CALGARY
ROSES FOR THE NORTH
Content Provided by Patricia Chenier
When purchasing roses for the north you should be aware that roses have varying degrees of hardiness. Hybrid Teas, Floribundas, Grandifloras and Climbers are all tender roses and in the north will usually require extensive protection to survive. Half hardy roses include the Hybrid Perpetual, Miniatures, and Polyanthas. The hardy roses are the shrub roses and these require no protection in the north. The Brownell sub-zero roses are not fully hardy on the Prairies.
Try to obtain your rose bushes from a nursery that does not trim off too much of the root system. Those fancy boxes of rose plants available in the local department store or supermarket have had their root systems butchered to fit the box. Roses are heavy feeders but have poor root systems. They require as much of the root left intact as possible if they are to survive more than one season.
There are many hardy shrub roses available today. The list is too extensive to include but some of the newer cultivars are:
|
Name | Flower Colour |
Height |
|---|
| Champlain |
dark red |
1m |
| John Franklin |
medium red |
1.2m |
| John Cabot |
medium red |
2.5-3m |
| William Baffin |
medium red |
2.5-3m |
| Henry Kelsey |
medium red |
2-2.5m |
| Charles Albanel |
medium red |
1m |
| Jens Munk |
medium pink |
1.5m |
| David Thompson |
medium red |
1.2m |
| Henry Hudson |
white |
1m |
| Martin Frobisher |
soft pink |
1.5-2m |
|
Morden Rose |
bright red |
1-2m |
There is very little difference in the care of roses whether in the north or south. The main difference is in the timing of the operations. In the southern part of the prairies, roses are mounded about the 3rd week of October. In the northern areas, by mid-October. The straw should not go on until after freeze-up to prevent rodent damage. This is usually in November but the material should be available sooner in case of early freeze-up.
Roses grafted onto Dogrose rootstock (Rosa canina) are preferred for the prairies as this rootstock has a deep penetrating root system. This enables the rose to withstand drought better. Roses on this rootstock also tend to ripen their wood earlier and this gives them a better chance of survival over winter. The only drawback to this rootstock is that it has a poor fibrous root system and is difficult to transplant.
I will not get into the regular care of roses but I wish to discuss a special technique used by an Edmonton rose grower with great success.
Mr. G.W. Shewchuk of Edmonton, Alberta (zone 3a) has grown hundreds of tender roses yearly with very little losses. He has developed his own technique for planting. He plants his roses with the graft union 4" (10cm) below the surface of the ground. Because of the depth used, the plant is placed on a slant to ensure that the roots are not buried too deep. When backfilling the hole, he does not place soil over the graft area. Instead he uses a coarse aggregate such as sand, perlite or vermiculite over the graft. This is done to permit the new growth to emerge more easily. He leaves a saucer for watering so in reality the graft is only 2" (5cm) below the surface. At first the old branches will be at an angle but the new growth will be upright. He still mounds his roses for winter but not as deeply as usually recommended. With his method, he lost only 7 out of 300 roses in 1979 and only 5 out of 315 in 1980. Most of the bushes he lost were older bushes and may have died simply of old age. He has some which are over 14 years old. His experience has shown that northerners do not have to envy their southern neighbours. They, too, can have beautiful rose gardens.
INCREASING WINTER HARDINESS
IN CALGARY
To ensure the successful wintering of permanent plants such as perennials, fruit trees, turf grasses etc. the secret is to have them face winter in a hardened condition. They must be as close to dormancy as possible and fully matured. To assist them to reach this condition, cease the use of fertilizer by mid-summer, generally. For turf, use low nitrogen fertilizers in the fall. Any fertilization of trees should be a with low nitrogen fertilizer and only after leaf drop to prevent the growth of soft succulent tissue which would not have time to harden off. In wet areas, cease cultivation by the end of July to aid the hardening process. Water only sparingly from August to October but ensure the plants receive sufficient water before freeze-up.
A. IN THE ORCHARD
In the orchard, planting a cover crop such as fall rye or oats in late July serves three purposes. The cover crop absorbs nutrients and moisture, slowing down the growth rate and aiding the trees to harden off. The cover crop also traps snow and holds it so that it will provide moisture when spring thaws occur. Grass has also been used successfully for this purpose but it must be mowed short to discourage rodents which will attack the trees during winter doing extensive damage and often killing them.
Overbearing of fruit trees leave them weakened and susceptible to winter damage. Always thin fruit crops when young. This ensures an even distribution of fruit over the tree to reduce the weakening of branches from overweight. Delay thinning the fruit until after natural fruit fall of apples in early June. Blossom thinning chemicals are not advised on the prairies. Late spring frosts may kill blossoms at any time and if coupled with chemical spraying, very few fruit will survive.
Another way of increasing the hardiness of fruit trees is by the use of stem builders. The main trunk and branches of a fruit tree are the most susceptible to frost damage. Stem building is the process of budding the desirable apple onto the frame of a very hardy crabapple. This makes a sturdier, hardier tree. If Malus baccata is used for the frame, a dwarf, low-headed tree will result. In Russia, apple trees are trained to stay close to the ground to take advantage of snow cover. Good crops have been reported using this method. In Quebec, orchardmen are starting to use a method called Swiss pruning to keep trees low for ease of spraying and picking. It is used to rejuvenate standard apple trees which have grown too tall. I have not been able to determine if the Russian method and the Swiss method are the same but the descriptions are very similar. It is a method of training apples that should be looked at for the north.
B. ROSES
Roses are considered too tender to over-winter in the north but this has been proven wrong many times. The key to survival of roses is similar to other plants. Cease fertilization in July. When cutting roses late in August and onward into the fall, always cut with a short stem to avoid stimulating new soft growth. Some growers recommend removing the foliage from the lower half of the bush in late August to slow growth. Reduce watering beginning September but do not allow the rose bushes to become dry. These procedures will help the roses harden off properly for winter.
Content Provided by Patricia Chenier
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