Milkweed Flowers -- © Dave Spier
Milkweeds are worth keeping at the sunny back edge of a yard because of its importance to Monarch butterflies. Eggs are laid under the leaves so the caterpillars have a ready source of food. By ingesting the toxic, white sap (containing cardiac glycosides), they acquire a defense against predators (mainly birds).
The Common Milkweed's clusters of pink flowers are attractive, but long roots make it hard to control in a decorative garden. The perennial plant is best grown in a specialized butterfly garden. A close relative, the Butterflyweed, has gorgeous orange flowers and does well in dry, sunny locations and sandy soil.
The milkweed's flowers are also important in supporting large numbers of native bees, including bumblebees, as well as non-native honeybees. Pollinators need a variety of native plants in order to get all of the nutrients they require. Large mono-culture (single-crop) fields provide only a partial source.
For the autumn perspective on the milkweed plant and more information on its uses, see the blog archives for November 15, 2011.
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