THE POTTING AND BASKETING PROCESS
We are often asked what season is the best for potting and basketing Orchids. Experienced growers say that, with the exception of the winter season, they are engaged in potting operations all the year round, potting each section as it requires it. Springtime is a period when a general overhaul of the plants is usual, and, at that time, plants requiring it should be repotted, but those which are not in the proper condition, or which are showing flower-spikes, should be allowed to remain until their flowering time has passed.
As a general rule, it may be said that the best time to perform the operation is soon after the flowering season has passed, and that no plant should be repotted unless it really requires it; but any plant which has become in a bad condition in the pot by being in unsuitable material should be repotted at once, no matter what season it may be.
Care should be taken to use the pots and crocks in a thoroughly clean condition. Broken crocks are generally used for drainage, although they are not now placed in the pots to the depth of one-half or more, as they used to be. The depth of the crocks varies from about one-third in Cypripediums and terrestrial Orchids generally, to a rather greater depth for Cattleyas, Lælias, and similar Orchids, the depth of crocks also being varied according to the density of the material used, fewer crocks being necessary when a mixture of Osmunda fibre, or other material which lets the water through quickly, is employed in place of peat.
Sand and crushed crocks or potsherds are used by many for mixing with the potting material, but they may easily be dispensed with, or used only in very small quantities.
Turfy loam carefully broken up and mixed in suitable proportions with peat and Sphagnum-moss, or Osmunda, or Polypodium fibre, is necessary for Cypripediums, the proportion of loam being greatest for the stronger-growing plants; certain Selenipediums and Cypripediums require quite one-half of that ingredient. Some good growers use loam fibre with a sprinkling of leaves and broken crocks entirely for Cypripedium insigne and others of the green-leafed class, and also for Calanthes, Phaius, Zygopetalums, and other plants.
In preparing the peat for use in potting, the bracken rhizomes should be set aside to place as a layer over the crocks, with a little Sphagnum-moss. Bracken rhizomes have been used with advantage instead of crocks to form drainage for Odontoglossums, and some growers like it so much for that purpose that the horticultural sundriesmen supply it sterilised in bags.
The methods of potting and choice of material vary with different growers, each pursuing in some matters different methods to those observed by others. It is desirable that an Orchid grower should endeavour to find out the best methods for his own circumstances and, if the results are satisfactory, that he should adhere to them, for there is no more prolific cause of failure than in continually trying experiments recommended by others. The operation of potting or basketing Orchids is very simple, and can be readily learned by observation. The aim should be to avoid injuring the living roots but to leave the plant firm in the pot.
PLATE III
DENDROBIUM WARDIANUM
(At the time the photograph was taken this plant bore 264 flowers.)