Walton's Plant Library

Other Names:  Giant Milkweed, Swallow Wort

Description:

Stunning crown shaped flowers of lavender and white, atop attractive, large oval foliage; blooms all season; becomes a large shrub with woody stems in frost free areas; attracts Monarch butterflies and pollinators; perfect for borders or containers

Ornamental Features

Crown Flower (Giant Milkweed) features showy clusters of lightly-scented lavender star-shaped flowers with white overtones at the ends of the branches from early spring to late fall. The flowers are excellent for cutting. Its oval leaves remain green in color with curious gray undersides throughout the season.

Landscape Attributes

Crown Flower (Giant Milkweed) is a multi-stemmed annual with an upright spreading habit of growth. Its medium texture blends into the garden, but can always be balanced by a couple of finer or coarser plants for an effective composition.

This is a relatively low maintenance plant, and is best cleaned up in early spring before it resumes active growth for the season. It is a good choice for attracting bees and butterflies to your yard, but is not particularly attractive to deer who tend to leave it alone in favor of tastier treats. It has no significant negative characteristics.

Crown Flower (Giant Milkweed) is recommended for the following landscape applications;

• Mass Planting
• General Garden Use
• Container Planting

Planting & Growing

Crown Flower (Giant Milkweed) will grow to be about 10 feet tall at maturity, with a spread of 6 feet. It has a low canopy with a typical clearance of 1 foot from the ground. Although it's not a true annual, this fast-growing plant can be expected to behave as an annual in our climate if left outdoors over the winter, usually needing replacement the following year. As such, gardeners should take into consideration that it will perform differently than it would in its native habitat.

This plant should only be grown in full sunlight. It prefers to grow in average to moist conditions, and shouldn't be allowed to dry out. It may require supplemental watering during periods of drought or extended heat. It is not particular as to soil type or pH. It is highly tolerant of urban pollution and will even thrive in inner city environments. Consider applying a thick mulch around the root zone in winter to protect it in exposed locations or colder microclimates. This species is not originally from North America, and parts of it are known to be toxic to humans and animals, so care should be exercised in planting it around children and pets.

Crown Flower (Giant Milkweed) is a fine choice for the garden, but it is also a good selection for planting in outdoor pots and containers. Its large size and upright habit of growth lend it for use as a solitary accent, or in a composition surrounded by smaller plants around the base and those that spill over the edges. It is even sizeable enough that it can be grown alone in a suitable container. Note that when growing plants in outdoor containers and baskets, they may require more frequent waterings than they would in the yard or garden.