Friday, June 12, 2009
Dogbane vs Milkweed
Can you tell which plant is dogbane and which is milkweed? Dogbane doesn't grow in Florida but in areas where it does grow, many people use it to 'feed' their Monarch caterpillars, thinking that it IS milkweed. The result is starved caterpillars. Monarch caterpillars will not eat dogbane.
The plant on the left is dogbane and the plant on the right is common milkweed. Both have white sap.
Milkweed has hollow stems and dogbane has solid stems (thank you Jodi and Linda for these tips). Common milkweed has green stems while dogbane has red stems.
The flowers resemble milkweed in this species of dogbane but it is not the exact same flowers. Some species of dogbane grows flowers that closely resemble milkweed flowers.
If you're not sure, send a photo to someone who knows the difference. Remember, feeding dogbane to Monarch caterpillars (or rather, attempting to feed it to Monarch caterpillars) is a sure way to starve them to death!
At Shady Oak Butterfly Farm we use tropical milkweed exclusively. We're jealous! We'd love to have the larger leaves of common milkweed but it won't grow with our warmers winters - it needs cold winters.