Published for the News-Review on March 21, 2025
By: Janet Bitter
Question: My friend has a patch of horsetails around her garden pond. I’m thinking of getting some. Are they easy to grow?
Answer: Whoa, partner! (Sorry!) About a year ago, I wrote an article on weeds. What I tried to convey to Douglas County gardeners is that sometimes one person’s prize plant is another person’s problem! Horsetails certainly fall into that category, which I will explain below. Sometimes we have plants in our yards that are somewhat attractive, but we don’t remember planting them and wonder about their culture and care. Often, these plants spread easily and may be taking over sections of our planting beds where we don’t want them.
Horsetails belong to the genus Equisetum – the only living genus of the entire subclass Equistaceae, which for over 100 million years dominated the understory of late Paleozoic forests. Modern horsetails first appeared during the Jurassic period. Within the genius Equisetum there are several species you may come across: E. arvense, or field horsetail, and E. telmateia, or giant horsetail, are two that are common, but I don’t think anyone would ever advise planting these. Both appear on various states’ noxious weed lists. Giant horsetail is listed as a noxious weed in Oregon. All plants in this genus are toxic to livestock. (Incidentally, did you notice that the Latin genus name sounds suspiciously like equine? That’s not a coincidence. Equisetum is derived from the Latin equus (‘horse’) + seta (‘bristle’).)
The type of horsetail I inherited in my own yard is Equisetum hyemale, also called scouring horsetail or scouring rush. The reason E. hyemale is called scouring horsetail is because it contains high concentrations of silica. Native Americans used this plant for polishing or scouring. It is sometimes marketed as an ornamental to be used near garden water features. I assume you mean the scouring horsetail is the one your friend has. Should you plant this?
There’s a good reason this genus has survived millions of years. It is extremely tough and hard to eradicate if it gets going in your yard. It will grow in almost any soil, prefers to be near water and can even take standing water. The rhizomes can be found up to 3 feet below the surface. It is so invasive that it should only be planted in containers (screened with fine mesh to prevent rhizomes from escaping the container) or planted in a sunken container in the ground and monitored for escapees. If, like me, you are an unfortunate gardener with wild horsetails galloping all over your garden, you can try to eradicate them by pulling new growth in the spring, but this will be a task you need to deal with for many years. I would not advise planting scouring horsetail unless it is in a container as described.
A quick search of the internet shows sellers offering all these plants. Always do the research before planting something you are not familiar with—you may avoid a huge problem later for yourselves, your neighbors, and even your pets/livestock. Hopefully, you are not the unlucky gardener with these problem plants already in your own yard. Be persistent if you are trying to control them and remember their toxicities. Happy gardening!
Do you have a gardening or insect question? Contact the Douglas County Master Gardeners at douglasmg@oregonstate.edu or 541-672-4461 or visit 1134 SE Douglas Ave., Roseburg. Douglas County Master Gardeners are trained volunteers who help the OSU Extension Service serve the people of Douglas County.