Hostas are hardy perennials that grow best in USDA zones 3 through 9. Hostas actually enjoy the winter cold, because this brings on their much-needed dormancy period. Little care is required for hosta plants during the winter, but there are some steps of precaution you must take if your hostas are either container-grown, or are small or dwarf hostas planted in the ground.
Winter Care for Outdoor Container-Grown Hostas
Remove all dead leaves. The soil surface can freeze, but don’t let the entire container freeze solid. Planter pots that are less than two feet in diameter will likely freeze solid.
Cover the soil surface with a three-inch layer of organic mulch or wood chips after the soil surface has frozen. Lay evergreen boughs on top of the mulch for added insulation and to keep the mulch from blowing away.
Wrap the container in a blanket or other insulating material if the container is small. Move the hosta plants to a spot that is protected from the wind.
Winter Care for Hostas in the Ground
Rake away all of the previous season’s decayed leaves in late February or early March. Don’t disturb the foliage until this time. This is all you’ll need to do to care for a large hosta plant in the winter.
Spread a two- to three-inch layer of organic compost, mulch or peat moss around the small or dwarf hostas, only after the ground freezes. This will help to protect the hostas’ root systems from becoming exposed to the elements when the hostas heave during a freeze/thaw cycle.
Rake away the compost, mulch or peat moss gently in mid- or late March. Wait until the last expected freeze or for when the leaves begin to grow to remove it.