Yellow nutgrass is considered an invasive weed in some states.
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Nutgrass (Cyperus rotundus L.) is classified as a noxious weed in four states (California, Oregon, Washington and Arkansas) and is considered an invasive or nuisance weed in several others. It is often called "nutsedge" and can be classified as purple or yellow. This short, unassuming plant is actually very difficult to control, which is something you need to carefully consider before choosing to plant and grow it.
Choose a sunny, moist location to plant your nutgrass. Nutgrass does not tolerate drought or shady conditions very well. In warm, sunny locations, however, one tuber can produce as much as 2,000 new tubers in one growing season, which is why some states consider it a noxious weed.
Plant your nutgrass tuber only two inches under the soil. Nutgrass is a shallow-rooted plant. Make sure you establish it away from other plants, as it does not compete well and can be overgrown by crops. There is no need to fertilize it.
Water your nutgrass tuber during extended hot, dry spells that last over a week.
Protect nutgrass from a late frost. Frost will damage the new shoots if they appear in the spring before the last frost. If there is a danger of frost, simply put a layer of mulch over the new shoots.
Control your nutgrass. In the right conditions, nutgrass spreads very rapidly. It is not easily killed by chemicals. The best way to control the unwanted spread of nutgrass is to till it (exposing the tuber) during extended dry spells, then remove the tuber and any parts of the plant by hand.