Bloodflower, Swallow-wort, Butterfly Weed, Mexican Milkweed, Scarlet Milkweed 'Silky Deep Red'

Asclepias curassavica

Family: Apocynaceae (a-pos-ih-NAY-see-ee) (Info)
Genus: Asclepias (ass-KLE-pee-us) (Info)
Species: curassavica (ku-ra-SAV-ik-uh) (Info)
Cultivar: Silky Deep Red



Tropicals and Tender Perennials

Foliage Color:

Unknown - Tell us

Bloom Characteristics:

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

Water Requirements:

Average Water Needs; Water regularly; do not overwater

Where to Grow:

Unknown - Tell us


18-24 in. (45-60 cm)

24-36 in. (60-90 cm)

36-48 in. (90-120 cm)


18-24 in. (45-60 cm)


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)

USDA Zone 10a: to -1.1 C (30 F)

USDA Zone 10b: to 1.7 C (35 F)

USDA Zone 11: above 4.5 C (40 F)

Sun Exposure:

Full Sun


Parts of plant are poisonous if ingested

Bloom Color:


Bloom Time:

Mid Summer

Late Summer/Early Fall



Other details:

Unknown - Tell us

Soil pH requirements:

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:

Bag seedheads to capture ripening seed

Allow pods to dry on plant; break open to collect seeds

Properly cleaned, seed can be successfully stored


This plant has been said to grow in the following regions:


Millbrook, Alabama

Scottsdale, Arizona

Tucson, Arizona

Calistoga, California

Long Beach, California

Napa, California

San Jose, California

Sonoma, California

Vista, California

Clearwater, Florida

Deland, Florida

Eustis, Florida

Fort Lauderdale, Florida

Palm Coast, Florida

Sarasota, Florida

Tampa, Florida

West Palm Beach, Florida

Gainesville, Georgia

Chicago, Illinois

Hebron, Kentucky

Gonzales, Louisiana

Mandeville, Louisiana

Youngsville, Louisiana

Jordan, Minnesota

Kansas City, Missouri

Marthasville, Missouri

Westwood, New Jersey

Lake Toxaway, North Carolina

Oklahoma City, Oklahoma

Baytown, Texas

Beaumont, Texas

Edna, Texas

Houston, Texas (2 reports)

Killeen, Texas

Los Fresnos, Texas

San Antonio, Texas

Willis, Texas

show all

Gardeners' Notes:


On Jun 9, 2014, Lmaris from Mission Bend, TX wrote:

This plant grows prolifically in Houston. Last winter we had 3 hard freezes (first time in years) and it froze to the ground, but re-growing from the roots within days.

Anyone who intentionally kills the butterfly larvae on this plant shouldn't be growing it in the first place. This is one of the primary host plants of monarch butterflies, and destroying their larvae is leasing to their decline. Don't want the leaves eaten? Choose another plant or go with plastic plants.

The plant is designed to lose leaves to butterfly caterpillars, and rapidly grows more. It is a joy to watch tiny 1/2" long brightly striped caterpillars grow multiples in size before building a chrysalis and emerging as a butterfly.

Blooms nearly year-round in zone 9b.


On Apr 25, 2013, bariolio from Houston, TX (Zone 9a) wrote:

This butterfly weed has done very well in my Houston flower bed in full sun. They have survived our mild winters and are growing larger. Even though they have been stripped of leaves by the hungry caterpillars, they grow right back. It is fun to find the chrysalis everywhere in the back yard, on rims of flowerpots, on my porch post, on other plants. I love seeing the beautiful Monarchs floating around the backyard. I also have Black Knight butterfly bushes and they love them. This is a beautiful plant and I recommend it to all who love butterflies!


On Mar 26, 2010, emily11 from Augusta, GA wrote:

I have found this very easy to grow in zone 7b of north GA. It's an annual here, but I allow it to reseed itself in the fall. It comes back every year, but not till early summer. Then they bloom till frost. They grow in a rain garden. After 3-4 years, I still don't get many caterpillars, but I keep hoping more will come!


On Feb 10, 2009, mjsponies from DeLand/Deleon Springs, FL (Zone 8b) wrote:

Very easy to grow, spreads easily, and gives seeds to share with others.
Host plant for Monarch Butterflies.

As far as I'm concerned the REASON to grow these is for the spray them with pesticides is a shameful !
If you don't want caterpillars, don't plant them.


On Dec 23, 2008, hummer_girl from Saint Louis, MO (Zone 6a) wrote:

I purchased this plant a couple years ago from the nursery; their tag shows hardy in zones 7-10. Since I'm in zone 5b/6a, I grow the Butterfly Flower as an annual. I collect seed pods just before they start to split and let the pod dry, and do nothing until the following spring. By then the pod has split on its own (inside a container), and I have hundreds of seeds! I do not stratify the seeds. Around May 1st, when it's warm enough to start seeds outside in pots, I plant my seeds in the container they will be growing in, in a quality potting mix (not a seed starter mix), with some slow release fertilizer mixed in, keep them moist and in a sunny location, and off they go, producing 4' plants with continuous blooms, and ruby-throated hummers regularly coming around for the nectar. For ... read more


On May 5, 2008, nblady from Mandeville, LA (Zone 8b) wrote:

The caterpillar is from the Monarch butterfly. Definitely veracious eater.


On May 1, 2008, LBRILLEMAN from Eustis, FL wrote:

It is true that this plant is eaten by caterpillars everytime it blooms...but my positive experience is to cut the plant with the caterpillars on it, cut several extra stems also...put them in a very large plastic container with a net instead of a lid on top and within 10-14 days you get the treat of a liftetime. The caterpillars develop into crysallis then watch for the crysallis to turn dark...when that happens it won't be long before you see the creation of a beautiful butterfly. I have done this numerous times and even for my daughter's classroom...what a thrill! I definitely can put up with some stripped stems in order to enjoy the beauty of nature!!!!


On Apr 8, 2007, spaceman_spiff from Saint Petersburg, FL (Zone 9b) wrote:

I've been trying to get a specimen established in my yard for several years now, but it never seems to get much of a chance except become an elongated green stick. Every time it gets to the point where it blooms, there is a species of butterfly (or moth?) that comes and lays eggs which hatch into larvae and devour each and every leaf on the plant, drastically reducing its stamina and basically halting all growth for a period of time.

I have tried my best to remain vigilant as to when it's flowering, because I know that for the next several days afterward I will need to watch for eggs and/or larvae/caterpillars. If I see a batch of eggs laid near the flower, I spray them with a garden-safe insect spray. But often they hatch before I'm aware. Occasionally I manage to get r... read more