How Do I Get Rid Of Nutsedge?

Q: A load of topsoil I bought for my flower garden brought in nutsedge tubers as well. This year I covered the soil with landscape cloth and planted zinnias in holes I poked in it. How long do I have to keep the area covered to fully annihilate the nutsedge? 

A: According to one source, nutsedge tubers remain viable in the soil for several years. The weed is impossible to control by pulling because tubers easily separate from the base of the plant when you tug on the leaves. I got control of the invader in my garden by using a water-powered weeder (http://www.walterreeves.com/gardening-q-and-a/water-powered-weeder/). It injects water under pressure next to the base of any plant. It is easy to pull a nutsedge plant, tubers and all, from the soil slurry the weeder makes. It’s a great tool to use against wild onions, wild violet, and dandelion.