American Rose Annual, 51: 51-54 (1966)
Hybridizing New Old Roses
Bruce A. Wilson
Pittsburgh, Pennsylvania

ONE of the most fascinating facets of rose growing as a hobby is hybridizing. I had grown roses for the unique beauty for a few years before the hybridizing bug got to me. In 1954, a good friend of mine gave me a few seeds of 'Gruss An Teplitz.' After some refrigeration in a moist medium, one of the seeds sprouted. Three years of watching and waiting passed before that seedling bloomed. I was so sure it would be a world beater, that even before it bloomed it was named "Great Expectations." I've kept that seedling to this day, to remind me of how poor a rose can be. It has no vigor, mildews badly, freezes down to the ground every year, has no fragrance and very poor color. Since this epic occurrence, I have had somewhat better success and through a great deal of luck and a little good management produced a passable rose or two.

Early in the game, about 1957, I realized that it was futile to continue to work the hybrid teas and floribundas. Oh, I could have "lucked" into something, but the odds are very great against it. The few seedlings produced by me were of poor quality and certainly nothing new or different from what had already been produced by others. I decided to leave the lucrative field of modern roses and do some much needed work with the old rose class. The primary objective of my program was to produce a rose with the form of a hybrid tea and the unique characteristic of moss from the Moss Rose, plus any added vigor and hardiness the Moss Rose might add.

One of my first efforts proved to be one of my best. The cross of a Moss Rose, 'L. Gimmard' with the hybrid tea, 'Crimson Glory' was indeed a fortunate choice. The resultant seeds produced ten seedlings which were as varied and different as could be. Out of the ten, only five were good enough to keep. These five (all once bloomers), inherited good vigor, disease resistant, good color and great hardiness. Since these early attempts, I have made many more crosses trying to combine the good qualities of the moss and hybrid tea roses. With partial success with the red color and while continuing to work with the reds, my attention went next to the white and yellow colors. Results in this direction have been somewhat less than spectacular. Although repeated attempts have been made to introduce the hybrid tea shape to the white and yellow Moss Rose, the desired results have not been realized. Many factors account for this. The two white mosses, 'White Bath' and 'Comtesse de Murinais' make poor seed parents because both are so full and tend to a button eye. Both produce some pollen and so, are used as pollen parents. 'White Knight' and 'Snow Bird' are both poor parents and 'Blanche Mallerin' is only a little better. The old reliable, 'Frau Karl Druschki' has proven to be a good seed setter and was used last season to set four fat hips and the seeds break like popcorn. Many attempts have been made to use 'Peace,' 'Eclipse' and 'Gold Cup' in an attempt to improve the yellow class, but once again, the results have not been in direct proportion to the efforts.

One old red moss in my garden seems to be a vigorous pollen parent. This rose was used on some prospective seed parents that heretofore had proven difficult to impregnate and with this pollen, the cross took readily. Large, healthy hips resulted with many seeds. This moss also seems to produce a large percentage of repeating seedlings when selfed. It is hoped that by using it as the pollen parent, this desirable characteristic will be passed on. 'Quatre Saisons Blanc Mousseux' moss is a fascinating rose. The unique beauty of the bloom and the mountain of moss on this one makes it fairly shout, "Look at me!" From the hybridizers' viewpoint, it not only sets seed and produces good pollen, but repeats well too. This fine rose has only recently been introduced into my program, so its effect is yet to be felt. It is hoped that by crossing this rose with a modern rose, the result will be a high-centered white moss rose that repeats well. Some people who may be inclined to try hybridizing in a small way may find it beneficial to follow these few instructions so as to make their venture more rewarding and avoid the pitfalls that trap most beginners.

Pick the hips as soon as they show good color, in the fall. None are left on the bush after the first of December, color or not. The seeds are immediately removed from the hips. Cleaned baby food jars are filled half-full with moist vermiculite. The seeds are placed in a three-inch square piece of white cloth and this placed in the jar on top of the vermiculite. The jar cap with two or three holes punched in it for ventilation is then put on the jar. Place the jar in the bottom of your refregerator.

After two months, weekly inspections are in order. Any sprouted seeds should be planted immediately, removed from the refrigerator and placed where the temperature is no warmer than 70 degrees, to allow the seeds to sprout more rapidly. When sprouting has ceased, replace the seeds in the refrigerator for more after-ripening. The potting soil I use is a mixture of one-third good soil, one-third peat moss and one-third sand. Purify the soil by placing it in a container at least as large as a standard eight-quart pail and mix into it a solution of about two tablespoons to the quart of water, of Phaltan or Captan. This way be used immediately if it is necessary. Using 2 1/2-inch pots, place a few pebbles in the bottom for drainage and fill the pot with the potting soil.

Push a hole in the center of the soil three-quarters of an inch deep and fill this hole with vermiculite. These pots are prepared twenty or thirty at a time, well in advance of the seed breaks. This allows quick planting once a seed sprouts to a quarter of an inch long. When planting time comes, this prepared pot is placed in water up to the rim to soak both the pot and the soil. After the pot and soil are well soaked, place a sprouted seed in the vermiculite. Label the cross, such as 'Crimson Glory' X 'White Bath' and cover the pot with a plastic bag held with a rubber band. The pint-size freezer bags are just the right size for the 2 1/2-inch pot. Place the pots under fluorescent light.

My light setup is quite ordinary. Two 40-watt fluorescent tubes are the main light sources with two 25-watt incandescent lamps adding a little red light for short, stocky growth. An aluminum foil reflector placed over the lamps conserves on light energy. A plastic-lined wooden box about 30" by 60" filled with moist peat moss is used to hold the pots. A pulley system counter-balanced with a gallon paint can filled with stones eases the job of raising and lowering the light source as required.

If the seed breaks by January 31, the seedling will normally be large enough by spring to set out in the garden and make good growth. The seedlings must be hardened off more to the sun than to the outside temperature. Unless the seedlings are exposed to the sun gradually, the leaves will sunburn. The hardening off process is accomplished easily. The entire box of seedlings is placed outside May 15. Shading is done by placing two or three thicknesses of screening over the seedlings for a week or two, gradually remove a layer each week. A wind shield is helpful also, as the fragile seedlings damage easily. After this hardening-off period, the seedlings may be placed in the garden row for normal growth. A full-sized plant will result in about two years with modern roses and about three years with old roses.

Only diseased or dead wood should be removed from the seedlings, as pruning tends to dwarf the plant and in the case of old roses, delay the time of blooming. Also, it is desirous to observe the natural growth habit of the seedling. If the bush and bloom proved encouraging, the plant may be budded on Rosa multiflora rootstock to see how it will do off its own roots, Hybridizing is a fascinating hobby and when one does produce a plant of some merit, there is a real sense of accomplishment and feeling of pride. No matter how many times you anxiously await the next season to see how this season's work turns out, the next season is just as anxiously awaited. Do not expect to produce the desired results the first year. Rather, work for steady improvement and hope for the lucky break.

One closing thought is to above all, keep your roses a hobby. It is possible to make rose growing a chore by trying to grow too many, or in hybridizing, to fire a shotgun blast, so to speak, and end up with more than one can easily handle. This is most discouraging. Concentrate on a few well-thought-out crosses. The temptation is strong to hit everything in sight, once the season gets going. Resist this, and do only what can be done without a great deal of effort. This way, growing and/or hybridizing roses will be a pleasure, not a problem, a joy, not a job.