5° 



THE FLOWER GROWER'S GUIDE. 



Other materials occasionally recommended are Tufa, a volcanic substance used for 

 mixing with the compost for various species ; leaf soil, which should be only partly 

 decayed, and used in conjunction with peat for some of the stronger-growing kinds ; 

 and polypodium fibre — the roots of the wild polypodium vulgare — is sometimes used 

 for potting odontoglossums and other dwarf orchids. It would be a pity were it to 

 become generally used, as it would mean the rapid extinction of one of our most 

 interesting ferns, and besides, it is not in any way superior to fibrous peat of good 

 quality. 



PBOPAGATION. 



The propagation of orchids is usually a slow and uncertain process, especially in 

 the hands of inexperienced cultivators. Some kinds of orchids can be freely divided, 

 and the young plants grown with ease ; others may be grown for many years before 

 any stock of a particular variety can be obtained. All the vandas, aerides, saccolabiums, 

 angrsecums, and similar kinds, grow from a central stem, but occasionally push young 

 growths from the base. The latter may be taken off when a few roots have formed and 

 set going on their own account. The tops of such plants, too, are sometimes taken off 

 below the first tier of roots, and potted or basketed. 



Barkerias, cattleyas, calanthes, ccelogynes, cymbidiums, laelias, odontoglossums, 

 oncidiums, in fact the general run of pseudo-bulbous orchids, can only be propagated by 

 division. See that every divided portion has a few roots, and one or more young 

 growths (leads), and, if possible, sever the pieces some time before potting them 

 separately. 



The long-stemmed section of dendrobiums, including D. nobile, D. crassinode, 

 D. devonianum, D. pierardi, and many others, often produce young plants at the ends of 

 the stems, which may be taken off after a season's growth on the parent plant, as shown 

 at the dotted line in Fig. 22. If a more rapid mode is needed, cut off the stems and 

 lay them on sphagnum moss in boxes or pans, when many buds will produce plants, these 

 being taken off, and potted separately, when roots show at the base. Cypripediums are 

 propagated by dividing into as many pieces as required, these orchids being among the 

 easiest of all to increase. 



For thunias a rapid mode is to cut the old stems into lengths of about 4 inches or 

 6 inches, and insert them in pots of peat and moss over good drainage, placing the pots 

 over a brisk bottom heat until young roots and growths appear. Skilful cultivators 



