Confusing plant look-alikes: Milkweed and Dogbane

Today we are going to show you some differences between the milkweed and its lookalike, the Hemp Dogbane. Being in the same family, these plants are very similar. The milkweed has a single, strong, upright stem. The leaves are thick and pale green in color. The blooms are clustered at the top of the plant and are a pinkish color. The seed pods are large and have thick outer coatings. This is a host plant for the monarch butterfly. There are conservation efforts to help the population grow, you can help this native by cultivating it in your garden. The seed pods ripen in late summer and the seeds ride their silks on the wind. Save your seed before they set sail. Look closely, if you see weevil or beetle holes in the pods, the seeds may not be viable since they are a food source as well. The pods may need to be collected earlier in order to protect them from insects. Beware, all parts of the Milkweed have a milky sap that can cause dermatitis, you may want to wear gloves when handling the plants.
The Hemp Dogbane, Apocynum cannabinum, is a common meadow plant that is very prolific. It spreads by rhizomes and seed, making it hard to control. It is a host for many insects and butterflies like the American Lady, Grey Hairstreak and the Baltimore Checker spot. The blooms are pale green when they open and fade to white and are grouped in bell shaped clusters. The seeds also have silk and are in long, very thin pods. The upper portion of the plant is multi branched with a reddish tint to the stems in full sun. Dogbane also has a milky sap that can cause dermatitis, so handle with care. The stems are sturdy and have a fiber that can be used to make fabric, rope and string. Next time you are hiking in the meadows, quiz yourself and see if you can tell the difference!
Joyce Browning Horticulturist, Master Gardener Coordinator
Video credit: Bethany Evans Longwood Gardens Professional Gardener Program Alumni; CPH
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