Winter horsetail, like pond horsetail or field horsetail, is completely hardy. It is therefore not necessary to overwinter the plant. You only have to ensure a frost-free winter if you grow winter horsetail in a pot.
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Do you have to overwinter winter horsetail?
Winter horsetail is hardy and does not require overwintering outdoors or on a pond. Only plants grown in pots should overwinter frost-free. Pruning is done in spring because the roots are deep and protected.
You don't have to overwinter horsetail
Winter horsetail is very robust. Frosty temperatures do not affect the plant. The roots are so deep in the earth that it would take weeks of severe frost to cause the roots to freeze.
You do not have to overwinter winter horsetail in the open field or by the pond. Don't cut it down in autumn either, but wait until spring to prune.
If the winter horsetail is grown in a bucket, you must overwinter it frost-free in the pot, just like the pond horsetail.
Tip
Like all horsetail species, winter horsetail tends to spread uncontrollably via runners. It is therefore better to plant the decorative plant in a pot.