174 ORCHIDS: HOW TO GROW THEM SUCCESSFULLY. 



A. G-., LIVERPOOL, asks : What is the proper treatment of Oncidium 

 Lanceanum ? Mine are in the Warm house, but fail to grow satisfactorily, and 

 the leaves are covered with black spots as in foliage I enclose. 



REPLY. This species seems peculiarly liable to this kind of spot, and 

 greatly disfigures the handsome foliage. It is one of those Orchids which grow 

 freely when placed in the right position. This spot is no doubt caused by a 

 superabundance of moisture. It is a Hot-house Orchid, but should not be grown 

 in that house regardless of position. It should be remembered that it belongs 

 to the stout-leaved section, and on that account can endure a good deal of 

 dryness in the atmosphere. A position which is dry and exposed to the light 

 should be selected for it during winter, taking care not to over- water it. In 

 summer it succeeds well if suspended with the Warm-house Dendrobiums. 



A CORRESPONDENT, Gr. W. B., KENT, asks six questions, as follows, with 

 my reply to each : 



]. What are the general coaditions of growth of an Orchid that should 

 decide the cultivator whether a species should by preference be basketed or 

 potted, besides the fact of its liking to be near the glass, or not ? 



REPLY. Orchids which really do best in pots or pans are those whose 

 roots will not grow if exposed, unless the air is charged with an excess of 

 moisture. The roots of Cypripediums, Odontoglossums, and similar kinds, 

 generally make but little progress until they get beneath the compost, and 

 when once there they show no inclination to reappear on the surface. On the 

 other hand, Orchids whose roots show no special preference to hide themselves, 

 and grow rapidly until coming into contact with some object upon which they 

 speedily take a firm hold, are best with basket culture. Amongst the latter 

 may be named Cattleyas, Lselias, Phalsenopsis, Aerides, &c., but there are 

 exceptions to every rule. Such tall growing kinds as some of the Aerides. 

 Vandas, Saccolabiums, and Angraecums ; some of the Lselias also, such as 

 purpurata, and varieties of elegans, harpophylla, cinnabarina ; also the tall 

 growing Cattleyas, such as the guttata varieties, and Harrisonise, intermedia, 

 and some of the labiata varieties, which are tall and heavy. Then there are 

 also many tall growing Dendrobiums and others which could be mentioned, all 

 belonging to the section of aerial rooting Orchids, which require to be placed on 

 the stage owing to their great height. Pots are more convenient and answer 

 the purpose better than baskets, for they are cheaper and answer equally well. 

 Then any aerial roots which may penetrate the compost are more secure from 

 the ravages of the various pests to be found amongst the plants. There are 

 many Orchids which are suspended in baskets or shallow pans, simply becau&e 

 they are dwarf growing, and are thus brought nearer the light, such for instance 

 as the small growing Masdevallias, Oncidiums, and Odontoglossums, the 

 Pleiones, Sophronitis grandiflora, &c. 



2. In repotting plants that have not appreciably increased in size, is it 

 preferable to clean away the old material and pot up in the same size pot with 

 fresh stuff, or to allow the old ball to remain and increase the size of pot ? 



REPLY. In repotting Orchids never allow the old ball to remain intact. 

 Only one thing can possibly be worse, and that is allowing the old pot to be 

 placed into a larger one and covered with new compost. I have seen this 



