Author Teresa Odle 7-6-2020
Butterfly bush is a hardy perennial in many areas of the country. Generally, the shrub can take winter cold down to zone 5 (-15 to -20 degrees) and thrives in heat up to zone 9. Still, the plant loses its leaves and goes dormant in winter to weather the cold. There are some steps you can take to prepare your butterfly bush for its winter rest.
If nighttime temperatures are predicted to fall below -20 degrees, you can protect the shrub by covering it with a light blanket and removing the blanket as soon as the temperature warms. Snow typically will not damage butterfly bushes. The bush blooms on new wood, so if one of the branches breaks, just make a clean cut where it breaks.
Cutting Back Butterfly Bush For Winter
Most butterfly bushes lose their leaves in late fall, and the roots remain viable underground while the plant winters over. That means in most growing zones, there is no need to prune your butterfly bush before winter. In fact, pruning too late in fall could leave it more susceptible to damage. Leave the bare stems through winter if you can, letting birds enjoy landing on them near your winter bird feeder. Those who live in the warmest zones can prune their butterfly bushes sooner if they prefer not to have the care stems in the landscape.
Butterfly Bush Winter Care in Pots
If you grow butterfly bush in a container, be aware that temperatures are colder around the roots in that container than in the ground. So, add 5 to 10 degrees to the lowest winter temperature your variety can take and move the plant into a garage or other protected location. You also can move the container to a warmer spot, such as against a south-facing wall, or insulate the outside of the container.
Watering Butterfly Bush in Winter
Begin to cut back on watering in fall; the plant does not like to sit in soggy and cool soil, which can cause root rot. If no snow or other winter precipitation falls for a month or so, water the plant slowly and deeply in the morning on a sunny winter day. There is no need to water more often until new growth appears in spring.
Growing Butterfly Bush Indoors
To overwinter a butterfly bush in areas colder than zone 5, dig the shrub up from the ground in late summer or early fall and place it in a container with potting mix. Water it regularly during its transition to the pot and cut back on watering gradually until before the first frost. Water it no more than about monthly in winter so it can go into a period of dormancy.
Steps To Care For Butterfly Bush in Winter
Caring for a butterfly bush in winter is simple for anyone living in its normal growing zones (5 through 9). Here are a few steps to take for butterfly bushes in the winter.
Step 1. Don't plant a new butterfly bush in fall; the shrub needs time to establish before winter dormancy.
Step 2. Unless you live in a warm zone with few winter freezes, avoid pruning butterfly bush in fall or winter.
Step 3. Water sparingly beginning a few weeks before expected frost to avoid root rot.
Step 4. Let butterfly bush go dormant in winter.
Step 5. Avoid pruning until new growth begins to appear at the base of the plant.