Answer: Some of the suggestions made by experts on how to control this pest include making sure the drainage of the soil is good. It is also supposed that it can be shaded out by vegetation around it. Populations of viable nutgrass can be dramatically reduced by repeatedly turning the soil at one to two-week intervals to expose the tubers to the sun. Unfortunately, in your flower bed situation, these are probably not terribly practical. As noted above, the tubers are resistant to most herbicides, and if the blades of "grass" are broken off, the tuber carries on, and one to two inches of new growth will be visible within a day. Oh, and it's one of the few plants that plastic mulches cannot affect. I don't have personal experience but I've heard that a product from Monsanto called Manage is effective against nutgrass. You might do a web search or find a product label to read. Hope it's available in your area. Best of luck with your garden!
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