Author Teresa Odle 7-6-2020
Butterfly bushes can grow well in containers, provided the right potting mix and container location. Several dwarf varieties, like the Lo and Behold and Pugster series, are especially sized for container growing since they are slightly more or less than 2 feet high and wide each summer. Placing the container where it receives at least 6 hours of sun a day, preferably 8 hours, ensures the best flowering. Then, check some of the tips below for soil and watering of butterfly bushes grown in containers vs. those grown in the ground.
Planting Butterfly Bush in Pots
To grow a butterfly bush in a pot, it is best to plant the bush in spring, after danger of frost has passed and before peak summer heat. It's possible to plant them in fall, but containers cool more than the ground, so using a pot for a butterfly bush at the colder end of their hardiness zone (usually about zone 5) can cause freeze damage if the roots have not had time to grow. Choose full sun year-round if possible. Be sure the container chosen will hold the shrub, so the diameter should be a little larger and twice as tall as the root ball/container of the plant purchased. The container should have plenty of drainage holes and be weatherproof for outdoors.
Best Soil For Butterfly Bushes in Pots
The best potting mix will drain well and be lightweight. Adding a little organic compost also helps with drainage. There is no need to mulch the top of the container soil.
Caring For Butterfly Bushes in Planters
Potting mix usually is packed with nutrients, so the butterfly bush should need no fertilizing or soil amendment in the first year. After the soil begins to thaw in spring, add a balanced granular fertilizer to the container soil, then gently mix or trowel it in, and water. Containers can get hotter in summer and cooler in winter than the ground, so that is good to keep in mind for placement. It is possible to move most pots to maximize sun exposure. Deadhead spent flowers to encourage more blooms and prune the butterfly bush to new growth just above the base in spring.
Watering Butterfly Bush in Pots
Butterfly bushes do not like having soggy roots, so over-watering can damage the shrub. Despite that, the low-water user needs more frequent watering when growing in a container than in the ground. Containers tend to dry out quickly. It is best to water slowly and deeply, such as with a container drip system. Avoid watering after rain, but water the shrub—especially a new one—a little extra during peak drought and heat.
Fertilizing Butterfly Bush in Pots
Normally, butterfly bushes need no fertilizing, but they can benefit from yearly balanced feeding when grown in containers. Avoid a high nitrogen fertilizer, which can cause the shrub to grow so quickly that the stems are weak.
Winter Care For Butterfly Bushes in Pots
If a butterfly bush is in a weatherproof container, it can stay outside in winter. In colder climates at the edge of a variety's growing zone, it is best to leave the container where it gets some winter sun. Leave the stems on a butterfly bush after leaves drop. This protects it better in winter than if it is pruned in fall. For a container that will last long, choose a high-end glazed ceramic container.
Can Butterfly Bush Be Grown Indoors
A butterfly bush needs no winter watering but will manage with some snow or other natural moisture. The plants need to stay outside for all or most of winter, so it is best to choose a butterfly bush that matches the cold hardiness of your zone. The container can live inside a garage for a short time, especially if the garage gets bright light in winter.