Swamp Milkweed
Asclepias incarnata
- Native to:
- Canada, Mexico, Prince Edward I., United States
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,sep
- Bloom Colors:
- pink, rose, mauve, white
Wildlife Benefits
- Bees:
- ★☆☆☆☆ Documented bee visitation (GBIF)
- Butterflies & Moths:
- ★☆☆☆☆ Documented Lepidoptera association (GBIF)
- Caterpillars:
- ★☆☆☆☆ Recorded caterpillar host plant (HOSTS Database)
Keystone Species Ranking
- Caterpillar Keystone:
- ★★☆☆☆ Butterfly & moth species supported by this genus (NWF)
Host Plant for Caterpillars
Reported Fauna Sightings
Garden & Ecology Notes
- Wildlife Value:
- monarch butterflies, bees, hummingbirds, other butterflies
- Deer Resistant:
- Yes
- Fragrant:
- Yes
- Fall Color:
- yellow
- Fire Ecology:
- Fire adapted — tolerates or benefits from fire
- Fire Notes:
- Resprouts vigorously from rhizomes after fire or mowing. Benefits from periodic disturbance that reduces woody competition in wetland habitats.
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:
- 7–21 days
- Notes:
- Seeds require light for germination; surface sow or barely cover. Cold stratification improves germination rate and uniformity.
The above propagation data sourced from Claude AI
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