One of the hottest trends is the growing of perennial flowers in containers. If you’ve got flowering houseplants, technically you’ve been growing perennials in pots all along. What is new is taking hardy varieties out of the flowerbed and giving them a starring role in seasonal container displays.
Driving this fad is the popularity of container gardening, combined with an explosion of new perennials with novel and flashy foliage, more flowers and a longer bloom season. Also swept up in the enthusiasm are many old garden favorites, like coreopsis, gaillardia, sedums and rudbeckia, their potential as container garden subjects newly recognized.
No perennial better exemplifies the foliage craze than the coralbells Heuchera hybrids and their cousins, the foamy bells Heucherella hybrids. Purple leafed “Palace Purple” took the gardening world by storm in the 1980s. Since then we’ve seen coralbells and foamy bells with orange, yellow, gold, chartreuse or black foliage in every imaginable variation and contrasting venation, variegation and overlay, leaf form and size. These improved forms have become instant classics for garden and container culture alike.
The success of coralbells and foamy bells points out a real advantage to gardening in containers. Both of these plants require fast draining, humus-rich soil, conditions easily met with a good quality potting soil.
Besides giving the gardener better control over environmental conditions – soil type, drainage, fertility and water – there are other benefits to gardening in containers. Pots that aren’t too large and heavy are easily moved. You can follow changing sun patterns through the season or drop a container of flowers into a bed that is experiencing a case of the blahs. Also, pots are easier to tend, requiring less stooping than the same plants in the ground.
It’s a simple matter to cover container gardens in inclement weather, whether threatened by an early or a late freeze, untimely snow or a hailstorm. Containers also are useful for growing immature perennials into a larger size that won’t be readily lost in the garden. By the end of one summer of pampering in a container, most are ready for transplanting to a permanent home.
The one real limitation to gardening in containers in our region is winter’s cold. When you read that coralbells make the perfect container plant because they are evergreen in winter, you know the author lives someplace where temperatures don’t drop much below freezing.
During the winter, you’ve got several choices. Treating perennials in containers like annuals and letting them die over the winter is one. Another option is choosing the largest frost-proof container you can find and watering it throughout the winter. I’ve had some success with beach wormwood and lilies in whisky barrels next to the house.
For those plants that I value, I dig up and transplant into my vegetable garden, where they spend the winter under a thick blanket of organic mulch. (In the spring these go back into container displays.) That’s the beauty of gardening with perennials. Most don’t mind this twice-yearly upheaval. In fact, quite a number actually thrive on this regimen.
Marcia Tatroe is a garden writer and lecturer. E-mail her at rltaurora@aol.com.
