Lawn Care Tips for Early Summer
As we transition from spring into summer over the coming weeks, there are a number of lawn care practices that will help maintain a healthy lawn.
Fertilization: Depending on management practices and environmental factors, most Minnesota home lawns require between 1 and 4 pounds of Nitrogen (N) per 1000 square feet of lawn, annually. This annual amount should be separated into multiple applications of no more than 1 pound of N per 1000 square feet in any single application. Fall-applied fertilizer applications are generally best for the long-term health of the plant, but spring applications are common also, especially when using fertilizer in conjunction with weed control products.
Crabgrass: Crabgrass is a warm season, annual plant and is a common nuisance in many home lawns. As a warm-season annual, crabgrass usually germinates near the end of May. The pre-emergence crabgrass herbicide that is often included with fertilizer applications in early spring will not work on crabgrass that has germinated. So, if you are noticing young crabgrass plants in your lawn, it will be necessary to switch to a post-emergence herbicide in order to control the weed.
One common post-emergence herbicide that is quite effective on crabgrass is quinclorac. This herbicide is usually found in combination with broadleaf herbicides. To control both broadleaf weeds and crabgrass, look for a broadleaf weed killer that also lists quinclorac as one of the active ingredients. Other active ingredients that can effectively control crabgrass include monosodium methanearsonate (MSMA), disodium methanearsonate (DSMA), and calcium acid methanearsonate (CMA or CAMA).
Avoid applying these products when lawns are under heat or drought stress, as they may negatively affect stressed lawns. Post-emergence crabgrass herbicides are most effective on young plants, so it is important to control existing crabgrass as early as possible.
Broadleaf weeds: There are a number of products available for control of broadleaf lawn weeds and most of them are equally effective on the more common plants. For those weeds that are more difficult to control (clover, violet, and others), look for products containing triclopyr as an active ingredient. When choosing broadleaf weed herbicides, always double-check that the product is safe to use on lawns!
Other Cultural Practices: Finally, as we move into summer, most lawns will benefit from a slightly higher mower setting. Mowing to a height of 2.5 inches or more will benefit the lawn by encouraging a healthier root system. Longer grass also helps shade the soil to conserve moisture and the healthier lawn will help reduce competition from weeds.
Of course, none of the practices mentioned here will show much benefit if the lawn does not receive adequate water. Ideally, lawns should receive about one inch of either rainfall or irrigation each week. For more information about home lawn care, visit: http://z.umn.edu/m79 or call your local Extension office.