Height: 24-36 in. (60-90 cm) 36-48 in. (90-120 cm)
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) USDA Zone 9a: to -6.6 °C (20 °F) USDA Zone 9b: to -3.8 °C (25 °F)
Sun Exposure: Full Sun Sun to Partial Shade
Danger: All parts of plant are poisonous if ingested
Bloom Color: White/Near White
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: 5.1 to 5.5 (strongly acidic) 5.6 to 6.0 (acidic) 6.1 to 6.5 (mildly acidic) 6.6 to 7.5 (neutral)
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: Allow seedheads to dry on plants; remove and collect seeds Properly cleaned, seed can be successfully stored
On Jun 4, 2010, mountaindog from Phoenicia, NY (Zone 5a) wrote:
This is a really beautiful white-flowering NY-native plant that I used to replace some more invasive exotic white-flowering plants. It is a handsome-foliaged, clump-forming plant that blooms late-July until end of summer when a lot of other flowers are done. Looks great planted next to native blue garden phlox. Butterflies do indeed love it, no issues with aphids so far. Does great in my zone 5a garden in full-sun with a good layer of mulch.
On Jul 4, 2006, Joan from Belfield, ND (Zone 4a) wrote:
Milkweed is essential food for the monarch butterfly larva. I have one little struggling plant in a part of the yard that's not taken care of the best, but today I snapped some photos and on this struggling little plant, there were 8 monarch larva feeding. I'm gonna start taking better care of that plant.
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.
I have read that it is hardy in zones 3-9.
Blooms late June to mid July in my garden.
This plant has been said to grow in the following regions:
, North Little Rock, Arkansas Hollywood, Florida Cordele, Georgia Edwardsville, Illinois Evanston, Illinois Machesney Park, Illinois Mount Prospect, Illinois Barbourville, Kentucky Hebron, Kentucky Brookeville, Maryland Spencer, Massachusetts Bellaire, Michigan Dearborn Heights, Michigan Pinconning, Michigan Redford, Michigan Andover, Minnesota Warsaw, Missouri Glen Head, New York Phoenicia, New York Belfield, North Dakota North River, North Dakota East Lansdowne, Pennsylvania East Norriton, Pennsylvania Wilkes-barre, Pennsylvania Austin, Texas Eagle Mountain, Texas Arlington, Virginia Leesburg, Virginia Lexington, Virginia Eastgate, Washington Kalama, Washington Hartford, Wisconsin