HOW TO PROPAGATE FLOWERING SHRUBS.
An esteemed member of the Association requests that information may be given on this subject, being desirous of enjoying the pleasure of having flowering shrubs in his grounds, and finding that it is only occasionally that he can succeed in raising those received from the nurseries. In compliance with this request we give the usual methods of propagating some of our most desirable hardy shrubs, in the hope that the information here given may prove both interesting and profitable to many of our readers.
The Japan Quince is one of our shrubs that is very easily propagated by layers, cuttings of the roots, and seeds. The branches should be cut with a tongue, as is usually done in layering, and layered sufficiently deep to be kept moist through the summer, and remain in the ground until the next spring, by which time they will be found to be rooted, when they can be cut loose from the parent shrub and set out as independent plants. The proper time to put down the layers is in spring, as soon as the soil has become somewhat warmed and settled, and before the leaves put forth. It may also be propagated from root cuttings. In order to grow them in this way successfully, it is desirable to prepare a hot-bed sufficiently large to insure a durable, gentle bottom heat. When this has been secured the bed should be covered with about four inches of good, rich, sandy loam, the roots of the shrub cut into pieces about four inches in length, should be thrust into the soil at an oblique angle, so as to be covered about half an inch deep at the upper end, and three inches deep at the lower end, then gently watered with a fine rose, so as to settle the soil well about the cuttings, and the sash kept on day and night until the sprouts have made their appearance above ground, when they should be treated as to heat, air, and moisture in the same way as any tender growth. Care must be taken with the watering before the shoots appear, not to apply so much at any time as to materially reduce the temperature of the soil, or to make it at all sodden. As the young plants increase in strength they should be gradually hardened off, and by mid-summer be enabled to endure the weather without any covering by night or day. They can be taken out of the frame in the fall, and stored in earth in a box in the cellar, and set out the next spring in the open ground. They can also be raised from seed, although there will be more or less variation in the color of the flowers of the seedling plants from that of the parent. The seed should be sown in the fall, in shallow drills, and covered but slightly. In the spring it will germinate, and the young seedlings will require the same care in weeding and cleaning and stirring the soil as a bed of carrots. In the fall they should be taken up, packed in earth, and stored in the cellar until spring, when they should be set out about six inches apart in rows, and cultivated and cared for until large enough to be set in their permanent place on the lawn.
The Plum-leaved Spirea is somewhat more difficult of propagation, though it will root tolerably well from layers, tongued and put down in the usual manner of layering. But the best way to propagate it is from cuttings of the green wood in summer. The most successful plan is to plant the shrub in a box or tub, place it in the greenhouse in February, and gently force it into growth. When the young shoots have begun to harden, they should be taken out and set in pure sand in the propagating bed, over a gentle but steady bottom heat. Here they will soon strike, and when the roots have been well developed may be potted off into small pots and treated like any young, tender, newly potted plant. They may also be grown in the summer from cuttings taken from the shrub in the open ground, and set in sand over a hot-bed having a gentle bottom heat, covered with sash and shaded so as to exclude the sun. Considerable skill and attention are requisite to success in this method of propagation; there is danger on every hand, danger from too much moisture, and danger from too little moisture, danger from keeping the sash shut too close, and danger from admitting too much air, the bottom heat may be too great, or it may be too little, the cuttings may be taken too green, or they may have become too much hardened.
The Chinese Double-flowering Plum is propagated by grafting or budding on stocks of the common plum. It is possible that it might be made to grow from cuttings in bottom heat, but we have never tried that method, the process of budding it upon the plum stock being much more convenient, expeditious, and economical.
The Purple-leaved Filbert is propagated by layering. We have found that in dry and hot seasons the layers do not root freely, and that it is often necessary to allow the layers to remain for two years before separating them from the parent plant.
The Flowering Hawthorns are best and easiest propagated by budding them upon the common White Hawthorn. The buds take readily, unite firmly, and grow rapidly. We have not tried the experiment of budding or grafting these upon our common Wild Thorn; if any of our readers have made trial of this method of propagating them, it would be very interesting to know the result.
Deutzia Gracilis, a small, slender, graceful shrub, producing pure white, bell-shaped flowers in great profusion, is best propagated also by placing a plant in the greenhouse, and setting green wood cuttings in bottom heat, under a bell-glass; though it is quite possible to succeed when the bell-glass is not used.
Deutzia Crenata flore pleno, comes into bloom towards the end of June. It is the most showy of all the Deutzias, bearing its hanging bell-shaped, scalloped blossoms on the shoots of the current season’s growth, throughout the entire length of the shoot. The flowers are very double, pure white, splashed with bright rosy pink on the outside, and literally cover the branches so as nearly to conceal the foliage. This we have cultivated only from green wood cuttings taken from the parent plant in summer and set in a gentle bottom heat. We believe however that it might be grown from hard wood cuttings taken off in the fall and kept in moist sand until March, and then set in the propagating bed of a greenhouse with a gentle bottom heat, and also that it might be possible to grow it from layers in the open ground.
The Syringa, or Mock Orange, is very readily grown from layers; from suckers that spring up around the parent plant; and by dividing the parent plant itself when it has attained to sufficient size.
Weigela Rosea, a free flowering shrub, with showy, tubular flowers, of a light rose color, blooming in June, is very easily propagated from cuttings, in a gentle bottom heat, or even under a sash without bottom heat, in sand; also by layering.
Perhaps these instances will be sufficient to give our readers an idea of the various methods of propagating shrubs. As a rule most of them can be made to grow from layers, keeping them layered two years if necessary; when this method fails, resort must be had to green wood cuttings and bottom heat.
| VOL. I.] | JULY, 1878. | [NO. 7. |