The scientific name for Swamp Milkweed is Asclepias incarnata. It blooms from June to August and thrives in sun to partial sun.
As the name indicates, it's native habitat is "swampy". In spite of this, I have had no problem growing it in my suburban garden with clay soil and little extra watering.
I have found Asclepias incarnata at our local nurseries and garden centers. It is also available through many garden catalogs.
There is a white variety, Asclepias incarnata alba, but my experience proves it is not as popular a plant with the Monarch butterflies. Also, it hasn't thrived as well as the standard, rose-pink one in my garden.
It takes a couple of years for this milkweed to become a full, mature plant.
Once you plant Swamp Milkweed in your garden, you will see female Monarch butterflies fluttering above the plant and then touching down briefly on the leaves.
If you inspect the underside of the leaf, you will usually find an egg.
This is where the fun begins......remove the leaf and follow my instructions under
"Raise Monarchs"
If you put several of these plants in your butterfly garden......the Monarchs will come.
Combine these with some annual
Tropical Milkweed
plants and you will be in "Butterfly Heaven"!