Roses - Some General Information And Hints On Hybridization
( Originally Published 1914 )
In the climate of the Middle Atlantic States, it is not possible to grow some of the roses which succeed so wonderfully in the south of England and in France. However, there is a vast area in the United States in which all of those more delicate roses may be successfully grown, more particularly in the south-east and southwest; in fact in every part of our great country where there is little frost all these wonderful Teas and Climbing Teas and Noisettes may be successfully cultivated. In addition to which the Hybrid Teas will be found fine for garden cultivation, while the 'Hybrid Tea Climbers and many of the weaker Hybrid Polyantha Climbers will also do well.
In the very coldest climates the best method is to grow in good-sized pots or boxes, and in the autumn when frost comes move to a cellar or building where extreme cold will not penetrate. In the case of a cellar with an earthen floor the pots can be placed beneath the surface. The only thing necessary during the winter is to give the plants several waterings. In the spring the rose pots or boxes should be carried out and again placed beneath the surface of the soil in their old bed and as the rose increases in size a larger pot must be provided. Roses are being grown on the Gulf of St. Lawrence where the temperature reaches forty degrees below zero; they are protected during winter by the device of covering each bush with a small keg, filled with earth. The Hybrid Perpetuals do best in this locality; even the strongest of the Hybrid Teas tried give poor results. In the more moderate climate of the Middle Atlantic States and in approximate temperatures it would be possible to grow many of the more delicate roses with the heaviest winter protection.
One of the best means of protecting roses from the cold and the wind is a good brick or stone wall. It is expensive, but even a low wall will make it possible to grow the smaller Teas, and a four-foot wall would be of great use in protecting low bushes from the heavy winds, while with a six- or eight-foot wall it would be possible to care for the wonderfully blooming Climbing Teas. The tender Cherokee rose is being successfully grown near Philadelphia on the south side of a wall. The ideal exposure would be a wall facing the south or southeast and, as the winter approaches, the climbers could be taken down from their fastenings on the wall and covered over with earth and the smaller roses cut back and heavily covered. In an ideal rose garden, with such a wall completely surrounding it, there would be a great opportunity not only for the proper growing of many of these very beautiful varieties which otherwise one cannot hope to raise, but by utilizing both sides of the wall it would be possible to bring roses into bloom at different times. On the north side only the very hardiest of the climbing roses would do at all well. Wichuraianas and hardy Polyanthas would be roses to try, and if four such roses of the same variety were planted on four different exposures they would come into bloom at various times, thus lengthening the period of bloom.
A difference in soil and situation affects the time of bloom to some extent. A north slope will come in slightly later than a southern exposure; but in colder sections, and particularly in sections where late frost is liable to occur after growth is started, a north slope is a safe exposure. In such a situation the early spring sun will not reach the roses as it would on a southern slope, and they will not be forced into growth only to be killed back afterwards by the late frosts. It has been well proved that high ground will not have as much frost as low, well-sheltered ground, for in the latter the frost will settle in the late spring and cause damage, whereas on the high ground the air will have free access and will not allow the frost to remain, as it seems to do in low-lying ground.
Proximity to the ocean or any large body of water often gives a more even temperature than is found in inland sections. Near the sea coast of New England, where cool summers are encountered, wonderful beauty is shown by many roses.
There is a very interesting list of roses for the locality of Chicago published in "How to Make a Flower Garden," in which Mr. W. C. Egan gives his experience with roses near Jackson Park, Chicago. From the list which he selects it would seem that the hardiest Hybrid Teas would do well there, as his article included with the Hybrid Perpetuals several Hybrid Teas and Teas which are not among our hardiest varieties.
On the Pacific Coast roses do wonderfully well. In Santa Barbara, California, they come into bloom before Christmas, and the growing season there begins after the period of summer drought; what we in the East would call early autumn is, in reality, spring in southern California. Farther north on the Pacific Coast roses are most successful.
Professor R. T. Stevens, of the University of California, in his very excellent article in the American Rose .Annual for 1916, gives the following information which, with the permission of the editor, Mr. McFarland, is quoted verbatim:
"As most people know, roses even in California demand a period of rest if the best results are to be obtained. California winter temperatures are not low enough to produce the necessary degree of dormancy, and the rose bush, if irrigated during the summer, will produce an ordinary grade of bloom more or less throughout the year, depending on the type of rose. On the other hand it will, in most cases, not only fail to furnish the finest blooms, but will soon deteriorate and die prematurely, due to the continual forcing of growth. It has become customary, therefore, to force dormancy upon the plants by withholding water in midsummer, a time when, be-cause of dry weather, few good blooms are produced. Toward the close of the spring crop, or about the first of July, depending on the condition of the soil, water is withheld from the plants until the first of September. They are not allowed to suffer, but made to ripen their wood and recuperate from the strain of the season's bloom.
"During August the plants are gone over and all stubs and weak growth removed, after which a heavy mulch of cow-manure and a liberal amount of water are applied. Irrigation is kept up until the first new bud is blown, when it may be discontinued to allow the wood to ripen for the winter pruning. In this manner an abundant supply of fall bloom is produced, almost equal to that of spring, while at the same time the plants are insured against an early deterioration.
"Heavy pruning is performed in January, at which time the wood of the previous season's growth is well ripened. In early spring the beds are again mulched and the plants sprayed with Bordeaux as a preventive against mildew. After the rains have ceased, the garden is given a thorough cultivation and overhauling, after which little attention is required until the summer rest, except an occasional irrigation, followed by a superficial working of the soil. Under this treatment the first flowers of the spring crop appear in February or early March, and continue until about the first of July.
"The superiority of budded roses is believed to be generally recognized. Some types, especially Teas, are too weak and delicate for ordinary outdoor culture unless worked on a more vigorous root, and the majority seem to be more or less improved when so treated. Budded plants are here not only more vigorous and longer-lived, but are more adaptable to wet and poor soil conditions, and will produce larger and earlier flowers in greater quantity than own-root plants.
"While climbing roses are widely grown in California they are not always exhibited to the best advantage. Too often they are seen covering a residence instead of a structure especially built for such purposes. The possibilities of roses of the Noisette type, used on columns, arbors and pergolas as ornamental gar-den features, are great, while many varieties, as the Cherokees, Gloire des Rosomanes and Agrippina, prove particularly adapted to cover fences and to serve as hedges. Because of the mild climate, climbing roses are apt to greatly overgrow their position and often become unsightly in shape and appearance. Intelligent pruning and thinning are necessary to correct these conditions.
"Roses grow easily and bloom freely in this equable climate, but it is believed much finer and more satisfactory results would originate from a close study by the amateur of the correct culture and treatment of the various types of roses adapted to California, with particular reference to their summer rest."
This chapter would not be complete without further information on the most interesting part of rose growing, that is, hybridization to secure new varieties. The books noted in the chapter on propagation will take the reader very thoroughly through this most fascinating subject, and they should be secured by any one who proposes to attempt such work.
It will be found by the person who wishes to have some interesting work for the winter, and who can give up part of his greenhouse, that a great deal may be accomplished even in a limited space. A conservatory would also give one an opportunity to make interesting experiments.
The Hybrid Tea list, with the addition of Pernet-Ducher's Pernetiana, makes this section of outdoor roses very complete, but there is still a large field to work upon, particularly in the climbing section. Any one who can breed a hardy seedling climber which will bloom reliably from frost to frost will be giving the rose world a most important addition. By securing a few potted plants in the early autumn, quite a number of crosses could be made, although the chances of securing what is desired would not be as great as if one had more plants with which to experiment.
As most of the books state, a rose will become fertilized with its own pollen more quickly than by the pollen of any other rose. The main point for success is to watch most carefully the rose which is to be bred so that before the pollen becomes ripe the anthers and stamens may be removed. It is very easy to tell when the pollen is ripe because it will then drop in small yellow particles upon the petals of the rose, and if one's finger is rubbed across the anthers the yellow dust will at once be noticed. Pluck off the petals of the selected rose before the pollen reaches this stage. After the petals have been removed a small pair of scissors should be used to cut off the anthers. As this is done turn the rose and only take off the stamens from the under side, thus precluding any possibility of the immature pollen reaching the pistils. Some few of them will be bent over and not yet fully developed, and these should be carefully removed from the plant because later on they will be dangerous to the experiment. The pollen contained on such anthers if kept in the sun will be developed and can be used on any other flower. Having prepared the seed parent or female flower, now secure the pollen from the other parent selected. If the plant from which the pollen is taken is not needed for a seed parent, it will be unnecessary to secure the pollen as above suggested, but the whole flower may be cut.
All authorities agree that a bright, warm day is the best on which to breed roses, as in damp, cloudy weather the pollen is not active. When the pollen is falling from the anthers in small, yellow dust, your rose will be properly fertilized, it being only necessary to shake the pollen on to the pistils of the rose selected as a seed parent for the hybridizing to be complete.
After roses have been hybridized, allow the seed pods to develop, and when the weather becomes warm in late spring or early summer take the plants from the greenhouse or conservatory and plant the pots in soil out-of-doors to enable the heps to mature properly. In order to protect seed pods from birds or other interference it is advisable to cover the hybridized plants with wire netting. Towards early autumn the seeds should be taken carefully from the heps and planted, each lot being kept separate.
In mature seeds a little rose plant will sprout in a month or thereabouts with greenhouse care, bottom heat, and carefully-selected soil for germination. In the course of another six weeks very small blooms will appear on many of them, with the exception of the climbers.
Commercial firms who grow new varieties of out-door roses at once bud or graft on Manetti or Briar stocks to propagate the wood.
As a rule, inside grafting is not done the latter part of the winter, the sun being too hot.
Briar as a stock is not used in indoor work, as during the winter it "goes to sleep."
For these reasons seedlings of Wichuraiana, of Rugosa and of sorts which grow especially well on their own roots should first be tested on their own roots.
For a temporary inside test, budding on strong blooming plants will be found to give quick results.
After a satisfactory test, the surest and best method to increase the stock is to bud the varieties outside the following August. The plant is then ready for the outdoor ordeal if it is to be used as a garden variety. It will thus be seen how much time is required before a new variety may be passed upon as of value.
In experiments with cuttings and with budding it was found that while the information contained in the text books on these subjects seemed very complete, work was not successful until instruction was received from men who did this work themselves. Cuttings are so generally used in greenhouse work that it is easy for anyone who wishes to make them to learn at first hand how the operation is accomplished; but they are only valuable for the hardiest varieties.
Budding is more difficult, and it is doubtful whether it would pay the average amateur. Those who desire to bud on a large scale should buy the books previously referred to, in which the descriptions are most accurate and thorough, but they should also take a lesson from some practical budder.
The disadvantage of budding is the length of time required to secure results. It is necessary in the fall to procure seeds of the stock to be used. There is then the work of planting these seeds in February, taking care of the young seedlings, and setting them out in nursery rows as soon as the weather is suitable. Such seedlings are ready for budding in August of the same year. After they have been budded they are ordinarily left until the following spring when, if the bud takes, flowers will be produced. These plants can be moved only in the spring at great risk, and should be carried over in the nursery beds until the fall, when they may be moved. It therefore takes a year from the time the seed is gathered before the budded plant may be placed in its garden bed. Other methods are to procure plants or cuttings of the stock desired, place them in nursery rows in the fall or following spring, and bud them likewise in August, after which time the procedure is the same.
On the other hand, with the majority of field-grown, budded stock selling at an average of fifty cents apiece, the amateur may secure his plants in one fall and have bloom the following spring, thereby saving a year.
A quicker method, but which requires the use of a greenhouse, is to have the stocks budded in August, and in the fall when the plants become dormant, pot and give greenhouse care during the winter. Such plants are put out in the spring after the season is settled, and by this method blooms on new varieties and tests of new seedlings are quickly secured. The disadvantages are: First, the great amount of care necessitated by the greenhouse; and second, the fact that after the plants are removed to the garden beds they have already had a considerable period of growth and their constitutions are impaired by the lengthened outdoor season before dormancy again prevails in the fall.
All this work, however, is most interesting for those who desire to go into rose growing to the fullest extent. There is one point, not generally mentioned in the books on budding, which seems to be worth recording. Most handbooks advise that after the bud is cut, the wood be removed from the bark and only the bark with the small immature bud left. This result is obtained by a quick short jerk which severs the weak and immature bud from the hard wood of the cane. This was found most difficult to accomplish, as unless the plant was in exactly the right condition, the immature bud was often broken. The men who taught budding did not use this method, but after cutting the bud, shaved the same down until there was only a very small portion of wood left with a large surface of bark. In this shaving down, the point emphasized was that the edges should be as clean as possible. This explanation will be understood in conjunction with any book on budding.
Where a grower is unable to procure additional plants of a particular rose it is suggested that he send wood of the variety to the nearest nurseryman, who can bud it for him.
For those who wish to grow roses for exhibition, the method has generally been to bud in August and cut the flowers in the following spring from the budded growth, as the first or maiden bloom on such plants is usually finer than that on two- and three year-old bushes.