Swamp Milkweed
Asclepias incarnata
- Native to:
- Canada, Mexico, Prince Edward I., United States, Virgin Islands
Photo by and (c)2007 Derek Ramsey ( Ram-Man (en.wikipedia.org) )
Taxonomy
- Division:
- Magnoliophyta | - Flowering plants
- Family:
- Apocynaceae
- Genus:
- Asclepias
- Species:
- Asclepias incarnata
- USDA Symbol:
- ASIN
Growth Characteristics
- Life Cycle:
- Perennial
- Growth Habit:
- Forb/herb
- Height:
- 150 cm
- Light Requirements:
- Full Sun,Part Shade
- Drought Tolerance:
- Low
- Bloom Months:
- jun,jul,aug
- Bloom Colors:
- pink, white
Wildlife Benefits
- Bees:
- ★★☆☆☆ Documented bee visitation (GBIF)
- Butterflies & Moths:
- ★★★★☆ Documented Lepidoptera association (GBIF)
- Caterpillars:
- ★☆☆☆☆ Recorded caterpillar host plant (HOSTS Database)
- Hummingbirds:
- ★☆☆☆☆ Documented hummingbird visits (GBIF)
Keystone Species Ranking
- Caterpillar Keystone:
- ★★☆☆☆ Butterfly & moth species supported by this genus (NWF)
Host Plant for Caterpillars
Delicate Cycnia (Cycnia tenera), Striped Garden Caterpillar Moth (Trichordestra legitima), ⚠️Monarch butterfly (Danaus plexippus), Queen butterfly (Danaus gilippus)
Reported Fauna Sightings
Bees: Black and gold bumble bee (Bombus auricomus), Brown-belted bumble (Bombus griseocollis), Common eastern (Bombus impatiens), Eastern Carpenter Bee (Xylocopa virginica), 🛑Rusty-patched bumble bee (Bombus affinis), Two-spotted bumble (Bombus bimaculatus), ⚠️Western honey bee (Apis mellifera), Zadontomerus Ashmead Hummingbirds: Ruby-throated Hummingbird (Archilochus colubris) Moths:Atteva aurea, Cycnia collaris, Eichlinia cucurbitae, Fall webworm (Hyphantria cunea), Grapeleaf skeletonizer (Harrisina americana), Hummingbird Clearwing (Hemaris thysbe), Milkweed Tussock Moth (Euchaetes egle), Snowberry Clearwing (Hemaris diffinis), Yellow-collared Scape Moth (Cisseps fulvicollis) Butterflies:American Lady (Vanessa virginiensis), Appalachian Eyed Brown (Lethe appalachia), Atalopedes Scudder, Banded Hairstreak (Satyrium calanus), Black Dash (Euphyes conspicua), Black Swallowtail (Papilio polyxenes), Broad-winged Skipper (Poanes viator), Cabbage White (Pieris rapae), Clouded Sulphur (Colias philodice), Common Buckeye (Junonia coenia), Common Wood-Nymph (Cercyonis pegala), Delaware Skipper (Anatrytone logan), Dion Skipper (Euphyes dion), Dun Skipper (Euphyes vestris), Eastern Giant (Heraclides cresphontes), Eastern Tailed-Blue (Cupido comyntas), Eastern Tiger Swallowtail (Pterourus glaucus), Eastern Tiger Swallowtail (Papilio glaucus), Field Skipper (Atalopedes campestris), Fiery Skipper (Hylephila phyleus), Gray Hairstreak (Strymon melinus), Great Spangled (Argynnis cybele), Julia butterfly (Dione vanillae), Least Skipper (Ancyloxypha numitor), Little Glassywing (Vernia verna), Mulberry Wing (Poanes massasoit), Northern Broken-Dash (Polites egeremet), Orange Sulphur (Colias eurytheme), Painted Lady (Vanessa cardui), Palamedes Swallowtail (Papilio palamedes), Pearl Crescent (Phyciodes tharos), Peck's skipper (Polites peckius), Pipevine Swallowtail (Battus philenor), Queen butterfly (Danaus gilippus), Red Admiral (Vanessa atalanta), Red-banded Hairstreak (Calycopis cecrops), Red-Spotted Purple (astyanax) (Limenitis arthemis), Silver-spotted Skipper (Epargyreus clarus), Silvery Checkerspot (Chlosyne nycteis), Spicebush Swallowtail (Pterourus troilus), Spicebush Swallowtail (Papilio troilus), Summer Azure (Celastrina neglecta), Tawny-edged Skipper (Polites themistocles), Variegated Fritillary (Euptoieta claudia), Viceroy (Limenitis archippus), Western Tiger Swallowtail (Papilio rutulus), Wild Indigo Duskywing (Gesta Evans), Zabulon Skipper (Poanes zabulon), Zabulon Skipper (Lon zabulon), Zebra Swallowtail (Eurytides marcellus)
Garden & Ecology Notes
- Wildlife Value:
- butterflies, bees, hummingbirds
- Fragrant:
- Yes
Soil Requirements
- Soil Type:
- moist, rich, well-drained loamy soil
- pH:
- 5.5 - 7.0 (slightly acidic to neutral)
- Drainage:
- tolerates poor drainage
- Moisture:
- consistently moist
- Notes:
- prefers wetland areas and stream banks
Propagation & Germination
- Stratification:
- Cold/moist stratification required — 30–60 days
- Germination Time:
- 14–30 days
- Notes:
- Seeds benefit from cold stratification for 30-60 days to break dormancy; sow in spring after last frost.
Pre-treatment: Seeds require one week of moist cold stratification or can be placed in fine mesh bags into a 1% hydrogen peroxide (3:1 water/3% hydrogen peroxide) soak for 24 hours, rinsed, and placed in water for an additional 24 hours. The bags are then placed in sealed containers in refrigeration at 1 to 3 °C for 45 days. Check seeds weekly for mold and treat with 1% hydrogen peroxide if needed.
Establishment: Seeds are collected in the fall, when the brown pods are dry and have begun to split. Swamp milkweed is widely distributed across the U.S. and Canada. It is found in a variety of soil types, inhabiting wet places but also grows well in fields, roadsides, waste places and dry sites.
Source: npn.rngr.net
ORGHPS Germination Guide: Sow @ 20°C. Seed germinates within 3 months Resents transplanting. Requires light or the seed is very fine. Surface sow and expose to light. * plant in deep pot or in situ to avoid damaging long taproot; seed viability < 1 year
Where to Buy
Nationwide Seller
- Vermont Wildflower Farm (nursery and seeds)
- Sheffield's Seed (seeds)
- Wild Seed Project (seeds)
- Native Plants Nursery (nursery)
- Native Plants Nursery (nursery)
- Pizzo Native Plant Nursery (wholesale nursery)
- Prairie Moon Nursery (nursery and seeds)
- Ernst Seeds (seeds)
- Ernst Seeds (seeds)
- Ernst Seeds (seeds)
- North Creek Nurseries (nursery)
- Native American Seed (nursery and seeds)