Last summer and early fall, our lawn was choked with lespedeza. How can it be best prevented/controlled during this coming growing season without damaging the grass? Is a pre-emergent product recommended? If so what? Sold where? Should a lawn fertilizer be used soon before or after the herbicide?
Virginia Beach Virginia
Controlling lespedeza in a lawn can be somewhat difficult. A pre-emergent can help but there are probably thousands to millions of seeds in the soil and they don't all germinate at the same time.
The best practice to get rid of most of this lawn pest is to use an herbicide that contains 2,4-D plus Dicamba plus Tryclopyr or a combination of two of them. A good full service garden center should be able to direct you to an appropriate product. Be sure it is listed as safe to use on lawn grasses.
Timing should be when the weed is young but actively growing. In your area that would usually be in mid April to early May. You want to make the application before the weed flowers and sets seeds. Read the label on the herbicide to see what it says about a second spraying in the same season. Some can be used and some should have a longer period of time between applications.
You will most likely get fairly decent die back of the weed this season, but it will come back next year from the seeds that are still present in the soil. Therefore, be prepared to do this again next year. If the lawn is looking better, less weed infested, you might be able to do spot treatments next year instead of wide spread spraying.
Use of a weed and feed product may help eliminate some of the problem but feeding a fescue lawn in the spring is generally not recommended. If you have a warm season grass such as zoysia or bermuda, then spring feeding and weeding at the same time is okay.
Whatever products you use, please be sure to read and follow the label directions carefully. They are there to help you get the best results from the product (more is NOT better!) and for the protection and safety of the applicant as well as anyone else in the area. It also helps prevent their overuse and potential pollution by these products.
This publication from Virginia Tech gives good advice on spring and summer care of lawns in Virginia. If you have additional questions you may contact your local office of Virginia Cooperative Extension which can be found on this website or use the reply feature within this email.
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