Anemones are at home in the Near East and southern Europe. Most varieties cannot tolerate subzero temperatures. The information about the winter hardiness of anemones is sometimes quite contradictory. However, you can assume that most perennials are hardy, but most tubers are not.
Are anemones hardy?
Anemone perennials are generally hardy, especially older plants. However, in the first year they often need winter protection such as leaves or straw. Anemone tubers, especially noble varieties such as Anemone coronaria, are considered less hardy and should be kept frost-free over the winter.
Anemone perennials are usually hardy
Autumn anemones sometimes grow in the same place for many years. Older plants are absolutely winter-hardy and can tolerate sub-zero temperatures.
In the first year after planting, the anemones are not that robust. It's better to provide them with some winter protection. This also applies to perennials that you have already planted at the best planting time in spring. The following are well suited as covering material:
- Dry leaves
- Straw
- Tree cutting
- Do not use softwoods
Never cover the anemones with pine branches. The falling needles acidify the soil too much.
Anemones from tubers are rarely hardy
Anemones that bloom in spring are in most cases grown from tubers. The package often states that the onions are hardy.
You shouldn't rely on that. At very low temperatures the tubers freeze. This is especially true for the noble varieties of anemones, the Anemone coronaria. Your tubers must always be kept frost-free over the winter.
Always plant anemones from tubers in early spring. They then bloom a little later, but don't suffer from the cold.
Overwinter anemone bulbs frost-free
You should pull the anemone bulbs out of the ground in the fall just like those of gladioli. Let them dry, remove the remaining soil and overwinter in a dry, dark place without risk of frost.
If your garden and especially the location of your anemones is very protected, it may be sufficient to protect the planting sites of the tuberous anemones from frost with a thick cover of foliage.
Remove the mulch in early spring to allow the first rays of sunlight to warm the soil and encourage the tubers to sprout.
Tips & Tricks
If you don't know whether your anemones are hardy, to be on the safe side, you should dig them up in the fall and overwinter them indoors. Test the winter hardiness by leaving some of the tubers or perennials in the garden and see whether they sprout again next year.