Quite aside from the enjoyment to be derived, there are several practical advantages. Growing one's own plants affords an economical way of increasing the stocks, even if the varieties already on hand are to be used. It makes possible experimenting with many new or rare varieties not otherwise readily obtainable—the entire world, in fact, becomes your pasturage for new plants of beauty or of interest for the rock garden. And then there is the further advantage—which to me has always seemed to be the most important—that in the more intimate contact necessary with the plants, in propagating them yourself, you come to know their requirements and preferences, their little peccadillos and idiosyncrasies, much more thoroughly —and sympathetically. Most beginners at rock gardening have already had at least some experience with other plants, and with gardening in general. They can, therefore, look forward with the assurance of success to the propagating of a great many of their rock plants if they care to undertake this work. The methods of propagation are, in general, similar to those employed for perennials, i.e., by seeds, by division, by layering, and by cuttings. But a word concerning each of these, as they apply particularly to rock-garden plants, may be of some service.
GROWING FROM SEED
Of the four methods of propagation mentioned, growing from seed is perhaps the most useful, and certainly the most exciting, as each trial with a plant that has not been grown before is a new adventure into a land of mystery, in search of unknown beauty. For what treasures may these little paper packets, come, perhaps, from across oceans and far-away continents, with their magic contents, bring to you:—fairy flowers from the mountains of the world, which neither you nor 5'our friends have ever seen before.
If you are going to try growing seed at all, make up your mind in advance to one thing—that you will make a success of it! And to that end, leave no stone, or necessary forkful of soil, unturned.
The sowing of seed in the open is often suggested; and the readiness with which many of the rock plants seed themselves is cited as evidence to the fact that they may easily be so grown.
Lay not that flattering unction to your soul! Give the seed which you are going to plant every possible chance for making good. And that means providing them, if you do not happen to possess a greenhouse, at least with the protection of some sort of frame.
A Frame for Seed Sowing. A frame is not needed for protection from the cold, as most of these plants are among the hardiest of the hardy.