All too often, the rose catalogs use the word “hardy” to describe roses that cannot survive the average northern winter without careful protection. Unfortunately, this is likely why many gardeners decide they cannot grow them.
They buy rose plants described as hardy, then the plants die the first winter, and so the conclusion is that in their area, roses are “impossible.” Of course, hardiness is relative. Moreover, quality varies considerably with location.
Perhaps we should not accuse the rose grower of intentional misrepresentation when he describes some variety as hardy, which is only hardy in a northern locality when properly prof elected.
I believe that using the words “hardy with protection” instead of “hardy” in such cases would ultimately increase the growth of roses in all our northern states.
Surely a brief note on how to protect roses by throwing a couple of shovels of soil over each plant would not discourage any rose lover from growing them.
Indeed, it would circumvent many a future disappointment.
Factors Affecting Hardiness
The ability to withstand severe winter conditions depends on genetic and external factors.
The former is “in the variety,” while the latter is influenced by the state of the plant as winter approaches, the location in which it is planted, and the protection afforded it.
A rose bush may be compared to a hibernating animal that fattens during the late summer in preparation for long winter sleep. The leaves are the fattening agent of the plant.
Therefore, to prevent severe winter injury or loss, we must be sure that the fall foliage is retained in good condition for as long as possible.
Another factor that influences the hardiness of a variety is the condition of the wood in the fall.
When Weather Changes
If the autumn is dry and if cold weather approaches gradually, the chances of survival are more significant than if there are heavy rainfall and warm days to cause late growth that will not have time to mature before severe weather sets in late summer feeding is also conducive to immature wood at the beginning of winter.
Early growth should be encouraged, and late development should be discouraged.
Fertilizing, watering, heavy pruning, and cultivation stimulate growth.
After July, therefore, the blooms should be cut with short stems, fertilizer should be withheld entirely, and watering and cultivation should be held to a minimum.
If the bed has been mulched, it will be found that both watering (except in extreme instances) and cultivation are unnecessary.
Atmospheric conditions may aggravate or lessen the effect of cold, as registered by the thermometer.
A long cold spell is more damaging than a short one, and continuous cold winds from the same direction are deadlier than “still” cold.
Winter sun also causes considerable injury to the eaves.
It is, therefore, not safe to assume that the hardiness of a variety is to be measured by the mean temperature of the area in which it is grown.
Snow covering plays an integral part in winter protection.
A combination not hardy in the 1111 area where snowfall usually is light could quite possibly survive in a colder climate where heavy snows ea n be depended upon to cover the plant almost all winter.
If roses are planted to the lee side of a hedge, away from the direction of the prevailing winds, the snow will drift in and increase the depth of the covering.
Drainage For Rose Bed
Adequate drainage of the rose bed is also essential. Although roses like and demand a considerable amount of moisture, they will not thrive during tire summer nor survive the winter in waterlogged soil.
Practically all the popular but tender Hybrid Tea roses can be wintered successfully in any part of the United States if the preceding facts are recognized, and adequate winter protection is given.
The safest and most straightforward method of guaranteeing survival is to cover each plant with a mound of the earth after a few heavy touches of frost have ripened the wood. Suppose additional insurance against winter injury is desired.
After they are frozen, the banks may be covered with straw, leaves, corn stalks, or any other material that will shade them and thereby prevent alternate thawing and freezing.
The height of the mound should be at least 6” inches, but it may be considerably higher if the ambition of the person applying it dictates.
The greater the height, the better, for in many sections, the canes will freeze back to the top of the mound, and the higher the bank, the greater the amount of wood retained.
Actually, it is advisable to figure on 10” inches or even more in our northern states.
Covering Climbers For Protection
Tender and semi-tender climbers may be laid on the ground and covered with any material that will hold them in close contact with the earth and prevent them front being subjected to winter sun and winds.
I have successfully wintered many tender climbers without loss of wood by covering them, on the ground, with roofing paper alone.
It has been said that a hybrid’s hardiness ranges from that of both its parents.
Theoretically, we might assume that the older Hybrid Tea varieties would show no winter injury at a temperature of 1° degrees Fahrenheit since one of their parents (the Hybrid Perpetual) is reasonably hardy at 5° degrees Fahrenheit below zero.
The other (the Tea rose) shows sonic injury at temperatures lower than 32° degrees Fahrenheit. There are, however, numerous exceptions to this rule.
The original Hybrid Teas do, as a matter of feet, show slight injury at 10° degrees Fahrenheit.
But in their efforts to obtain greater floriferousness and a more comprehensive range of colors, hybridists have added more Tea blood. As a result, the more recent varieties show greater susceptibility to cold.
We might suppose that Hybrid Tens of the Pernetiana class would be hardier than other H.T.s since they were derived by crossing a Hybrid Perpetual with the Persian Yellow (a species that has shown no injury at 20° degrees Fahrenheit below zero in my garden).
In some instances, this is true, but as a whole, they are even less hardy, probably because the foliage is weak and very susceptible to disease.
Roses Growing In The Arctic Circle
Several members of the genus Rosa have been found growing happily near and even north of the Arctic circle.
While these roses may never be the progenitors of roses that have the ever-blooming qualities of the Hybrid Teas, their offspring may be able to withstand the severity of our winters without protection and have a high standard of blooming capacity.
We can at least hope that extreme hardiness and floriferousness will be combined someday.
Until that day arrives, we must either protect our tender roses or plant only those that can survive without protection.
There are several beautiful roses in this latter group.
I will list a few that withstood a minimum of 20° degrees Fahrenheit below zero in my garden without protection or the benefit of snow cover.
Detailed descriptions of most of them can be found in catalogs and rose books.
The Rugosa and Hybrid Rugosa group as a whole is quite hardy and also recurrent blooming.
The most interesting of these, in my opinion, is the Grootendorst roses which will give continuous bloom until late autumn if the carnation-like blossoms are clipped off as they fade.
Grootendorst Supreme, F.J. Grootendorst, and Pink Grootendorst are the varieties referred to.
Others that deserve consideration are:
- Agnes
- Amelie Gra vera UX
- Belle Poitevine
- Blanc Double de Coubert
- Conrad Ferdinand Meyer
- Dr. E. M. Mills
- Dr. Eekener (sometimes not too hardy)
- Hansa
- George Will
- Golden King
- Nova Zembla
- Rose a Parfum de l’Hay
- Sarah Van Fleet
- Schneezwerg
- Sir. Thomas Lipton
- Stella Polaris
- Turkey’s Rugosa Samling
- Vanguard
A few of these may show some injury during a severe winter, but none will be killed outright by low temperatures, and all will “come back” and bloom the following summer.
Practically all Centifolias, Gallienus, Damasks, Albas, and Spinosissimas, are sufficiently hardy, but few will bloom more than once during the season.
Harison’s Yellow, Rosa altaica, and most of the species roses are in the same category, but their one burst of bloom more OHM justifies the space they occupy.
Recurrent Rose Bloomers
Stanwell Perpetual, blush., Karl Forster, snow white, and Mabelle Stearns, peach pink, are three “must haves” for the rose lover who wants to continue” bloom with minimal effort.
All are recurrent blooming and require no winter protection.
Stanwell Perpetual is an old member of the Spinosissinm family that has retained its well-deserved popularity for generations.
Karl Forster is a great white rose that should be in every garden. It aroused more significant interest in my garden last summer than any alter variety, and horticulturalists are finally awakening to its merit.
A newer variety, Michelle Stearns, is the perfect rose for the individual who desires high-quality and well-colored pink blooms in large quantities on a healthy, vigorous, and hardy plant.
Few Hybrid Teas can surpass its attractiveness, and it is sufficiently hard to survive without protection, most of the time in the United States.
What more can we ask of a rose?
44659 by R. E. Shepherd