This section is from "The Horticulturist, And Journal Of Rural Art And Rural Taste", by P. Barry, A. J. Downing, J. Jay Smith, Peter B. Mead, F. W. Woodward, Henry T. Williams. Also available from Amazon: Horticulturist and Journal of Rural Art and Rural Taste.
A fine hardy or half-hardy shrub, with large oblong-obovate leaves silvery beneath, and dense heads of flowers, pale rose color in the bud, changing to cream color and white. Sikkim Himalaya.
A desirable neat-growing shrub, with ovate-lanceolate leaves, more or less hairy, and heads of moderate size, primrose colored flowers. Bbotan.
A charming hardy evergreen shrub, producing large heads of brilliant flowers, in which the centre is white and the border lively rose color. A Belgian variety.
The most magnificent of the Indian Rhododendrons, as far as yet known. It forms an evergreen shrub with large broad veiny leaves, stems terminating in a colossal corymb of large white blossoms, which are about six inches in diameter, and nearly as much in length, stained at the base of the cup with pale orange, very fragrant. Bhotan.
Success in Rhododendron culture undoubtedly depends mainly upon the soil in which the plants are grown. Not that other circumstances are unimportant, or to be lightly regarded as items in the sum total of success; but a suitable soil being of primary consideration, the remaining conditions must be contingent on that. In general very erroneous opinions prevail as regards soil for Rhododendrons, and plants of analogous constitution and requirements. Possessors of gardens where the soil is naturally unsuitable for them, often lament their inability to combat that difficulty. Yet nothing is easier. The materials for a Rhododendron soil, to speak familiarly, lie at every man's door - certainly in the rubbish yard of his garden. Decayed vegetable matter in a highly comminuted state is the great indispensable; and, possessing this, which every one having a garden does in some form or other, the chief difficulty is overcome. Wherever the refuse of a garden has for years been allowed to accumulate is this decaying vegetable matter to be found, which, when mixed with a portion of sand or sandy loam, will grow Rhododendrons to perfection. Perhaps the most familiar form in which such vegetable matter is known is as leaf mould, and when that can be obtained it is to be preferred to any other.
Two parts of this, with one of light loam and one of sand (white if it can be had), will form a compost for Rhododendrons which will leave nothing to be desired. Shade and coolness should be secured as much as possible - not that degree of shade which by permanently intercepting sunlight and air would inevitably induce weak and immature growths, to the destruction of the main end in view, flowers - but such grateful and partial shade as would at once temper heat and husband moisture. No shade is so grateful to the Rhododendron as that produced by trees. Yet they should not overhang the plants, but be-sufficiently near to shade, without actually obstructing light.
The rhododendrons, or rose bay as sometimes called, are a class of broad-leaved evergreen shrubs of exceeding beauty both in foliage and flower. Like the kalmia, they succeed best when grown in soil composed mostly of vegetable loam and sand, although some cultivators advise free use of well-rotted animal manures. Such application we have found to produce free growth, but at expense of hardihood, and when necessary to improve the soil, advise fresh woods loam rather than animal manure. The varieties maximum and catawbiense have been tested as to hardihood all over the Union, and everywhere proved successful. Many others are probably equally hardy when grown under the same circumstances; but a large proportion of those sold from year to year are imported plants, and in getting acclimated too often die. We consider the great secret in growing rhododendrons successfully consists in keeping the soil cool and moist, and this is best done by surface dressing of light half-decayed leaves a depth of three or four inches over the soil in which the roots are growing.
Fig. 64. - Rhododendron.
A free use in planting of kalmias and rhododendrons in the small yards and gardens of our suburban residences would give to them a cheerful living brightness in winter, and add largely to their beauty at all seasons.
We have several native species of the rhododendron, all of which are beautiful shrubs, and well worthy of cultivation. They were, long ago, sent to Europe, where, through the skill of the gardeners of the Old World, hundreds of new varieties have been produced, many of which far excel the original species. There are also many species natives of the Eastern Hemisphere, and new-ones are being constantly discovered. Hybrids in great number have also been produced, not only between the different foreign species, but those of our own country, until it is quite certain that no genus of evergreen shrubs can at all compare with the rhododendron for handsome foliage and gorgeous flowers. Many of the foreign varieties and species are not hardy in the Northern States, but there is a sufficient number to satisfy the most ardent admirer of this class of plants. It requires experience with each kind to determine its character, therefore one must import many to find a few that are suited to the climate; and the high price at which all new sorts are sold, prevents the majority of our nurserymen from testing them.
There are, however, a few of our larger establishments that have expended thousands of dollars in testing the various species and varieties of rhododendrons ; and they now offer to the public the benefit of their labors in lists of sorts which have proved to be perfectly hardy and reliable. We would advise those who want rhododendrons - and who does not ? - to examine the catalogues of these nurserymen. There are so few nurserymen who make a specialty of this class of plants, that we shall take the liberty of naming two firms whose stock we have lately examined, and think it worthy of a special notice. We refer to Parsons & Co., Flushing, N. Y., and Hovey & Co., Boston.