Bamboos (Bambusa spp., Phyllostachys spp.), large perennial members of the grass family, might make attractive screens, hedges, windbreaks or specimens, but these beautiful plants are also one of the hardest ornamentals to control once they've escaped their designated growing areas. They're hardy in U.S. Department of Agriculture plant hardiness zones 4 to 11, depending on type. Although some species are well-behaved, many bamboos are aggressive creepers that attempt to take over entire landscapes -- cracking sidewalks, damaging foundations and overtaking ponds, flowerbeds or streams as they spread. Repeatedly digging, cutting and spraying bamboo can eventually help you get rid of unwanted plants.
Approximately 1,200 bamboo species exist, with each one characterized as either running or clumping. Clumping bamboo bears short, compact roots that spread slowly, typically just a few inches every year. Getting rid of clumping bamboo usually requires little more than grubbing it out with a garden spade. Running bamboo plants, on the other hand, use their tough underground stems, called rhizomes, to spread up to 12 inches a day. This aggressive spreading action allows the mother plant to send up new shoots as far as 100 feet away. Removing a running bamboo plant usually requires frequent digging, cutting and herbicidal treatments.
You can often remove bamboo plants by digging them out of the soil, but it might take several seasons for your labor to pay off. Make the digging process easier by moistening the soil with a garden hose beforehand. Break up the soil around the primary bamboo plant, digging at least 18 inches deep to get to the shallow, horizontal roots. Grub out the main plant up by lifting it up from underneath with a garden spade or shovel. Examine the root system to make sure no pieces broke off during the process. If they did, dig in a circle around the hole to find the remaining rhizomes. Even a tiny piece of stem can send up a new bamboo shoot. Place plant debris in a plastic trash bag and throw it in a covered garbage can. Monitor the site closely, promptly digging up any new growth.
Frequently cutting bamboo stems down to the soil line will eventually kill the entire plant. Pruning shears can typically handle small stems, but you might need a saw or a machete to cut through the large, tough bamboo stalks. New shoots will resprout from the rhizomes, so promptly cut down the regrowth when it reaches between 20 and 24 inches high. Repeated cutting removes the leaves required for photosynthesis, so the plant must turn to the food reserves stored in its root system. Once it uses up the reserves, the bamboo plant can't send up new shoots, and the underground stems will rot and die. The cutting process typically takes one to two years to work. Be sure to sterilize all gardening tools when you're finished cutting the bamboo.
Glyphosate-based herbicides are the most effective bamboo killers available to homeowners, but use a solution containing a 41 percent concentration of the chemical for optimal control results. For foliar treatments of actively growing leaves, mix 6 fluid ounces of glyphosate concentrate for every gallon of water. Use a handheld garden sprayer to uniformly coat the leaves until they glisten with moisture. Repeat the application once the bamboo shoots send out new leaves. Wear protective eye covering and clothing, and keep people and pets out of the treatment area until the solution dries, or at least six hours. Spray only on calm days so the solution doesn't drift to other plants. Glyphosate kills or damages any broadleaf plants or grass it lands on. Do not water the treatment area for seven to 10 days to avoid injuring the roots of nearby desirable plants.
Cut and Spray It
Get rid of large bamboo plants using the cut-and-spray method. This requires cutting each stem down to within 6 inches of the soil line and immediately spraying the cut stem with a 5 percent glyphosate solution, or 6 fluid ounces of product for every 1 gallon of water. If you're working in a small area with a lot of desirable plants, use a paintbrush to carefully coat the cut stems with the solution. Allow the bamboo to regrow to about 18 inches tall before treating it again. You'll need to complete as many as four "cut-and-spray" treatments before getting rid of unwanted bamboo plants. As always, carefully read and follow the application instructions and safety precautions on the herbicide product's label before use.