AucustT, 1906.] THE ORCHID REVIEW. 229 
CALENDAR OF OPERATIONS FOR AUGUST. 
By J. M. Brack, Streatham. 
DeENDRoBIUMS.—By the middle of the month a good many Dendrobiums 
will be showing their last leaf, an indication that their growing season is 
drawing to a close. Last year, when we had at Chessington a house 
entirely devoted to these plants, no more shading was used after the middle 
of August, and no scalding took place, nor yet did the plants lose their 
leaves. Those plants which were still in strong growth made perhaps some 
little haste to finish up, and the pseudobulbs were probably a little shorter 
than they would have been had shading and close growing conditions been 
continued longer, but the same number of nodes were produced, the inter- 
nodes being shorter. There is little doubt that it is better to make full use 
of the late August and September sun to thoroughly ripen the new pseudo- 
bulbs, rather than resort to cold vinery treatment and starvation during the 
winter. The sunning need not be suddenly applied, but gradually, and the 
plants being now in full leaf and thoroughly rooted, and receiving full sun 
and more air, a greater quantity of water at the root will have to be given 
than at any time during the summer. The top ventilators must still be 
closed as soon as safe during the afternoon, so that growing conditions are 
not really discontinued. A great increase in leaf transpiration will follow 
this bright and airy treatment, which willstimulate root action, and the pots 
will rapidly become matted with fine healthy roots. Any loss in the length 
of the pseudobulbs will be fully compensated for in their increased girth, 
and the yellow hard pseudobulbs may be relied upon to yield a harvest of 
blooms on pedicles stout enough to support them. A soft grown Dendro- 
bium may have its flowers hanging limply, head downwards, round the bulb, 
especially if it has outgrown its strergth, and become rickety through super- 
abundance of nitrogenous food. The weak point in this wholesale treatment 
of a house of plants would seem to be that plants that are only half grown 
are having the same treatment as those on the point of finishing, but this is 
really not a question of so much importance as it would at first sight appear, 
as no plant is being starved either for water at the root:or for heat. The 
closing of the top ventilators early in the afternoon is really very necessary 
for some time yet. 
This autumn treatment will suit excellently well such Dendrobes of 
different character as are represented by D. nobile, the nobile and aureum 
hybrids, D. Phalzenopsis, D. formosum (which will be making up its buds), 
D. Brymerianum, D. Dalhousieanum, D. thyrsifloruam, and other hot 
growing kinds. D. aureum finishes early, is wholly deciduous, and may be 
taken into a cool house, and it will require but little water once the bulbs 
are thoroughly ripe. D. Wardianum should also be kept somewhat cvoler 
