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.)
BASKETS AND POTS
It is more in accordance with nature to grow epiphytal Orchids of convenient size in baskets to be suspended from the roof of the Orchid house, and in the case of subjects reputedly difficult to grow the best results are often attained in this way. At the same time, this is due as much to the plants being placed near to the glass of the roof, as to the fact that the air has better access to the roots than when the plants are in pots. Hence it is that for suspending plants of small and medium growth, Orchid pans made in the same way as the flower-pot are found to be a convenient substitute for baskets, as they are not so liable to decay as wood-baskets.