by Lois Berg Stack, University of Maine Cooperative Extension, Leonard P. Perry, University of Vermont Extension, Robin Borok, University of Maine Master Gardener Volunteer
Roses in northern New England face many challenges, including long, cold winters that often kill hybrid roses. Shrub roses offer an excellent alternative to hybrid teas, grandifloras and floribundas. But which ones are reliably hardy? In 1997, we initiated field trials to address the question of shrub rose hardiness at two sites: the University of Vermont's Horticulture Research Center, South Burlington VT (USDA Hardiness Zone 4B), and the University of Maine's sustainable agriculture research facility, Rogers Farm, Stillwater ME (USDA Hardiness Zone 5A). We obtained roses from commercial sources, planting one plant each of many species and cultivars, with considerable overlap of cultivars at the two sites. We add more roses each spring, and the plantings now contain over 130 cultivars at each site. At both sites, roses are spring-planted, mulched, fertilized, and watered as needed. At the Stillwater ME site, roses are top-mulched with 12" sifted compost in November of their first season, but not winter-mulched in subsequent years.
Each year in early summer, all roses at each site are rated for winter survival, on a scale from 1 to 5:
2 Weak spring growth (25% regrowth compared to previous year)
3 Good growth (50% regrowth), with significant spring pruning required
4 Very good spring growth (75%), with minimal spring pruning required
5 Excellent spring growth (close to 100%), with little or no spring pruning required
A rose rated "5" for several years would perform well in a low maintenance landscape. A rose rated "3" for several years would be appropriate for a northern New England landscape where spring pruning is an accepted labor practice.
Based on 3 years of hardiness ratings at each site (1998-2000 in Burlington VT and 1999-2001 in Stillwater ME), we've selected 15 shrub roses that seem to perform well in northern New England conditions, with the following caveats:
2-All selected roses are planted at both trial sites.
3-Winter hardiness data have been collected at each site for at least 2 years on each of these roses.
4-None of these roses received a rating below "3" at either site.
5-All of these roses received an overall average score above "3."
Alba Roses: free-branching shrub roses with relatively few thorns; semi-double to double, highly fragrant flowers in clusters of 5-7 in June; flowers produced on shoots from second year wood.
Height 6'; also called 'The Jacobite Rose'; double white; highly fragrant.
Rosa 'Félicité Parmentier' (ME ratings 5,3,4; VT ratings 5,4,3; average rating 4)
Height 4'; pale pink double flowers; reportedly the most fragrant Alba.
Rosa 'Königen von Dänemark' (ME ratings 5,3,4; VT ratings 5,5,3; average rating 4.17)
Height 5'; darkest pink flowers of the Albas; highly fragrant.
Height 4'; striped form of the deep pink 'Apothecary's Rose'; semi-double; fragrant.
Rosa 'Charles de Mills' (ME ratings 4,4; VT ratings 3,4,3; average rating 3.6)
Height 5'; crimson-maroon flowers in June; fragrant.
Rosa 'Tuscany' (ME ratings 5,5; VT ratings 5,4; average rating 4.75)
Height 3'; velvety crimson-purple flowers with white flecks in June.
Height 8' (climber); medium red flowers that repeat somewhat through the season.
Rosa 'John Davis' (ME ratings 5,5,4; VT ratings 4,4,4; average rating 4.33)
Height 8' (climber); medium pink flowers in many-flowered clusters.
Rosa 'John Cabot' (ME ratings 4,3,4; VT ratings 4,4,4; average rating 4.6)
Height 8' (climber); medium red flowers.
Height 5'; crimson purple flowers in June.
Height 5'; medium pink flowers.
Rosa 'Canary Bird' (ME ratings 4,5,3; VT ratings 3,5; average rating 4)
Height 5'; single yellow flowers; among the earliest of roses to flower; distinctive reddish thorns.
Height 8'; also called "Sweet Briar Rose"; light pink single flowers; fragrant leaves.
Rosa eglanteria 'Magnifica' (ME ratings 3,3,3; VT ratings 5,5,5; average rating 4)
Height 8'; lilac pink flowers.
Rosa acicularis (ME ratings 4,5,4; VT ratings 5,4,5; average rating 4.5)
Height 5'; light pink; also called "Arctic Rose"; early flowering.
return to Perry's Perennial Pages | Sustainable Perennials Research