PROPAGATION. 



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CHAPTER XIX. 



PROPAGATION. 



Prorogation by Seed — by Bulbs, Corms, and Tubers 

 — by Division — by Runners — by Suckers — by 

 Layers — by Cuttings — by Leaves — by Roots — by 

 Grafting — by Budding — by Inarching. 



Plants are propagated either from seeds, bulbs, 

 tubers, runners, offsets, suckers, layers, cuttings 

 of stems, roots, or leaves, and by grafting, in- 

 arching, and budding. 



I. — Propagation by Seed. 



This is the most natural mode of reproduction, 

 and the one which is common to almost all plants 

 in their natural state. It is from the seed that 

 the most healthy and vigorous plants are pro- 

 duced, and, generally speaking, it is the most 

 advantageous mode of propagation. Those char- 

 acteristics which cultivators are most interested 

 in, such as colour, size, form, &c, are not always 

 reproduced in the seedlings, especially of those 

 plants which have been modified by cultivation. 

 For instance, the seeds of Ribston Pippin Apple, 

 G-loire de Dijon Rose, and Mrs. Pollock Pelar- 

 gonium could not be relied upon to reproduce 

 the peculiar characters of the parents. Only 

 those plants whose characters are fixed, and 

 that can be propagated from seeds, are to be 

 relied upon to come true. 



In this country the seeds of the native vegeta- 

 tion generally ripen in autumn, but in most cases 

 germination does not take place till spring; yet 

 they mostly fall from the plant in autumn, for 

 were they to hang on, most of them would be 

 injured by being alternately wet and dry, and by 

 exposure to frost. " By an admirable provision of 

 nature, the seeds of our largest trees, as the Oak, 

 Beech, and Chestnut, drop before the fall of the 

 leaves, which then cover them to the depth of 

 some inches. The leaves decay in the course of 

 the winter, and form towards spring a light 

 covering of leaf- mould, highly favourable to 

 vegetation. Small seeds, such as those of the 

 Lime and Ash, do not begin to drop till after 

 the leaves have commenced to fall, and are thus 

 placed at a less depth." From this it may be 

 concluded that seeds have under purely natural 

 conditions a light covering previous to germina- 

 tion. Although the Oak thrives well in strong 

 deep loam, yet, self-sown, the acorns are placed 

 amongst leaf-mould. Hence it may be inferred, 

 that the soil best adapted for the growth of a 

 plant is not always that which should be selected 



for the seeds to be sown in, and that all except 

 large seeds are best sown in fine, light soil, 

 easily permeable to the young roots as well as 

 to the plumule. Large seeds should not be 

 buried much below the surface, whilst small 

 seeds should be covered one-tenth of an inch, 

 and the depth of covering should be increased 

 somewhat in proportion to the size of the 

 seeds. Those of the Bean and Oak may be 

 2 inches deep, the Walnut and Chestnut 3 inches. 

 Seeds sown out-of-doors often require to be 

 buried deeper than is necessary for germination, 

 to protect them from vermin, &c. A good gen- 

 eral rule is to bury all seeds to the depth of 

 their smallest diameter. Thus, some Palm seeds 

 should be an inch below the surface, whilst 

 Begonia, Gloxinia, and other very small seeds 

 should not be covered. 



For successful propagation by seeds several 

 conditions are necessary: — 1. That the seeds have 

 been perfectly ripened. 2. That they have been 

 properly kept till the period of sowing. 3. That 

 they be sown at the proper time. 4. That the 

 sowing be performed in the proper manner. 



1. Perfection and Maturity of Seeds. — The per- 

 fection and maturity of seeds can be generally 

 determined by their external and internal ap- 

 pearance, and in many cases by their specific 

 gravity, their sinking or swimming in water being 

 frequently a good test. Except for convenience it 

 is never advisable to keep seeds dry for a long 

 time. Most seeds germinate readily if sown as 

 soon as ripe; indeed some, such as those of 

 Primulas and Hellebores, are best gathered and 

 sown before they become quite ripe. The seeds 

 of Cyclamen, if sown when fresh, germinate in 

 a few weeks, but if allowed to get dry and hard, 

 they sometimes fail altogether. It is not wise to 

 allow choice plants to bear large crops of seeds. 

 If the seeds have a plump appearance and clear 

 colour, it may be presumed that they are good. 

 If, in a fair sample, the section present a sub- 

 stance of the natural colour, and the rudiments of 

 the radicle be perfect, there is every probability 

 that the stock will germinate under favourable 

 circumstances. Seeds of a plant that sink in 

 water when good are of very doubtful quality 

 when they swim; although in some cases they 

 may grow, and especially when they float at 

 first, but after having been moistened some time, 

 either sink to the bottom, or only below the 

 surface. The microscope in skilful hands will 

 detect perfections and imperfections impercep- 

 tible to the naked eye. But of all others, the 

 surest test is to sow a small quantity under 

 favourable circumstances, and the proportion 



