Shrub roses are becoming more and more popular for mixed borders. Their open, graceful habit, long flowering period and sweet fragrance make them ideal companions for perennials.

Planting shrub roses . . .
When choosing a shrub rose know the height and width of the mature plant and allow for its growth. Check the plant for hardiness and disease resistance. Plant when the air is still, in the early morning or the late afternoon.

A minimum of six hours of sun encourages the best performance. Have some protection from winds (fence or hedge). Good water drainage is also essential. Clay soils are preferred by Rosa multiflora and R. canina while R. rugosa and Scotch roses on their own root stock prefer lighter soils.

If you're planting bareroot shrubs, plant in fall or early winter; or in spring in very cold regions. Place the plant in water and let it soak up to 12 hours before planting. Check roots and prune off any injured or broken roots.

If there is a root ball, soak well up to 12 hours. If the roots are massed, make several shallow cuts up and down root ball to force formation of smaller roots.

Dig a hole wide enough for the roots to be spread wide and 18" deep. In the bottom of the hole mix compost or well-rotted manure with a handful of bonemeal. Place the shrub in the hole so the bud union is 4" below the surface; or, if the rose is grown on its own roots, keep the same soil level. Fill the hole and tamp down the soil to eliminate all air pockets. Water well.

Transplanting shrub roses . . .
This can be done any time of the year, but it is best in early spring or late fall. After planting, prune off one half to two thirds of the top growth. Spray tops with water for first while to help plant retain moisture.

Fertilizing shrub roses . . .
Healthy soils contain a high ratio of organic matter. he best way to fertilize shrub roses is to ensure that the soil has a high level of organic material such as manure and compost. Fresh manure provides nitrogen, but it can cause burn damage. Instead, use bagged manure for a good soil amendment. If nitrogen is needed add bone meal, blood meal, feather meal, fish waste, linseed meal, soya meal or cottonseed meal to the soil. Compost, a natural, mild fertilizer, must be renewed regularly to maintain its effectiveness.

Packaged fertilizers will give a quick boost but they do not contain the micronutrients that are essential to plant health. As they dissolve they acidify the soil, therefore lime must be added from time to time. Do not use chemical fertilizers after mid-July so that the plant can harden off for the winter. If used, use 6-10-4 for spring application and 5-10-5 for July application. Apply accurately as specified on container.

Mulching shrub roses . . .
Mulching provides continued micro-organic activity. It tempers soil temperature and maintains soil moisture. Possible mulches include wood chips, sawdust, compost or straw.

Remove previous year's mulch in the spring, to weed and clean the site. This discourages the growth of overwintering fungi spores. Work in a fertilizer such as bonemeal and compost, then mulch with new material. Apply one to three inches of fresh mulch every spring.  

Winterizing shrub roses . . .
Canes can be tied in early winter to prevent wind damage. Although most shrub roses are very hardy and require little winter protection, you may wish to protect your roses with a 6" mound of earth around the base of the plant. Bring in soil from elsewhere for this purpose.

Pruning shrub roses. . .
Pruning is a dwarfing process, so do the minimum possible. Remove all dead and diseased canes at ground level. As the bush ages, cut out oldest canes at ground level. Thin out and shape if necessary. Prune in early spring as leaf buds begin to swell. Late summer pruning could cause winter damage. Cut 1/4" above an outward growing bud and slope the cut slightly away from the bud.

Pegging shrub roses. . .
Long young canes can be bent over until they arch to just above the ground. These can be held in place by pegs in the ground. Over the summer, flowering laterals will grow all along the upper surface of the canes. The following spring, release the pegged cane and prune off the top portion. This provides need new growth to lower part of shrubs.

Controlling insects and diseases. . .
Accept a certain amount of damage as normal. A mixture of Trounce and garden sulphur provides both an insecticide and a fungicide. Encourage birds to stay as they eat their weight in insects daily. Manual controls include picking off insects, and using a strong spray of water on aphids (once washed off aphids do not have ability to climb back up plants). Chemical sprays kill beneficial as well as harmful insects, destroying the natural balance of insect controls.

Caring for climbing roses. . .
Tie up long, vigorous shoots as the plant grows. Select disease-resistant varieties such as William Kordes and the Explorer series. Check ties regularly; keeping them loose to allow for growth.

Prune in spring for dead or injured wood only. Prune again after flowering. Main canes grow like trunks. These send out laterals, which send out sub-laterals which flower. After flowering, cut back blooming laterals to two or three eyes.

In winter, tie canes compactly around the rose trellis or support with heavy, soft twine. Protect the canes with evergreen branches tied all around the plant.

Read more about shrub roses. . .
Robert Osbourne, Roses for Canadian Gardens
Allan A. Swenson, 100 Oldtime Roses for Gardens of Today
F. F. Rockwell and E. C. Grayson, The Rockwell's Complete Book of Roses
Sinclair and Thodey, Gardening with Old Roses

Contributor: Pat Gray, Master Gardener

Factsheets are provided by the Toronto Master Gardeners and are intended for personal use and study purposes only. Should your gardening group or organization require multiple copies, please contact the Toronto Master Gardeners at tmg@infogarden.ca.