Q:
I want to order a Baptisia from a nursery in South Carolina to plant in my Minnesota garden. It is supposed to be hardy in my area, USDA Hardiness Zone 4 (–30°F), but I’m worried that a plant propagated and grown in a more temperate climate may not thrive in my far-north garden. Could this turn out to be a problem? I want to order the plant in spring. What if I get one that has broken dormancy while it is still too cold to plant here?
Lyn Aus, St. Paul, MN
A:
Deborah Brown, a horticulturist with the University of Minnesota, St. Paul, replies: I would not be worried about buying herbaceous perennials grown in a warmer climate, as long as they are rated hardy in your zone. A Baptisia grown in North Carolina should survive the winter in Minnesota. That’s because only its roots must be hardy, since the plant dies back to the ground in winter. Make sure you mulch your Baptisia for winter protection and to keep its roots from heaving out of the ground during early spring thaws.
However, I would not buy woody plants from a southern nursery because plants developed in the southern part of the United States are less hardy than those grown in the North. The roots and the upper portion of a woody plant must be fully hardy for it to survive the harsh winters of Minnesota. For example, conifers and rhododendrons that are grown in warmer climates are not likely to make it through our winters in very good shape.
A reputable mail-order company will know when to ship a plant to your area in the spring. Or you can tell them to hold off shipping it to you until after you’re sure it won’t freeze on your doorstep. If you can’t plant it when it arrives, keep it in a cool basement or perhaps even the refrigerator. Put it in a plastic bag with holes for ventilation, and don’t let it get too warm or too dry before you plant it outside.
