Asclepias incarnata (Swamp Milkweed)

Native perennial • Monarch host plant • Wet-loving milkweed

Asclepias incarnata is a moisture-loving native milkweed with fragrant pink blooms that draw monarchs, swallowtails, and dozens of native pollinators. Essential habitat plant in ecological gardens, wetlands, and rain gardens.

 Light

• Full sun
  
  

• Tolerates part sun, but best in open sites
  
  

• 6–8 hours optimal
  
  

More sun = more bloom + stronger stems.

 Water

• Likes moisture best of all milkweeds
  
  

• Ideal for wet soils, rain gardens, pond edges
  
  

• Tolerates average garden soil once established
  
  

• Do not allow to fully dry during establishment
  
  

One of the few native perennials that thrives in wet sites.

 Soil

• Clay, loam, silty, or organic-rich soils
  
  

• Performs great in heavy, wet clay
  
  

• Avoid very dry, sandy soils unless irrigated
  
  

Hardiness

• USDA Zones 3–9
  
  

• Heat and humidity tolerant
  
  

• Excellent Southeastern native
  
  

Blooming

• Mid-summer through late summer
  
  

• Fragrant flowers
  
  

• Supports:
  
  

  • monarch caterpillars (host plant)
    
    

  • monarch adults (nectar)
    
    

  • native bees
    
    

  • swallowtails
    
    

  • beetle pollinators
    
    

  • beneficial insects
    
    

High ecological value.

 Monarch Host Plant

Caterpillars feed on the leaves.
Adults feed on nectar.
Planting multiple helps monarch survival.

Sell it as “Monarch nursery in a pot.”

 Growth Habit

• Upright perennial
  
  

• 3–5 ft tall
  
  

• Slowly clumping root system
  
  

• Not aggressive like Common Milkweed (syriaca)
  
  

 Planting Notes

Depth:

• Plant crown level
  
  

Spacing:

• 18–30 inches
  
  

Does not spread aggressively; safe for smaller gardens.

 Best Landscape Uses

• Rain gardens
  
  

• Wet meadows
  
  

• Pond edges
  
  

• Monarch gardens
  
  

• Full-sun pollinator beds
  
  

• Ecological restorations
  
  

Thrives where other perennials struggle.

Companion Plants

Pairs beautifully with:

• Joe Pye Weed (Eutrochium)
  
  

• Blue flag iris (Iris virginica)
  
  

• Hibiscus moscheutos
  
  

• Rudbeckia
  
  

• Liatris
  
  

• Eupatorium perfoliatum
  
  

• Native wetland grasses
  
  

Native Value

Critical monarch host plant and major nectar source. Also supports numerous beneficial insects and wetland ecology.

⚠ Common Problems

Drooping leaves

Needs more moisture.

Sparse bloom

Needs more sun.

Aphids on stems

Normal on milkweeds—let ladybugs handle them.