Monarch Butterfly decline and milkweed

Native Milkweed, Asclepias syriaca.

Click here for an interesting article about the dangers of planting tropical milkweed versus native milkweed in our gardens. Tropical milkweed transmits protozoan parasites to monarch caterpillars and weakens the butterflies. We must plant native milkweed instead. The milkweed must die off each year.

So the upshot of the article is that you do not want to plant the Tropical Milkweed, Asclepias curassavica aka Mexican Butterfly Weed. Instead, you want to plant the native Common Milkweed species, Asclepias syriaca.