Asclepias verticillata Whorled Milkweed is very short and blooms very late – anytime from August through October - relative to other native U.S. milkweeds. Like all milkweeds, it is a necessary food for Monarch larvae (please let the caterpillars eat some of the foliage) and will feed the last group of caterpillars of the summer as well as migrating Monarchs and other species. Most/full sun. Plant seeds in cold conditions. Perennial. 25+ seeds/pack. Out of stock!