Container designers are always on the hunt for new flower combinations to try. But they usually pass on roses, which can grow too large for pots and suffer from too much disease. Now, a spate of newer, tougher, smaller roses has started to change all that. Often sold as landscaping or ground cover roses, they come in nearly every color, bloom nonstop, and many have excellent disease resistance.
We asked landscape designer Karen Steeb of Woodinville, Washington, to combine roses with perennials, annuals, herbs, and landscape shrubs.
After growing these combinations of roses and perennials in pots for a season, Steeb pronounced the experiment a success; almost all of the roses thrived.
Steeb used roses in the Palace series - Danish-bred types that are easy to find in nurseries and garden centers, and by mail from Arena Rose Company (free catalog; 888/544-9943 or www.arenaroses.com). Roses in this series were bred with container culture in mind. About two feet tall at maturity, they produce fragrant double flowers from June through frost and beyond. Red 'Prince Palace', pink 'Romantic Palace,' and yellow 'Sundance Palace' were some of Steeb's picks for pots.
Planted alone, any of these roses would have been bushy enough to fill out a container, but mixed with other plants, they stretched and twined together with their pot-mates. Because the yellow 'Sundance Palace' in Steeb's pots was plagued with black spot (see below), yellow roses that are more disease-resistant might make better choices.
In addition to the plants that Steeb used to blend with roses, including geraniums, lavender, nandina, and petunias, there are a number of other excellent companions, such as catmint, diascia, fleabane, forget-me-nots, hardy geraniums, Heuchera 'Palace Purple', hostas, lady's-mantle, Shirley poppies, sweet alyssum, and violas.
How to keep plants looking good
Plants grown in containers need more care than those growing in the garden, since they're planted more densely, tend to dry out faster, and exhaust the soil nutrients quickly.
Apply a granular organic fertilizer (4-6-2) every six weeks throughout the growing season; water whenever the top couple of inches of soil dries out. Groom plants frequently by pinching, pruning, and cutting off spent blooms.
The black spot that plagued Steeb's 'Sundance Palace' yellow roses is a fungal disease that results in black spots and yellowing on leaves. It's ubiquitous among roses, especially on many yellow-flowered types. Some yellow roses, however, have good resistance to black spot. These include 'Aspen', a compact spreading or trailing yellow, 'Lexington', a soft yellow 2-foot upright, and 'Atlantis Palace'.