What is it? Asclepias incarnata, commonly known as the swamp milkweed, is a herbaceous perennial plant.
Native to where? It is native to North America.
Hardiness Zone: Plants are hardy from USDA Hardiness Zones 3 to 6.
What does it look like? Swamp milkweed plants usually grow about 3 to 4 feet tall, producing small, fragrant, pink to mauve (sometimes white) colored flowers in rounded umbellate groups of blossoms.
Bloom Time: The plants bloom in early to mid-summer with rose shades from pinks to purples.
Growth Habit: It does not spread aggressively like some other milkweeds. It grows from thick, fleshy, white roots. Typically, its stems are branched and the clump-forming plants emerge in late spring after most other plants have begun growth for the year. After blooming, green follicles, approximately 12 cm (4+3⁄4 in) long, are produced that when ripe, split open. They then release light or dark brown flat seeds that are attached to silver-white, silky hairs which catch the wind. Although Asclepias incarnata plants can survive for up to 20 years, most live only two-five years in gardens. The species is not shade-tolerant and is not a good vegetative competitor.
Growing Conditions: Asclepias incarnata prefer moist locations, will also grow well in medium moisture once they are established, even doing well in wet clay soils and poorly drained soils.
Environmental Benefits: Host plant to Monarch and Queen butterflies, nectar to many.
Sources:
https://www.joyfulbutterfly.com/product/swamp-milkweed-plants/
https://en.wikipedia.org/wiki/Asclepias_incarnata
Image Sources:
By Teune at the English-language Wikipedia, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=4796425
By Photo by and (c)2009 Derek Ramsey (Ram-Man) - Self-photographed, GFDL 1.2, https://commons.wikimedia.org/w/index.php?curid=7141778