“I am having the hardest time killing trumpet vines & they have taken over my yard. I use roundup every year, but it’s not killing the root system.” Question from Rosie of Wichita, Kansas
Answer: Red trumpet vine (Campsis radicans) is a beautiful native vine with giant, trumpet-shaped, orange-red flowers loved by hummingbirds, but as you have discovered, it is best left for roadside fencelines and natural areas. The vine becomes monstrous and just takes over home landscapes and gardens. Glyphosate, or any other home chemical means, won’t kill it. It requires the toughest measures and a lot of elbow grease to remove.
Trumpet vine is big and woody like a tree, so you have to remove it like a tree. If the vine is still too big, use loppers, and/or pruners to cut it all back. If it’s just popping up everywhere in your lawn, and/or still has a large stump, take a sharp spade and/or mattock and start digging. You’ll have to pull up all the roots, stems, and runners, but it will be a job well worth it. Once you have it all up, you won’t have to deal with it again, hopefully. The occasional sprout may pop up here and there, in which case dig, don’t spray.
A gentler rambling perennial vine with just as much hummingbird attraction is red honeysuckle (Lonicera sempervirens). It is easily cut back and kept in place. Check out the extra-beautiful variety ‘Major Wheeler’.
Black Gold Horticulturist