PlantFiles: Bloodflower, Swallow-wort, Butterfly Weed, Mexican Milkweed, Scarlet Milkweed
Asclepias curassavica

I originally ordered seeds for this plant from a Monarch butterfly website back in '91 when I was living in Monterey, CA. The plants did fairly well, but didn't like the cool weather and shady conditions it had. It bloomed, but didn't set seed the first couple years. Fortunately, my original seed remained viable during those years so I was able to restart some each spring. Finally, I got one to develop seed so I was resupplied.

I then moved here to Colorado Springs with a warm sunny backyard. The plants exploded into growth, bloomed, and produced copious amounts of seed. I'm now set for life, I think. The first summer the seed pods opened and seeded themselves in several of my other potted plants which were then over-wintered indoors. The following spring I had even more plants and subsequent seeds, and now have three baggies full. I'm just about to start some indoors for this summer, and plan on going a little crazy with them and planting them all over.

The plants are not freeze hardy, so I don't think they'll be invasive here, unless it turns out the seeds can survive winter freezes. I guess I'll find out this summer if I find any volunteers sprouting from last year's seed, which got all over last fall because I couldn't keep up with harvesting all the seed pods. I had dozens.

These plants have become infested with yellow aphids every single season I've grown them. The infestation usually occurs early in the season before many butterflies show up, so I give them a quick spray with vegetable safe insecticide that is safe within 24 hours, and that clears it right up. The infestation usually doesn't reoccur after that.

If grown from seed in my Z5 - Must be started indoors early, to be able to collect seeds for growing again, the next season. It is a tender perennial here and will not reseed itself, nor come back from it's roots. Easy way to have a lot of Milkweeds for the hungry Monarch caterpillars. Which are another reason for the need to start early here. They arrive in mid July here - so you need to have your plants practically ready to set seed. Otherwise they will eat it all up before it has the chance. They eat it down to stems - but tend to leaves some seed heads, if they are there. They will eat the blossoms too. I have detailed starting info in my seed starting journal here http://davesgarden.com/community/journals/viewentry/234736/

I bought a package of seeds a few years ago, picturing red-and-yellow and yellow butterfly weed, supposedly Asclepias Tuberosa and hardy to zone 5. It seeded very readily in my upper-edge-of-zone-5 garden, made huge 3 ft plants that flowered abundantly from about July on. We had lots of Monarchs camping out in our garden. Well, the supposed zone 5 plants did not come back the next spring but had left hundreds of seeds behind that sprouted liberally everywhere. I had so many I potted them up and gave them away, and I still had about 200 plants (most were red-and-yellow) that summer, and even more Monarchs. Thousands of seeds were flung all over so I'm hoping for a liberal crop this year, too. I'm sure what I'd gotten was really Asclepias curassavica. Even though the original plants don't overwinter up here in south-central Wisconsin, they leave behind enough seeds to populate an entire neighborhood!

Here in Houston zone 9a, I can just cut the canes which get almost 5 feet tall, and stick them in the ground or in a pot and they take root and grow. About 1 week ago, my biggest plant looked like a caterpillar bush... not a leaf left on it and covered with about 40 big fat caterpillars. The next day I found them crawling everywhere looking for a place to "hang". I and my neighbors enjoy them so much. I have not seen any "volunteers" from previous year's seed. It's probably too windy here. My seeds may be in Oklahoma by now! I was disappointed to find the huge strange-looking aphids but I used the soap and they were gone quickly enough. Ive planted lantana, pentas and Mexican flame vine for the adult Monarchs to use as nectar plants.

I've considered a milkweed for my butterfly garden but have been concerned about it spreading. We have a horse farm and I don't want it to get out into my pastures. I posted on the Herb forum about it and a gal in Tx said she said not all varieties are invasive. Which ones aren't? Also, I've got a protected spot (corner) where I have my herb garden by the house and porch. Would it grow in a pot there (lots of sun) if I put it in a pot and deadheaded it? I could keep a close eye on it there.
Thanks for any advice

I only planted this 1.5 yrs ago and it seems butterflies haven't quite acknowledged my garden as butterfly friendly. My plant was splindly so I cut it and rooted it in water. After 3 weeks I had 2" roots and potted them since it is Nov. I will transplant inground next spring.

This plant was bought in May of 2008.

It spreads out very quickly. I bought it for our Butterfly Garden. It is interesting to see it has popped up in other areas in my yard from the seeds blowing around.

I keep it cut back between 30" - 38" Tall & try to keep it under 48" Wide. Due to the seed pods popping open before I can collect the seeds, It can overtake your garden if you don't watch it.

Humminbirds have been seen hanging around this plant in addition to butterflies & bees.

Was given some seed and started the plants late in May and not planted out until June. It grew quickly in the worst clay in my garden and bloomed late July with vibrant lovely flowers. The plant is robust and healthy and I will definitely add this one to my list of fun annuals to grow! Such colors!

This plant grows very well in the New Orleans area. Many nectar/pollen insects and hummingbirds are attracted to it. It self-seeds easily. It can also be transplanted if you remove a large and deep amount of soil with the roots.
The major problem is with severe infestations of yellow aphids. Infestations have been so bad that some plants have been killed. According to info on other pages, the normal aphid predators are poisoned by them because they absorb the toxic sap from the milkweed. I also have problems with milkweed assassin bugs infesting the plants and attacking insects that are attracted to the plants.

I recieved mine in a plant trade from one of the members on DG. It did very well for me, starting from young plants. I hardly watered it and it had very showy blooms. I noticed in early August this year the Monarch butterfly larvae were feasting on it. Great, I love to promote butterfly production. The seed pods were a long pointy paper looking seed pod which contained the "fly away"seeds. Each seed was tethered to a light white fiber that helped it to be drifted by the wind. I collected all the seeds I could and plan to plant the seeds in my new raised garden bed for next year. Considereing the extream drought of this year, I would definitely recommend this plant for conserving water needs!!

I got a few seed pods from my neighbor's plant (who has no idea where it came from). Every single seed sprouted and all seedlings are doing excellent. They do very well in our area.

One thing though, pinch out the centers to have the plant branch out more. It doesn't take much pinching to get it to branch. I'm doing this before they are large enough to bloom so that they will be fuller and provide more blooms.

I'd the flower in a pot for the first time last year. I just dug it up and planted into my 'cutting garden' for the first time. Very tolerant plant. One surprise characteristic that I've discovered. That this plant doesn't mind being in a boggy situation. It tolerated drought too. (sounds like that of Mexican Pertunias -- scary!). I found my potted planted wilted due to lack of water. Soaked it in bucket of water and forgot it for an extended time (talking about neglected to both end of extremes). It seems to prefer more boggy than not enough water. The plant was left in a pot all winter long, and there is signs of life. The seed head ripen and cracked open and would be flown off. Wherever it lands it germinates.

Note: In my garden these can be treated as perennial* and the butterflies love them.

In SCentral Alabama this plant gets eaten to the stubby stem late every year by Monarch butterflies. I tried A. incarnata and they won't bloom here even though they grow. Amazingly they find my little stubby incarnatas and eat them too. To feed butterfly adults curvassiaca works as well as incarnata.

Bloodflower, Swallow-wort, Butterfly Weed, Mexican Milkweed, Scarlet Milkweed Asclepias curassavica is Naturalized in Texas and other States, and is a magnet for butterflies.

My dad has this plant growing wild at his house. He dug me up one last year and we loved it. It bloomed all summer long. It puts out these very vibrant orange/yellow flowers that the butterflies go crazy over. Mine got really tall and it was covered in blooms. It did die down over winter, but I am happy to see that it is coming back up very quickly.

I have had very good luck with both of these plants. I live in the piney woods of East Texas and my land is part shade and they do fine. They do die back and I have to reseed each year. We are realy in zone 8a but the map puts us in zone 7b. I was so happy to hear that they will reseed so I'am going out right now and see if I have any comming up. Thank you all for all of the good information about this beautifull plant. Joan

In my native Maryland, zone 7b, I grow this as an annual. It's helpful to start the seeds inside in early spring or even sooner or else you won't get blooms until late winter or early fall.

Since these are growing as annuals I can't say my plants ever have the chance to get that tall and so the butterflies usually pass over the curassavica for one of the taller perennial milkweeds.

I've noticed curassavica's leaves are a lot more tender than my perennial, hardy milkweeds and so the monarchs prefer the foliage as larval food.... and so do the aphids which cover the plants almost entirely.

The other milkweed bugs, such as the beetles, usually pass this milkweed over because it never becomes thick enough for them to bore into or provide substantial food, or support their weight.

Despite the name, tropical milkweed can hold up very well with drought, only requiring occassional rain. However, the more rain and humid temperatures, the faster and better it will grow.

Tropical milkweed is ideal for beds, butterfly gardens, borders and are very compatible with container plantings.

In Delaware and South Jersey, the Butterfly Weed grows in sunny fields, particularly on the perimeter of corn fields. It doesn't get more than 2 feet high (because we have shorter summers?). Ladybugs like it, also. I tried to transplant it several times, and if it made the transfer, it would only grow one season. The tap root may have to be intact, and deeper than the frost line? I'm trying a purchased plant this year.

This is one of my favorite plants it is beautiful and the butterflies do loveit I too have had the little yellow aphids with black legs on mine and they seem to be eating holes in the leaves so I have been washing them off as i dont want to kill the butterflies. I will have to transplant them to a new bed because they are getting to tall for the front of the bed they are in but thats ok. ill just replace them with shorter plants.

My Asclepias curassavica is in full flower today, January 5, 2004, in Sebring, Florida. It tends to go through cycles of more and less flowering every couple months or so all year. This plant is really tough here, and can escape from cultivation if discarded carelessly.

Wonderful butterfly plant. I have mine interplanted with passifloras and have had lots of butterflies. The aphids don't seem to damage mine, just colonise the plants, so I don't spray, since i don't want to kill the butterflies. Lots of seeds, so they're great for sharing with everyone. I planted mine and ignore them and they thrive. My kind of plant.

An excellent butterfly attractor and a great multiplier. One plant will make many before too long. It self seeds and it will...everywhere. I have moved several out of my main bed to the fence row and also have several potted for sale. The downfall to mine has been that it is susceptible to rust. I at first was using pesticides before I realized the butterfly feed on it...use fungicide instead. Clip off any diseased leaves...it likes to be pruned...new shoots will appear free of disease...keep it sprayed if the rust comes back. It has been a battle for me but I have enjoyed watching it grow. Like tall soldiers...plant in the back for sure. I also had problems with aphids but they didn't seem to damage the plants like rust. Put a pot in the front yard for Halloween...fall color. :-)

San Antonio, Tx

This is an excellent tall xeriscape plant that takes at least a year to become established with more branching enabling more blooms. The seeds float off and readily create new plants that can be transplanted or potted and given to friends and neighbors. This must be accomplished when the plants are small. It has a long tap root, so it is somewhat tricky to transplant once established. If heavy invasions of aphids and other insects are not removed, the leaves become an unattractive, mottled yellow/brownish color. Butterflies and bees love this plant which blooms constantly from June to early September in my zone. Being a perennial, it dies back after the first hard freeze and reappears in early spring. Do not overwater because the leaves will yellow and drop off. It prefers well drained soil and performs best in full sun. Be sure to plant in the background.

i planted one plant last year, the red with yellow and orange and by the following year i had more all over the place. since they are so tall i had to transplant to the back. it was a little difficult to get the roots, but they finally came up. This year i only had one, but now they are slowly coming back and again all over the place. but i really love this plant they are a little invasive but the blooms make it okay.

I bought my A. curassavica for a few dollars at a discount store last summer labeled "scarlet milkweed" and after some research I finally found the scientific name. The little cheap plant became almost five feet tall in its pot last summer, growing in part shade in zone 8b, with beautiful red and yellow small blooms until frost. I even had new seedlings growing in the pot. Last October I transplanted the mother plant and several of her seedlings into a well fertilized and heavily mulched raised planting bed and this spring, after our coldest winter in 100 years in Northcentral Florida, they all came back up. Unfortunately our rainy summer has lessened the flower display, but the mother plant is sporadically blooming. Bright yellow-orange aphids were a problem this spring, but I persistently washed them off for about a week and they went away. Some local native plant enthusiasts deplore planting scarlet milkweed as it is from South America and seems to be of easier culture than our native milkweed, A. tuberosa. They think it will push out A. tuberosa, which I have have found to be difficult to grow. But I think if planting scarlet milkweed will help the threatened Monarch butterfly, then native or not, we should plant it. It seems of very easy culture, reseeding in the garden, and very easily transplanted when young.

Very nice pictures from a very interesting plant.

I like the colorful flowers which attract butterflies. This plant blooms through the winter when almost everything else is dormant. It is a great larval host plant for the Monarch and Queen caterpillars. Spider mites and Oleander aphids (the yellow-orange ones with black legs) can be somewhat unsightly, though they don't seem to harm the plant. Caterpillars have eaten the growing buds completely away and the plant will sprout back from lower on the stems or at the base of the plant. It will do the same after a hard freeze. It also grows readily from seed.

Scarlet milkweed is an erect, evergreen perennial shrub, often grown as an annual in colder climes. It gets about 3-4' tall and usually has a few pairs of symmetrical branches. The flowers are orange and red and 2-4 inches across, blooming continuously from spring until autumn. A cultivar with yellow flowers is available.
Scarlet milkweed is easy to grow, thriving in all types of soils in Zones 8B - 11. It remains evergreen in zones 9B-11, but if it does freeze to the ground, it usually comes back in spring. Scarlet milkweed can be started from cuttings, and it grows quickly from seed.
Butterflies and other nectar-sipping insects are attracted to the blossoms, and both monarch and queen butterflies lay their eggs on scarlet milkweed
All milkweeds are poisonous if ingested, and the milky sap is a skin irritant.