Photo: aarongunnarCC BY 4.0via iNaturalistresized / cropped
Swamp Milkweed Plant Care
Asclepias incarnata L.
Updated · Sources · How we source care data
This plant's lance-shaped leaves are a striking shade of green, originating from North America. Asclepias incarnata is highly sought after by plant collectors for its vibrant pink flowers that attract butterflies and other pollinators to the garden.
Every 7–10 days
Full sun
60–85°F
40–60%
At a glance
How do you care for Swamp Milkweed?
Water Swamp Milkweed every 7–10 days, letting the top layer of soil dry out between waterings, and give it full sun. It prefers temperatures of 60–85°F (16–29°C) and 40–60% humidity. Fertilize it every 6 months during the growing season. The ASPCA lists it as toxic to cats and dogs, so keep it out of reach of pets.
Where Is the Swamp Milkweed Native To?
What Is the Swamp Milkweed?
Swamp Milkweed (Asclepias incarnata) belongs to the Apocynaceae family within the Asclepias genus. Swamp Milkweed is native to North America. Swamp Milkweed is also known as Rose Milkweed, Red Milkweed.
Swamp Milkweed displays an upright, clumping perennial growth habit, reaching up to 3 ft tall with a spread of approximately 2 ft. Swamp Milkweed produces clusters of small, colorful flowers in shades of pink, orange, or yellow.
Leaf size: approximately 6 inches.
How Often Should You Water a Swamp Milkweed?
Asclepias incarnata requires watering every 7–10 days. Allow the top layer of soil to dry between waterings to prevent root rot. Reduce watering frequency during winter when growth slows.
Watering Frequency
Every 7–10 days
Let soil partially dry between waterings
What Light Does the Swamp Milkweed Need?
Swamp Milkweed thrives in full sun.
Light Requirement
Full sun
What Temperature and Humidity Does the Swamp Milkweed Prefer?
Asclepias incarnata grows best at temperatures of 60–85°F. Swamp Milkweed prefers humidity levels of 40–60%.
Temperature
60–85°F
Humidity
40–60%
What Soil Mix Works Best for a Swamp Milkweed?
Well-draining sandy loam with some organic matter. Good drainage is essential for Swamp Milkweed to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Swamp Milkweed?
Feed Swamp Milkweed every 6 months during the growing season (spring and summer) with a balanced fertilizer diluted to the strength on the label.
Pause feeding in autumn and winter, when growth slows, and never fertilize dry soil — water first.
Fertilizing
Every 6 months
During the growing season
The PlantoScan app can remind you when to water and when to fertilize each plant.
How Do You Repot a Swamp Milkweed?
Repot every 2-3 years in early spring. Choose a pot one size larger than the current container, and ensure it has drainage holes to allow excess water to escape.
How Do You Propagate a Swamp Milkweed?
Swamp Milkweed can be propagated through seeds, stem cuttings. Similar propagation techniques also apply to tropical milkweed plant care, which shares the same genus.
Is the Swamp Milkweed Toxic to Pets and Children?
Toxic to cats and dogs
Source: ASPCA Animal Poison Control Center plant list, which covers Asclepias species (which includes Swamp Milkweed). View the ASPCA entry
This is a general caution, not veterinary or medical advice. If your pet ate a plant, contact your vet or animal poison control.
See all plants toxic to cats and plants toxic to dogs.
What Pests and Diseases Affect the Swamp Milkweed?
Swamp Milkweed is susceptible to aphids, milkweed bugs, spider mites. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.
Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.
What USDA Hardiness Zone Does the Swamp Milkweed Need?
Swamp Milkweed grows outdoors in USDA Zone 3a – 9b. It survives winters down to planting zone 3a. Swamp Milkweed is native to North America.
Hardiness Zone
Zone 3a – 9b
Keep exploring plants
Swamp Milkweed is one of many species covered in the complete plant care and identification guide, which groups plants by genus, attribute, and popularity.
It belongs to the Asclepias genus — compare its care with other Asclepias species on PlantoScan.
Asclepias is part of the Apocynaceae plant family — browse all Apocynaceae genera and species.
Swamp Milkweed thrives in bright light and direct sun — see other bright-light plants.
More Asclepias Species
Other Asclepias species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Asclepias incarnata L., family Apocynaceae (first published in Sp. Pl. : 215 (1753)) — World Flora Online record, IPNI name record, Wikidata.
- Pet toxicity: The ASPCA lists Asclepias species (which includes Swamp Milkweed) as toxic to cats and dogs. Source: ASPCA Toxic and Non-Toxic Plant List.
- Photo: aarongunnar, CC BY 4.0, iNaturalist — original.
- Hardiness zone: USDA Zone 3a – 9b, estimated from the plant's typical growing conditions.
- Care values(watering, light, temperature, humidity, soil, fertilizing): PlantoScan's plant database, filtered by automatic plausibility checks — values that fail them are hidden. How we source and check plant data.
Spotted a mistake? Email info@upvision.media with the page link — we check and correct reported errors.
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