It irks their stomachs, and makes this plant off-limits for deer: a boon to those of us who love blue flowers and lush, glaucous foliage.
I tried to grow this plant from seed, but the tough seed coat and freshness of the seed make this almost impossible, as I learned. Fortunately, I was able to find a potted root cutting at a local nursery, which has thrived in my acid soil (on a granite ridge) and is now a metre-wide rootball, which I plan to divide this coming spring to produce a hedge along a rocky outcropping. The plant is sterile but I will report on my success (or failure) of spring propagation by division and replanting. Pictures to follow.
The plant, once established, produces a cascade of blue flower clusters in late spring, which drop off (being infertile), and then the foliage forms a disease-free, deer-free foliage mass similar to a peony after it has bloomed. These are useful garden architecture elements.
Success with baptisia vs deer
Andy, the seed needs cold stratification. I've germinated the seed by leaving it in the refrigerator with damp medium in a plastic bag. Best to start in the fall as it takes several months. When you see the root emerge, you can plant it up. Otherwise, plant it outside in the fall in a pot and keep it for a long time. A light sanding of the seed coat might help.