Adios Organic Weed Killer is a newer organic weed killer that works better than others on thistles. There are a lot of organic weed and grass killers out there (like Burnout Organic Grass & Weed Killer) that work great at killing the above ground portion of plants but don't work so well at killing the roots. read more
How to Get Rid of Thistles. Three Parts: Organic Management Herbicides Long-Term Prevention Community Q&A. Thistles are very stubborn weeds, and if you do not catch them early on, they could take years to get rid of. With enough persistence, however, it is entirely possible to keep thistle in check without having to resort to drastic measures. read more
Thistle plants come from the Asteraceae plant family and include several varieties. Considered an unwanted weed by most gardeners, thistles can be controlled with homemade herbicides, uprooting and prevention. Thistle plants grow in U.S. Department of Agriculture plant hardiness zones 5 through 9. read more