HARDINESS: Zones 3 to 9
PREFERRED SOIL pH: Slightly acidic
PREFERRED SOIL TYPE: Average
PREFERRED LIGHT: Sun
ATTRIBUTES: Masses of orange flowers on compact, drought-tolerant plants; for beds
SEASON OF INTEREST: Summer
FAVORITES: The species, Asclepias tuberosa
QUIRKS: Late to emerge in spring and difficult to transplant
GOOD NEIGHBORS: Aster, ornamental grasses, rudbeckia, sneezeweed, stonecrop
WHERE IT GROWS BEST: Sun and average soil
POTENTIAL PROBLEMS: Butterfly larvae, occasional aphids
RENEWING PLANTS: Plants live for decades; seldom needs dividing
CRITTER RESISTANCE: Good
SOURCE: Seeds, rooted cuttings
DIMENSIONS: To 30 in (76.2 cm) tall, 18 in (45.7 cm) wide
Butterfly Weed in the Landscape
If your yard includes an area that's as hot and dry as a highway median strip, light it up with butterfly weed. This durable native plant is a little slow to get started, but once established it will thrive on neglect. It's a handsome, compact plant that blazes gloriously for many weeks in midsummer when it displays a crown of waxy, bright orange flowers.
The Orange Flowers Are a Butterfly Magnet.
Easily seen from afar but also interesting up close, butterfly weed's dense flower clusters comprise many small flowers, each with a yellow center and back-flung petals. Despite wilting heat, the flowers stand firm on 2 ft (0.6 m) tall rigid stems framed by leathery drought-resistant foliage. In late summer you will have to choose between coaxing the plant to produce a second flush of bloom by cutting off the old flowers or letting them ripen into ornamental seedpods.
Use masses of butterfly weed in sunny wildflower borders and on sunny slopes that are too rugged for other plants to thrive. In the warm-summer climates of Zones 7 to 9, butterfly weed does fine in full sun, but it can also be grown in partial shade.
Other Shades of Butterfly Weed
In the wild, butterfly weed flowers are always bright tangerine, though variations that shift toward yellow or red hues are not uncommon. For a white-flowered version, try Asclepias incarnata Tee Ballet', which stands substantially taller, at 40 in (101.6 cm). Other cultivated selections of A. incarnata sold by native plant nurseries typically have pink flowers, and are often called pink swamp milkweed. Unfortunately, aphids love this species much more than the orange butterfly weed, making it somewhat less care-free.
A Bevy of Butterflies
Monarch caterpillars and several other species feed on butterfly weed foliage. You can pick the caterpillars off, but try to relocate them to plants that are out of sight so that the caterpillars can mature into majestic orange-and -black butterflies. If you intend to let some plants serve as butterfly nurseries, locate them behind other flowers where the tattered foliage will not show in summer. Many other butterfly species also visit the plant to sip the blossoms' sweet nectar.
Growing Butterfly Weed
To get butterfly weed off to a strong start, set out container-grown plants in spring. Refrain from digging plants when they are actively growing, because the risk of breaking the brittle taproot and losing the plant is high.
A kinder way to propagate plants is to take 4 in (10.2 cm) stem cuttings in spring, strip off leaves from the lower half of the stem, and insert them half their length into a mixture of damp sand and peat moss. Keep the soil around cuttings moist and shade them until they are well rooted; then plant them in the garden.
Give new plants occasional water if a serious drought strikes the first summer after planting, and keep weeds pulled away from the growing points, or crowns. By their third summer, the plants should have thick tuberous roots and be able to fend for themselves in any type of weather.
Except for butterfly larvae (caterpillars), which eat leaves, pests are few. Bright yellow aphids sometimes appear in large numbers on new growth. You can simply rinse them off with water from a hose, pick off and dispose of infested leaves, or apply insecticidal soap per label directions.