After a long winter cooped up in the house, many homeowners welcome the first chance to get out and do some work in the lawn. There's a natural inclination to start spreading all sorts of treatments on the lawn, but there's a time and place for everything.
Types of Lawns
Turf grasses can be divided into two groups, cool-season grasses and warm-season grasses. It's important to know which you have--the cultural practices for each group are quite different. In general, areas with mild winters and hot summers have warm-season lawns and areas with milder summers and harsh winters have cool-season lawns. There's a big chunk of the country, roughly from southern New Jersey south to South Carolina and west to include most of Kansas, that's called the transition zone. In the transition zone, you'll need to know or investigate your grass type--both types are widely used.
Cornell University in New York, the University of Missouri Extension Service and the Virginia Cooperative Extension all warn against fertilizing both cool-season and warm-season grasses early in the spring. Cool-season turf has a natural inclination toward rapid growth at this time of year, and pushing that even more by feeding the lawn can lead to maintenance headaches and potential disease problems. Warm-season turf will still be dormant, making fertilization in the early spring a waste of time and money.
Spot treat broadleaf weeds with selective herbicide as soon as those weeds show sign of breaking dormancy. Apply pre-emergent weed control--often referred to as "crabgrass preventer"--about the time forsythia blooms. If you're looking for a natural approach to crabgrass control, Iowa State University has proven that applying corn gluten meal at a rate of 20 lbs. per 1,000 square feet is effective against crabgrass.
Texas A&M recommends fertilizer for St. Augustine in the early spring. This seemingly contradictory advice really isn't. Warm-season turf should be fertilized once it is actively growing. Where St. Augustine is used (mainly along the Gulf Coast and in Florida), it is usually actively growing by late February or early March. The same can be said for other warm-season species in the deep South. If it is green and actively growing, start fertilizing at a rate of 1/2 to 1 lb. of nitrogen per 1,000 square feet.
If you haven't had your soil analyzed recently, early spring is a great time to get that done.
For both turf types, move your mower 1/2 inch lower than normal for the first two cuttings of the season. When cool-season turf is actively growing and healthy, aerate the lawn with a core aerator.
When spring growth in cool-season turf starts to slow, apply fertilizer at a rate recommended for your grass species. Aerate warm-season turf once it has been out of dormancy and growing for two or three weeks. Fertilize warm-season turf a few days after aeration.
Preparing for Spring
Fall is the most important time of year to work in your lawn. A beautiful lawn in April starts in October. If you only fertilize your cool-season lawn once per year, do it between mid-September and mid-October. Warm-season turf should not be fertilized within four weeks of the return of cool weather. In the transition zone, that means stop fertilizing in August. In the deep South, continue until October.
For both types of turf, fall broadleaf control will give you a much more attractive lawn when warm weather returns. Don't let leaves lay on the turf all winter. Mulch them into the lawn or rake them up.