Asclepias, Swamp Milkweed, Rose Milkweed, Swamp Silkweed 'Cinderella'

Asclepias incarnata

Family: Apocynaceae (a-pos-ih-NAY-see-ee) (Info)
Genus: Asclepias (ass-KLE-pee-us) (Info)
Species: incarnata (in-kar-NAH-tuh) (Info)
Cultivar: Cinderella



Water Requirements:

Requires consistently moist soil; do not let dry out between waterings

Sun Exposure:

Full Sun


Unknown - Tell us

Foliage Color:

Unknown - Tell us


36-48 in. (90-120 cm)


18-24 in. (45-60 cm)

24-36 in. (60-90 cm)


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)

Where to Grow:

Unknown - Tell us


All parts of plant are poisonous if ingested

Bloom Color:

Magenta (pink-purple)

Bloom Characteristics:

This plant is attractive to bees, butterflies and/or birds

Bloom Size:

Unknown - Tell us

Bloom Time:

Mid Summer

Late Summer/Early Fall

Other details:

Unknown - Tell us

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)

Patent Information:

Unknown - Tell us

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


This plant is said to grow outdoors in the following regions:

Bridgeview, Illinois

Greenville, Indiana

Wichita, Kansas

Boston, Massachusetts

Brockton, Massachusetts

Dracut, Massachusetts

Townsend, Massachusetts

Winthrop, Massachusetts

Blissfield, Michigan

Garden City, Michigan

Pinconning, Michigan

Kasota, Minnesota

Wayzata, Minnesota

Columbia, Mississippi

New Milford, New Jersey

Trenton, New Jersey

Clifton Park, New York

Croton On Hudson, New York

North Tonawanda, New York

Wake Forest, North Carolina

Delaware Water Gap, Pennsylvania

North Augusta, South Carolina

Azle, Texas

Fort Worth, Texas(2 reports)

Los Fresnos, Texas

Salt Lake City, Utah

show all

Gardeners' Notes:


On Oct 8, 2019, janelp_lee from Toronto, ON (Zone 6a) wrote:

According the info I read, this variety has vanilla scented flowers. Any one who grow this can confirm it? Thanks!
[[email protected]]


On Sep 2, 2019, BostonPlanted from Boston, MA (Zone 5b) wrote:

This plant gets covered in monarch caterpillars! The adults love the flowers and the babies love to eat the leaves. Likes decent amount of water. Have it in full sun in pond and part shade in regular loamy soil. Blooms for a long time. By end of season (mid august) starts to yellow a bit and is usually pretty well eaten by monarchs and pretty infested with yellow aphids but it returns again in spring with vigor. Beautiful plant for helping to increase the monarch butterfly population. Will send a couple seedlings out but in no way invasive at all.


On May 19, 2015, Sarahskeeper from Brockton, MA (Zone 6a) wrote:

Got mine at a DG Roundup many years ago. Took a few years to make a statement but I love it now.
Nasty yellow aphids infest new seed pods after blooming. Deadheading or an occasional harsh water spray should deal with it.
Flowers smell like cotton candy.


On May 11, 2012, penpen from North Tonawanda, NY (Zone 6a) wrote:

Mine is planted next to a gutter down spout so it takes up the excess water in the soil that the other plants in that bed don't necessarily need. I purchased it as a starter plant in spring of 2010. Spring of 2012 it has tripled in gerth size. I am in zone 6a and cut the old canes down in spring when I see new growth beginning to emerge. Last year I had several monarch cats on it as well as hummers.


On Apr 11, 2012, cougarvamp45 from Bridgeview, IL wrote:

I planted 6 of these last year, I ordered healthy plants with a well developed root system, & planted them in full sun. They grew tall but I didn't have any flowers on them. They were well watered, not allowed to dry out. Now it's spring, & all of my others perennials are making an appearance, but not the Milkweed, which is why I'm giving it a neutral rating. Is this slow to grow in the spring? Or did they die off?


On Aug 31, 2008, Danny112596 from Los Fresnos, TX (Zone 10a) wrote:

This plant is supposed to grow in zones 4a-9b, yet I have one growing in zone 10a! This plant is adaptive. :-)


On Aug 19, 2008, gsteinbe from Trenton, NJ wrote:

This plant is vigorous. Mine get at least 4 feet tall. The flowers smell absolutely divine and are very pretty, especially up close. Lots of bugs seem to love the plants (including Monarch Butterfly catepillars, some little yellow aphid-like bugs, and bigger orange and black beetles that congregate in droves on the seed pods), but nothing seems to cause significant damage. They don't seem to bloom for long (hence my neutral rating), but they make tons of seed and look dramatic with their tall, strong stems and abundant leaves. They also don't seem to get many weeds growing up amongst them.

UPDATE: This spring almost none of my original planting of Cinderella butterfly weeds came back. I think that I may have watered them too much last year and kept them too wet. Or e... read more


On Sep 23, 2007, LeBug from Greenville, IN (Zone 6a) wrote:

I love this plant I have two planted in different spots the butterflies love it! Mine doesn't set seed, does anyone know why it keeps coming back but no seed I'v had the plants for about three years now and want to plant more!

5-16-10 Well, it's taken me forever to figure out I didn't have this one I believe it is the Showy Milkweed but have seedlings of the Cinderella I'm planting this year so I'll be back when I've had it for a year.


On Sep 13, 2006, flamingonut from New Milford, NJ wrote:

Despite being an oleander aphid magnet (as are all milkweeds), it's tall, beautiful, and the monarch caterpillars like it. I had grown mine from commercial seed, and it doesn't look as dark as most pictures I've seen online. But, there are a few that match. I'm debating whether or not to upload my photo...