PROPAGATION 



PROPAGATION OF BULBOUS AND TUBEROUS 

 PLANTS 



Of the many methods of propagation known to gardeners, all 

 except three — budding, grafting, and layering — are practised in 

 connection with increasing the stock of bulbous, tuberous, and 

 rhizomatous plants. Being all herbaceous in character, such methods 

 as budding, grafting, and layering are not generally applicable, being 

 reserved for woody plants. Occasionally Dahlias may be grafted on 

 to the tuberous roots, and the tuberous roots of herbaceous Pseonies 

 are often used as stocks on which the fibrous-rooted Tree or Moutan 

 Pseonies are grafted. With these exceptions, however, the great 

 bulk of bulbous and tuberous plants are increased by other methods. 

 The principal of these are: — (1) Offsets; (2) Spawn or Cloves; (3) 

 Scales ; (4) Bulbils ; (5) Division of the root-stock ; (6) Cuttings ; 

 and (7) Seeds. It may be well to say something about each of these 

 methods of propagation. 



OFFSETS. — By far the greater number of plants having true 

 bulbs and corms, and also most tuberous-rooted plants, are propagated 

 by means of "offsets," which are produced in greater or less 

 numbers from the old stocks. In such genera as Anemone, Aconitum, 

 Chionodoxa, Colchicum, Crocosma, Doronicum, Fritillaria, Galanthus, 

 Gladiolus, Hyacinthus, Leucojum, Lilium, Montbretia, Muscari, 

 Narcissus, Ornithogalum, Oxalis, Scilla, Tritonia, Tulipa, etc., the 

 parent bulbs or tubers produce offsets freely. When it becomes 

 necessary to increase the stock, the old plants are lifted, usually 

 in the dormant season, or just before growth recommences, and the 

 offsets are detached from them. In all cases the offsets may be 

 looked upon as vegetative growths or children representative of the 

 vigour of the parent plant. They arise from the superabundance of 

 nourishment elaborated from the soil and air by the healthy leaf- 

 action of their parents. The original bulb, corm, or tuber being 

 unable by itself to retain all the food sent down by the leaves, is 

 necessarily compelled to build as it were separate annexes to 

 accommodate the surplus material. In this way " offsets " arise, and 

 if not interfered with, will in due course carry out the same 

 principles of growth as their parents. This explains the way in 

 which a few bulbs, corms, or tubers will in the course of a few years 



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