etc. The most important number is the first one or the amount of Nitrogen or "N". In a 18-5-9 fertilizer there would be 18lbs of nitrogen in 100lbs of product not the bag you purchase. Nitrogen comes in two forms: WIN or water insoluble nitrogen and WSN water soluble fertilizer. Water soluble fertilizer is normally considered quick release and will only last 3 to 4 weeks. WSN should make up 20 to 50% of the total nitrogen
The second number is for phosphorus or "P" and in most cases will be 0 due to state regulations and the fact most Wisconsin soils have enough phosphorus in them. For the golf course we take soil tests to check the amount of phosphorus and by law that is the only way we can apply it.
The third number is for potassium or "K" and is very important for plant health during stressfull times. In established lawns not much is needed but only a soil test can tell for sure.
Irrigation - Healthy lawns normally can thrive on just rain but in a year like this some supplemental irrigation may be needed for recovery or in future years to keep grass alive during long droughts. For established lawns and trees it is best to water heavy once a week to ten days rather than light every couple days. For this fall unless we get a above average amount of rain it would be a great time to water your established trees deeply. Let a slow running hose soak the area or use a soaker hose for a couple hours per tree to allow the water to penetrate deeply.
A healthy lawn brightens a homes landscape and increases home value. Yours may have taken a beating this summer but with a little time and work can be looking great by next spring.
