Milkweed is among the primary plants to draw the Monarch butterfly to our yards. We all love to see them flitting through the summer flowers in our beds, so we want plants to attract them and encourage them to return. Since milkweed is sometimes considered an unwanted specimen in the landscape and can be invasive, we might consider growing milkweed in a pot.
Container Grown Milkweed Plants
There are more than 100 species of milkweeds that grow in North America, and not all of them are hosts for the Monarch. Some draw Monarchs for nectar, but butterfly lovers are likely looking for those plants that encourage the dropping of tiny eggs on them. Let’s take a look at some that are native or naturalized plants and that can grow successfully in a container.
- Tropical milkweed (Asclepias curassavica) – This has naturalized in warmer areas of the U.S. and is a favorite of the Monarch butterfly. It also provides nectar for them and many other types of butterflies. Those in cooler areas may grow this as an annual plant, and it may return in protected areas, or reseed. Container grown plants sport additional branches in their second year and a long bloom period in summer.
- Whorled milkweed (Asclepias verticillata) – A larval host plant that grows in dry or sandy soils, this whorled milkweed is hardy in USDA zones 4a to 10b. This North American native blooms summer through fall and provides food for caterpillars as well as adult Monarchs and is a great milkweed in planters.
- Swamp milkweed (Asclepias incarnata) – This plant is “known to be high up in the Monarchs preference list.” Native to most of the U.S., you’ll want to include this one if you’re attempting to draw butterflies to a wet area. This specimen does not have a taproot, another advantage for container growing.
- Showy milkweed (Asclepias speciosa) – Flowers are fragrant and pretty. Best confined to a pot because of its invasive tendency. Grows in western U.S. to Canada and is equivalent to common milkweed in the east. Showy milkweed needs a five gallon (19 L.) or larger container.
How to Grow Milkweed in a Pot
Growing milkweed in containers is the preferable method of growth for some. Container-grown milkweed can be overwintered in a building or garage and placed back outside in spring.
Info suggests combining potted milkweeds with nectar-rich flowers in the same container to provide necessary nourishment to the Monarch and other butterflies. This encourages them to return to the area where containers are, so locate them near a seating area where you can best enjoy them.
Use a large plastic container for ease of moving and winter storage. Use a light-colored one that is deep, as root systems of milkweed plants can grow large. Some have large taproots. A rich and well-draining soil encourages the best performance of the plants. You can start them from seed, for a cost-effective project.