Hardy shrub roses include those developed by Agriculture Canada, in Eastern Canada (the Explorer Series) and those bred on the prairies (the Parkland and Morden Series as well as those developed by other Canadian plant breeders). The hybrid teas and the David Austin varieties require added protection to overwinter on the Canadian prairies.
When the Morden Research Rose Program closed in 2010, the rights to the rose lines were awarded to the Canadian Nursery Landscape Association. The Artist Series of roses, ‘Emily Carr’, ‘Felix Leclerc’, ‘Bill Reid’, ‘Campfire’ and ‘Oscar Peterson’ came out of this consortium. More recently, the Vineland Research & Innovation Centre in Ontario, in partnership with the Canadian Nursery Landscape Association, continue to introduce new hardy roses. The roses known as the 49th Parallel Collection include ‘Canadian Shield’, ‘Aurora Borealis’, ‘Chinook Sunrise’ and ‘Yukon Sun’. Any of these relatively recent introductions are well worth a try.
Hardy roses are propagated on their roots and are sold by nurseries as potted plants. They should be planted in a sunny location with good air circulation. To flower, roses require at least six hours of sunshine per day. Dig a hole 45 cm deep and wide. Amend the soil with compost or well-rotted manure, or better yet, replace poorer soil with good quality soil with compost added. If available, throw some alfalfa pellets into the planting hole, they are a good organic fertilizer, which will fix nitrogen and give the rose a boost. Roses should be planted at the same depth as when in the pot. Leave a “well” or dike around it to ensure that the roots are well hydrated with each watering. After planting, water well, then place an organic mulch (wood chips, post peelings, dried leaves) 7-10 cm deep on the soil surface around the rose to conserve moisture and discourage weeds.
Your rose will require approximately two and a half centimetres of water per week. To avoid diseases such as powdery mildew, rust and blackspot, water the soil rather than the foliage. If you must water with a sprinkler, do so early enough in the day to allow the rose foliage to dry thoroughly before nightfall. If possible, select varieties which are resistant to these diseases. Be diligent about pruning out rust. It can spread to adjacent roses, even those said to be resistant.
These roses usually do not require fertilizer in their first year. In subsequent years, to encourage bloom, apply a fertilizer with a higher middle number in the spring. I only fertilize once a year, but you can apply a weaker soluble fertilizer every two weeks. Stop fertilizing in early August to allow plants to rest, harden off and discourage new growth before winter.
Prune your roses in the spring, as soon as they show healthy vigorous growth. Remove any old canes that show no sign of life, as well as canes that show spindly growth or crossing branches. Whenever possible, prune to just above a leaf bud that faces in the direction you want the rose to grow. Generally, this will be an outfacing bud, but sometime you may want a shrub rose to fill in at the centre. If you cut too far above the bud, the rose will expend unnecessary energy trying to feed this area, but to no avail, as that section will generally die back to the bud anyway. This energy is better used in the development of new growth.
Deadhead your roses after blooms are spent, pruning them back to an outfacing bud. This signals the rose to develop a new flower cluster. I try to prune before August, after which I allow rose hips to form which provide winter interest and food for the birds.
Since roses often suffer dieback in winter, avoid pruning them in the fall, although you may want to cut back very tall canes to prevent winter wind damage.
Besides the added benefit of more flowers, pruning your roses brings you up close and personal with these beauties, providing an opportunity to inspect them for diseases and problems that may otherwise be overlooked.
— This column is provided courtesy of the Saskatchewan Perennial Society (SPS; email@example.com ). Check our website (www.saskperennial.ca) or Facebook page (www.facebook.com/saskperennial) for a list of upcoming gardening events.