UNL Extension — helping you turn knowledge into "know how"
Healthy Lawns More Resistant to Pests
by Don Janssen, UNL Extension Educator
Lawns requiring frequent pesticide use, in particular herbicides, may have an underlying problem that is causing the repeated invasions of pests such as weeds. Correcting the problem leads to a healthier lawn that can resist weed invasions.
For example, good soil conditions are important for healthy lawns. Many lawns are growing on soils high in clay, compacted, and poorly drained. Aerating and topdressing with organic matter may improve these conditions. Another option is starting over and amending clay soils with organic matter. Thoroughly preparing soils before seeding or sodding is critical.
Make sure the proper grass species is used on the site. Full sun and sun/shade environments call for different grasses. In addition, consider the standard of quality desired and intended use of the site. Each has a role in what grass to select. Kentucky bluegrass is the primary species for lawns in full sun. For shade areas, shade-tolerant Kentucky bluegrass cultivars are commonly mixed with fine fescues or turf-type tall fescues.
Cultural practices also play a big role in the health of the lawn and need for pesticides. Proper watering includes irrigating as lawns need it and getting moisture down into the root zone. Proper fertilizing includes supplying adequate nutrients and proper soil pH. In particular, avoid excess or lack of nitrogen, fertilize during cooler weather (especially early and late fall) and use controlled-release nitrogen fertilizers. Don't apply high rates of nitrogen in spring. Proper mowing has a major impact on lawn health. Many lawns are mowed too short, allowing weeds to invade and other problems to appear. Mow between 2 and 3 inches and mow often enough so no more than one-third of the leaf blade is removed in any one cutting.
Manage lawn stress factors such as thatch, shade, and soil compaction. Core aerating on a regular basis is an excellent practice to consider, in particular for sodded lawns over clay soils. Spring and fall are good times to aerate.
Occasionally, problems will still come up that require special management. Start by identifying the problem, then look at control options; both cultural and chemical. When using pesticides read, understand, and follow all label directions.
University of Nebraska-Lincoln Extension in Lancaster County is your on-line yard and garden educational resource. The information on this Web site is valid for residents of southeastern Nebraska. It may or may not apply in your area. If you live outside southeastern Nebraska, visit your local Extension office
Contact Information University of Nebraska-Lincoln
in Lancaster County
Web site: lancaster.unl.edu
444 Cherrycreek Road, Suite A, Lincoln, NE 68528 | 402-441-7180