Viewing post #481289 by virginiarose

katherine2 said:Thistles are known to be a relatively difficult weed to kill; however, to prevent the spread of more thistles, one should attempt to kill existing thistles before their seeding season. Since thistle root systems can continually grow new thistle plants, the best way to kill them in a single effort is to first cut the plants down, as close to the root as possible. Then, cover the area where the plant had been with a thick, dark covering, such as a tarp or old carpet, which will not allow sunlight to penetrate or new plants to spring up. Over several weeks, this should kill the plant.