Showy milkweed provides two attractive components to your garden. First of all, it bears lovely rosy purple flowers. Secondly, it is also a great plant for attracting butterflies and hummingbirds. In autumn, the flowers are succeeded by striking seed pods up to three inches long.
The pods split open at maturity to reveal the seeds within. A cotton-like fluff is attached to the seeds, allowing them to be spread by the wind. When the stem of showy milkweed is broken, a milky sap runs out of it, accounting for the common name "milkweed." The leaves are large and up to 8 inches long, oval, bluish-green, and have prominent veins.
Showy milkweed resembles common milkweed, but it can be distinguished from the latter in two ways:
- Flowers: The star-shaped flowers are larger, and there is more space between the individual flowers in the flower head (or "umbel," which measures 3 inches across), making them stand out in a showy fashion
- By the presence of tiny fibers or "hairs" on the plant
Showy milkweed is perhaps most valued as being a host plant for the larvae (caterpillars) of monarch butterflies. Learn how to give showy milkweed the optimal conditions that it needs to put on a spectacular show in your landscape.
|Common Name||Showy milkweed|
|Botanical Name||Asclepias speciosa|
|Plant Type||Herbaceous, Perennial|
|Mature Size||1-3 feet tall|
|Soil pH||Acidic, Neutral, Alkaline|
|Bloom Time||Spring, Summer|
|Flower Color||Purple, Pink|
|Hardiness Zones||3-9 (USDA)|
|Native Area||North America|
|Toxicity||Toxic to cats, dogs, horses, and humans|
Showy Milkweed Care
Showy milkweed is easy to grow. It tolerates drought and poor soils. It may perform better in such ground than it does in soils that are wet and very fertile.
Since the plant will self-seed, some gardeners may find it a bit too easy to grow. There are better-behaved plants to grow in a mixed flower bed than showy milkweed; however, it does not spread as much as the common milkweed. To prevent the plant from spreading, simply cut off the seed pods before they open.
Once the plant becomes established, avoid trying to transplant it, since showy milkweed has a deep taproot. At planting time, select a spot for it in the landscape where you know you will want it to grow for several years.
Showy milkweed blooms best if given full sun.
The main soil requirement for showy milkweed is good drainage.
Do not overwater the plant once it is established. Showy milkweed prefers soil that is somewhat on the dry side.
There is no need to fertilize showy milkweed. Too much fertilizer may result in underperformance.
Varieties of Milkweed, Related Plants
Asclepias is only one of many genera that belong to the Apocynaceae family. Other members of the family include:
- Dogbane (Apocynum cannabium)
- Blue star (Amsonia tabernaemontana)
- Oleander (Nerium oleander)
- Rocktrumpet (Mandevilla x amabilis)
Even within the Asclepias genus, there are many other species. They come in different heights and colors.
- Common milkweed (Asclepias syriaca): 2 to 4 feet in height; pink-purple
- Butterfly weed (Asclepias tuberosa): 1 to 2 feet in height; light orange
- Swamp milkweed (Asclepias incarnate): 4 to 5 feet in height; mauve, pink, or white
- Sandhill milkweed (Asclepias humistrata): 1 to 3 feet in height; pink, lavender, or white
Should I plant showy milkweed or common milkweed in the garden?
Although showy milkweed resembles common milkweed, showy milkweed is the better choice for the home garden because it is significantly less aggressive than its invasive cousin.
When is the best time to cut back showy milkweed?
You can cut back the plant in fall or spring. After the first frost in late fall, cut the dead stalks to the ground, or wait until early spring so that small animals and birds can use the fibers around the seeds and from the stalks to build their nests.
What other animals are attracted to showy milkweed?
In addition to attracting Monarch butterflies and hummingbirds, Snowy Milkweed attracts bees, moths, and other birds and butterflies.
Showy Milkweed. USDA Natural Resources Conservation Service