Last week, Jim and I visited a local garden center to pick up a few plants we needed to fill in some empty spots. I have learned to arm myself with a list of exactly what we require; otherwise, I will spend too much money, only to find that we don’t have the right spot for a perennial I hadn’t intended to buy.

While I was searching for one of my favorite low-growing perennials, Verbena canadensis ‘Homestead Purple,’ I spotted a grouping of tall, majestic foxgloves (Digitalis pupurea). I tried to grow foxgloves about twenty years ago, but the spot I selected was too sunny, and they didn’t survive the summer sun and heat.

The tall foxglove spires, bearing dainty, funnel-shaped blooms in shades of rose pink, light purple, and white were almost too much to resist, but I did, until next year, at least. I don’t have a shady spot prepared for these garden treasures, and I don’t want to repeat my mistake of years past.

Foxgloves are biennials, plants that generally live for only two ...