My entire back flowerbed has been taken over by horsetail (Equisetum). It has even gone around the corner to the front of the house and out into the yard. What is the best way to eradicate it? I was also wondering if cedar wood chips can be used for mulch in the garden or flowerbeds.
The Gardener’s Answer
Hi, Lisa: Horsetail (Equisetum) is an aggressive spreader that is difficult to control once established. This plant produces underground rhizomes that spread rapidly and produce reed-like, upright foliage. These natives do have some beneficial aspects but not when it is taking over a flower bed. Early prevention is important. The longer it is allowed to spread the more difficult it will be to eradicate. Hand digging is not ideal and not an option in an established landscape bed without damaging your desirable plants. In this situation you can cut back all of the existing foliage. This will not kill the roots but will prevent further spores from forming/ germinating and will deprive the plant from receiving essential nutrients. Any new growth that appears can be treated with an herbicide. The results of chemical control are mixed in terms of effectiveness. Herbicides that are registered to control top growth of horsetail include glyphosate and 2,4-D. Any product that has this listed as the active ingredient will work. As with any product it is important to follow product application instructions. Do not spray since these products are non-selective and will damage your other plants in the landscape. You can dip a paint brush into the herbicide and paint the foliage. Be sure to wear gloves. It will likely take several seasons to get the horsetail under control but the sooner you start, the less tedious it will be. If this area is irrigated you will want to cut back on the moisture it receives since this plant thrives in wet soil.
As for the cedar chips, they can be used as mulch as long as the tree was not diseased. If the tree was removed because of disease issues, the chips should be discarded or composted for a least a year before incorporating them into the garden. When used as mulch, apply 2-3 inches thick. Any thicker and we are creating a nice environment for insects and disease to live. It is also important to keep the mulch off the lower parts of the plant. The main purpose of using any mulch is to stabilize soil temperatures, keep the weeds down, and the moisture in. It is also helpful in preventing soil-born diseases from splashing up onto the foliage. I hope this helpful. Please let me know if you have any follow-up questions.
Kentucky Living-Ask the Gardener