Narrowleaf milkweed (Asclepias fascicularis). Herbaceous perennial. Food plant for Monarch butterfly.
In a good year, these plants would be missing leaves devoured by Monarch caterpillars. This is not a good year in our garden.
This is an easy enough milkweed to grow. Plant in fall. It will sit pretty much without growth, then die down for the winter. If all went well, the plants will re-emerge next spring.
Adult plants get to around three feet tall or so and spread by underground runners. If you have only one plant, they won’t set seed – so try to establish several plants.
The plants are interesting even when they’re not crawling with colorful caterpillars. They also get really interesting aphids with bright orange bodies and black legs – designer insects indeed. They don’t seem to bother the milkweeds, and they don’t invade other plants so you can leave them in place for a bit more color.