Providing plants for butterflies to raise their young is a good hobby for those of us with asthma who can't have furry pets around all the time.
The Giant Swallowtail butterfly lays one egg on any plant in the Rue family, including citrus trees and Devil's Walkingstick. Her caterpillars are considered pests in citrus groves. But here in zone 7 Oklahoma, they are welcome to eat the Rue plants we grow specifically for them.
We planted a Prickly Ash, Toothache Tree or Zanthoxylum americanum, also, but the leaves are 8 feet high and we can't see caterpillar activity up there.
Oklahoma Biosurvey provides information on everything flora and fauna in our state. Their butterfly link has selected links to larger, informative sites.
The rue plants came from a gentleman in Oklahoma City who gave me two starts that I have been babying for two years. This year they are large enough to attract a single egg and the resulting Orange Dog caterpillar in these photos.
Common Rue, Ruta graveolens, likes hot dry conditions and can be sensitive to our coldest winters. Also called Herb of Grace, Rue leaves are eaten by humans as a salad green. It's believed to improve eyesight clarity.
Some believe that Rue has the power to repel disease and others believe that it dissipates negative vibrations in our lives. The leaves contain rutin.
There is a saying that the best Rue grows from a plant in your neighbor's yard but they can also be started from seed. The Seed Depot offers the seeds in a variety of package sizes, up to 5,000 seeds.