Southward from our location in the far north province of Saskatchewan, tender roses of the hybrid tea, floribunda, and other classes are often filled up with earth for winter protection.
Here in the North, the method does not function well, and we have worked out alternative, more reliable methods.
Tins raise the question of whether our methods would not be good for roses growing south of us.
Hilling up often fails here because the rose bark is still green and tends to rot when hilled.
Successful Method In Prairie Provinces
Sometimes this happens when an organic mulch is placed in contact with the bark. Our winters come so suddenly that the bark has less time to mature.
Also, when a plant is mounted over snow lodges between the protruding mounds and funnels the cold down into the plant roots.
Soil has some insulation value, of course, but not nearly so much as snow’. In windy areas snow is not a dependable mulch.
A successful method for rose here in the prairie provinces is to plant the point of union 4” to 6” inches below ground.
Rose Bark Planting
Plants are often set semirecumbent to avoid placing the roots too far into the subsoil. Rose bark is usually mature enough by spring to be placed in moist soil without danger.
With deep planting, if the roses die back to ground level, they come up in spring from an eye above the point of the union—not below it.
Thus the named variety is preserved, and the rose does not “turn wild,” indicating that the understock alone is alive.
I have had rose plants kill back to 4” inches below the ground line and come true to name the following year.
When they are killed back that far, they are severely weakened and come up late and weakly.
An objection to deep planting is that it stimulates own-rooting and that the own roots of Hybrid Teas are more tender than the roots of Multiflora understock.
This is often true. However, in Saskatchewan, the Multiflora roots are so tender it makes little difference whether or not they are replaced or supplemented by their roots.
The ground must be mulched with straw, slough-hay, or some such material to a depth of two feet above and four feet or more on all sides of the plant to protect the roots.
Or, you may dig up some of the unrooted rose branches, bring them indoors, and pot them. They will remain dormant for a while if put in an ordinary root cellar.
When they start to grow vigorously, they may be brought up to a house window and kept growing until spring. Then if the original plant dies, you have not lost everything.
It is a pity hardier under-stocks are not used for tender roses sold in Canada’s prairie provinces and the adjacent states.
A hardy understock ceases activity early in fall and tends to make the plant bud on it cease activity earlier than otherwise.
This encourages the maturity of wood which is important for survival over winter.
Grafting Wild Roses
Occasionally, however, an enthusiastic rose grower will graft his plants. In 1910, George Bell, who homesteaded in the Vilna district of Northern Alberta, acquired scions of Hybrid Perpetuals.
He cut the tops off some wild roses in his farmyard (probably R. acicularis, the Arctic rose) to the ground and grafted the scions upon them.
Each fall, he cut the plants back to about a foot and covered them with a foot of dry sawdust held in a box without a top or bottom.
Over each box, a waterproof sheet was placed to keep the sawdust dry.
I have kept in touch with Mr. Bell since 1932, and when I last heard from him in 1952, the original Hybrid Perpetual plants were still alive.
It is difficult to say if this was due to their hardy understocks, excellent protection, or both.
They would have winter-killed early if either factor had been absent. In any case, the importance of hardy understocks for tender roses is firmly underscored.
44659 by Percy H. Wright