Canadian Rose Annual pp. 80-81 (1956)
Recent Development in Shrub Roses
By WILHELM KORDES

EDITOR'S NOTE
The name of Herr Kordes has long been well and favourably known wherever Roses are grown. His accomplishments as a hybridizer of outstanding Hybrid Teas and Floribundas have won universal acclaim but he has also been engaged in patient efforts to produce hardy, disease resistant and recurrent blooming shrub Roses. In recognition of the increasing popularity of the latter group we invited Herr Kordes to favour us by writing a brief outline of his work and he has kindly acceded to our request The information furnished herein could not come from a higher source and we are indeed grateful to our distinguished German friend.

When your garden is in a country where hard or sudden winters are not allowing the tender roses to grow and bloom-you do have to look for hardy forms that may fill your wishes for Roses. We had really hardy, frost resisting Roses, in the old gallica, centifolia, moss and damascena groups, but with the coming of the perpetual Asian species the hardiness became a neglected factor in breeding work and breeders especially those in southern countries never cared whether or not their roses could be grown where the thermometer went below zero.

It is now over thirty years that I have tried to get big bush roses that would stand our winters-severe winters at that. No frost up to Christmas and then sudden hard freezing and bitter eastern winds-on a bare soil. Last winter the cold was so prolonged and hard, with lots of snow, that the wild rabbits died of starvation and cold.

I first tried to get all the hardiness from the H.P.s—but this was soon found out to be a mistake. Then I tried the old hardy spinosissima and especially the form altaica. Herewith I had fair results in the once-flowering bush forms—they did grow, flower, without the slightest bit of frost damage and, what I consider most important, no blackspot. Strangely the repeat-flowering forms did all have black spot in a destructive way and after at lease ten generations I have only a few of these perpetual flowering forms that are resistant to the worst of all fungus diseases, black spot. What I liked so much on them was their delicious scent—I know of no other roses that have the marvellous scent some of these perpetual forms have. Maybe success is near but it has taken thirty years to get a sound plant.

This second trouble, the resistance against this pest, was not included from the beginning of my breeding experiments—I wanted hardy Roses, hardy as rugosa but I never tried rugosa except the variety 'Schneezwerg' a rugosa-polyantha hybrid. No hardy roses came out of it, all had long semi-climbing shoots and the flowers were at least very mediocre. So I gave that up. Then I tried the sweet briar hybrids of Lord Penzance and from these I soon had fine, big, bushy plants, some very frost resistant, some less so but all the bigger plants only June flowering. That was not quite what I wanted. Some of these have been sent out and are now selling well, because they have large flowers, are a good colour and hardy. The perpetual forms did not come until after a number of years that never brought but once flowering forms. After the first success I had some every year and now these Floribunda type sweet briars are selling well, they are free, fairly resistant against black spot, and winter hardy.

However, the best of the results was a pure bit of luck. Old Max Graf seldom gives seed, the pollen is, at least here, useless, and from a plant that had been standing against a wall for many years I got a few seeds and the one Rose I wanted, a perfectly hardy climber, or better a creeper that was at the same time black spot proof.

This rosa kordesii was fertile; seeds were produced in abundance and from its seedlings I soon had a fair lot of perpetual forms that are today, the great craze in Germany. We never expected a run like the one we experienced last autumn with these new, perpetual kordesii climbers. Old plants never sprayed and grown without protection do bear a tremendous lot of flowers and further intermittent crops until frost stops them. A little bit of good luck is more than a brain full of knowledge. There is no getting away from this fact; the rosa kordesii proves it.