Asclepias nivea

 species synonym(s) Asclepias nivea 'Curassavica' is a synonym for Asclepias curassavica
 common name(s) Caribbean milkweed
 native to Puerto Rico, Virgin Islands, Cuba, and the Dominican Republic
 zone hardiness 9b - 11
 life cycle
 perennial, herbaceous
 height 3 feet
 width 1 foot
 light requirements full sun, supposedly partial shade
 soil requirements average
 water requirements regular moisture
 reproduction by seed
 germination seed requires no pretreatment
 difficulty easy
 relationships nectar source for insects ???, host plant for all milkweed dependent insects

Experience | Opinion | Impression
This species resembles (Asclepias curassavica) in the way that it grows. The foliage has a lighter shade of green than the typical (Asclepias curassavica). The flowers are greenish white, small, noticeable, but insignificant. It seems to me that this species flowers more frequently than (Asclepias curassavica). I cannot recall seeing anything visiting the flowers, but mine have produced seed pods -- because of how milkweed flowers are fertilized, something must have visited it. The flowers have no scent, and after inspecting the flowers a couple of times I have gotten the impression that it produces very little nectar.

A retail source for seed is available from Vivero Anones; they ship to most locations.

I have grown mine in my garden, which has a high clay content, where I treat them as annuals, and in pots with pH balanced potting mix, and I attempt to overwinter the potted specimens inside but with little success. It seems they need bright light to remain healthy over the winter. I assume it can go dormant, but have not tried to maintain a dormant plant through the winter. I water the potted specimens almost daily, if not daily then no less than every three days. This species requires drainage, which limits where I can grow it in my yard, since some spots in my garden can pool the water for a few days. The 3 quart pots I use have a 1 inch depth saucer, but from what I have observed of this species is that the saucer is usually deeper than the roots penetrate. Specimens can survive in smaller pots, but with less vigorous growth and potentially needing to be watered twice a day. If starting from seed, and planning to transplant outside, they need to be transplanted early, but after all spring frosts, so that they will have enough time to flower and potentially produce mature seed pods. From descriptions I have found, this species supposedly can survive in a partial shade situation, which makes me wonder what I am doing wrong when I overwinter mine inside, unless of course they are actually going dormant for the winter. I have tried growing them under a grow light, but they steadily declined -- I suspect that had I increased the grow light intensity they might have survived on artificial light, but it is cheaper to set them next to the window.

This species gives off an unpleasant odor, but it is not particularly strong. The odor is only noticeable when the foliage is ruffled, or especially when it is clipped.

digital images
Here is a photo of seedling. It's first true leaves showing the veins.

A potted specimen, that is not in good shape, but shows the flowers and their color (yellowish green petals and white center). There is a pet feline in the background propped up and looking out of the window.

Here you can see two seed pods, one nearly mature (center), the other just beginning to develop (top right of the photo).

pertinent hyperlinks
Dave's Garden
New York Botanical Garden herbarium

photos of a Monarch butterfly ovipositing on this species here and here
photos of this species in flower, here and here (the flash has washed out the green in flower petals)
herbarium specimens: here, here, here, and here
a photo of the flowers is posted here