Purple milkweed seedlings

For the past four years we have been raising savanna forbs in the greenhouse. These are species that are difficult to get established from seed. We started doing this because of purple milkweed, a State Endangered Species that is native to Pleasant Valley Conservancy.

Although we have never seen a purple milkweed plant that we knew came from a seed that we planted, we have been successful in getting them started from greenhouse-raised plants. Some transplants from 2006 have become established and in the third growing season flowered (although they have not yet set seed).

An interesting thing about purple milkweed is that despite its rarity in southern Wisconsin, it really grows well from seeds. Germination rates are high, and if they are watered judiciously, transplants become established well.

The photo shows a row of purple milkweed seedlings growing in the greenhouse. These seeds were planted in flats just after Christmas, were stratified in the cold for two months, and then put under lights two weeks ago.

Raising plants in the greenhouse also gives insights into how particular species grow, what their seedlings look like, etc. For someone interested in native plants, it is a nice project to carry out.