Height: 24-36 in. (60-90 cm) 36-48 in. (90-120 cm) 4-6 ft. (1.2-1.8 m)
Spacing: 24-36 in. (60-90 cm)
Hardiness: USDA Zone 3a: to -39.9 °C (-40 °F) USDA Zone 3b: to -37.2 °C (-35 °F) USDA Zone 4a: to -34.4 °C (-30 °F) USDA Zone 4b: to -31.6 °C (-25 °F) USDA Zone 5a: to -28.8 °C (-20 °F) USDA Zone 5b: to -26.1 °C (-15 °F) USDA Zone 6a: to -23.3 °C (-10 °F) USDA Zone 6b: to -20.5 °C (-5 °F) USDA Zone 7a: to -17.7 °C (0 °F) USDA Zone 7b: to -14.9 °C (5 °F) USDA Zone 8a: to -12.2 °C (10 °F) USDA Zone 8b: to -9.4 °C (15 °F)
Sun Exposure: Sun to Partial Shade
Danger: All parts of plant are poisonous if ingested
Bloom Color: Pink Purple
Bloom Time: Mid Summer Late Summer/Early Fall
Other details: This plant is attractive to bees, butterflies and/or birds Requires consistently moist soil; do not let dry out between waterings
Soil pH requirements: 5.6 to 6.0 (acidic) 6.1 to 6.5 (mildly acidic) 6.6 to 7.5 (neutral)
Patent Information: Non-patented
Propagation Methods: By dividing rhizomes, tubers, corms or bulbs (including offsets) From seed; direct sow outdoors in fall From seed; winter sow in vented containers, coldframe or unheated greenhouse From seed; stratify if sowing indoors
Seed Collecting: Bag seedheads to capture ripening seed Allow pods to dry on plant; break open to collect seeds Properly cleaned, seed can be successfully stored
On Jun 15, 2013, Chillybean from Near Central, IA (Zone 4a) wrote:
We bought some plugs last spring, along with a couple of other natives. They were decimated by Oleander Aphids last year, but have bounced back quite nicely this spring. Even with last year's drought. The other natives did not fair quite so well; there's no sign of them.
We just added some of these to our sunny garden in Westwood, NJ, (bought them on eBay in July because I couldn't find a local nursery that sells them) and it's Labor Day weekend, and we already have a Monarch caterpillar; this seems late in the season to me, but we certainly are enjoying our good luck! Also have some beautiful pink blooms.
On Sep 5, 2011, mom4monarchs from Dover, DE wrote:
I have found swamp milkweed to be the easiest to grow of the milkweed varieties I've tried. The monarchs love it (and they desperately need our help). The only problem is that by August the leaves turn yellow and then drop on some plants. (Any advice would be appreciated). One tip for propagation is to cut off a stem, remove the leaves, cut it into 6 inch pieces and and put the pieces into pots. New leaves will appear within a few weeks - much faster than seeds.
On Feb 21, 2011, pirateradio from Waynesboro, PA wrote:
Swamp milkweed is native to my property. Last year, I collected seeds & this year, I've started seedlings inside to bolster the yard against some of the nasty invasives (Canada thistle, exotic honeysuckles, etc.) that also are growing here.
On Aug 14, 2009, SusanLouise from Lincoln, NE (Zone 5b) wrote:
Our milkweed reached a height of over 5'. One of the 2 pics I submitted shows it's height and width of just 2 plants that are just 2 years old...incredable!!!
Since I don't need anymore milkweed of this variety, I do harvest all the pods before they open since I don't want them to multiply in our garden/yard. This is one plant, due to it's size, that I don't want it to self sow...even accidentally!
On Jan 17, 2006, Breezymeadow from Culpeper, VA (Zone 7a) wrote:
This plant is native to at least the Piedmont area of Virginia, & I am lucky to have a couple of clumps growing wild in a couple of semi-shady spots on my property. Since they are growing in areas that do get mowed at least once a year, when my perennial gardens are finally established, I will probably relocate these lovely clumps to safety.
The pink flower clusters are pretty, with a subtle sweet fragrance. As others have stated, they're very attractive to butterflies.
Swamp Milkweed blooms are very pretty, but it is extremely susceptible to aphids. I plant mine in the back of my yard where it is there for butterflies, but the aphid-attacked plants won't be in full view.
On Feb 11, 2005, ACHunter47 from Elmore, AL (Zone 8a) wrote:
I have grown Milkweed for two years. The Monarch caterpillars eat all of the leaves off of the plant. So, don't kill the caterpillars. My plants came back last year and bloomed again after the leaves were eaten. I had a couple of the caterpillars build their chrysalis on the side of my greenhouse. I took pictures of them at certain stages. It was very interesting and exciting to watch them develop into butterflys and fly away.
On Oct 23, 2004, SalmonMe from Springboro, OH (Zone 6a) wrote:
Worthy to note that not only do Monarchs LIKE Asclepias, but Asclepias plants are the ONLY kind of plant that the larvae/caterpillars can survive on. The caterpillars do not eat any other host plant. It helps, too, that the plants are truly lovely.
On Aug 31, 2003, suncatcheracres from Old Town, FL wrote:
I'm always happy to find a new plant for Monarchs, which are threatened in the wild. This entry gave me the interest to look this plant up in some books, and I found out it really likes wet conditions, which I have in Northcentral Florida, zone 8b, so I'll look for some seed to start plants next Spring. I'm at the bottom end of its range, but I'll try hard to find the right niche for it.
The pretty pink color should go nicely with my pink Brugmansias, and pink azaleas, and pink cannas and pink tiger lilies. Obviously I'm developing a pink bed, with a little cream and paler yellows thrown in for variety. This bed has a mixture of sun and shade, so I'll find a place for this pretty and useful plant. I read it grows three to five feet tall, so it would make a nice background plant.
One of my books said there is also a more compact white variety of swamp milkweed called 'Ice Ballet'--to three and a half feet tall. That book also noted that swamp milkweed is a native plant to the US, unlike the scarlet milkweed, A. curassavica, which is from South America--scarlet milkweed is now happily growing all over my garden this summer. However, Monarchs will come to all milkweeds, the adults for flower nectar, and to the whole plant as fodder for their caterpillars.
Monarch habitat is diminishing, so any type of milkweed that will grow in your garden should be encouraged. I've tried to grow A. tuberosa, which likes drier conditions, but wasn't very successful. I'll probably try again in a raised bed for better drainage, with lots of sun, as it is also a native US milkweed with very bright flowers. 'Gay Butterflies' is yellow and red, and 'Hello Yellow' is of course bright yellow. For Western US gardens there is a California native with subtle white and cream flowers. Apparently there are lots of different kinds of Asclepias, so there should be one suitable for just about every garden where the Monarchs fly.
On Aug 12, 2001, poppysue from Westbrook, ME (Zone 5a) wrote:
This member of the milkweed family is a well-behaved garden plant. It forms a large clump and will not spread by runners like so many of its cousins. The flowers clusters are 2-4 inches across and have a nice fragrance. It prefers full sun and loves wet soils but it will also grow well in average garden soil.
It's a wonderful addition to a butterfly garden. The adults sip nector from the flowers and monarch butterflies use it as a host plant. The female will lay her eggs on the plant and the young caterpillars feed on the foliage.
This plant has been said to grow in the following regions:
Elmore, Alabama North Little Rock, Arkansas Highlands Ranch, Colorado Kiowa, Colorado Rodney Village, Delaware Cheval, Florida Fruitville, Florida Gibsonton, Florida Loxahatchee, Florida Melrose Park, Florida Saint Cloud, Florida Demorest, Georgia Marietta, Georgia Cherry Valley, Illinois Crystal Lake, Illinois Divernon, Illinois Edwardsville, Illinois Itasca, Illinois Jerome, Illinois La Grange Park, Illinois Machesney Park, Illinois Mount Prospect, Illinois Thomasboro, Illinois Galena, Indiana Homecroft, Indiana Washington, Indiana Ames, Iowa Yale, Iowa Brookville, Kansas Derby, Kansas Hamlin, Kansas Barbourville, Kentucky Prospect, Kentucky Eden Isle, Louisiana Brookeville, Maryland Dundalk, Maryland Springfield, Massachusetts Allen Park, Michigan Barton City, Michigan Dearborn Heights, Michigan East Tawas, Michigan Breezy Point, Minnesota Fridley, Minnesota Kasota, Minnesota Minneapolis, Minnesota Onamia, Minnesota St Paul, Minnesota Young America, Minnesota University City, Missouri Helena, Montana Beatrice, Nebraska Lincoln, Nebraska , New Jersey Frenchtown, New Jersey Jersey City, New Jersey Old Tappan, New Jersey Ramblewood, New Jersey Elephant Butte, New Mexico Blossvale, New York Ogdensburg, New York Charlotte, North Carolina Hays, North Carolina Tobaccoville, North Carolina Bexley, Ohio Bowling Green, Ohio Dayton, Ohio Findlay, Ohio Florida, Ohio Fort Jennings, Ohio Glouster, Ohio Holiday Valley, Ohio Oak Harbor, Ohio Riverside, Ohio Saint Marys, Ohio Springboro, Ohio Garden Home-whitford, Oregon Ashley, Pennsylvania East Norriton, Pennsylvania Malvern, Pennsylvania Milford, Pennsylvania Philadelphia, Pennsylvania Wayne Heights, Pennsylvania Conway, South Carolina Parker, South Dakota Viola, Tennessee Bayview, Texas Watauga, Texas Salt Lake City, Utah Arlington, Virginia Leesburg, Virginia Manassas, Virginia Mc Lean, Virginia Newport News, Virginia Sterling, Virginia Bath, West Virginia Cabin Creek, West Virginia Liberty, West Virginia De Pere, Wisconsin Madison, Wisconsin Shorewood, Wisconsin