176 ORCHIDS : HOW TO GROW THEM SUCCESSFULLY. 



the old flower stem and sheath immediately after blooming and slightly powder 

 the wound with charcoal. This together with the air soon dries up the wound, 

 and decay does not again appear unless the culture of the plant is greatly at 

 fault. It is the autumn blooming species of the Cattleya which more strictly 

 require this attention. 



6. What is the probable cause of Calanthe vestita oculata failing to throw 

 flower spikes (after full sized bulbs have been formed), whilst C. Veitchii is 

 blooming freely ? The Vestita oculata were grown singly in 60-sized pots ; the 

 Veitchii in large pots with 3 or 4 plants in each in other respects the treatment 

 of both species was apparently the same. 



REPLY. I cannot understand the cause of this, and it is difficult to assign 

 a reason why your Calanthe vestita oculata failed to flower after making full 

 sized bulbs as it is generally so very free blooming. The flower spikes may have 

 been injured and destroyed unobserved when very young ; or that the plant 

 may have received a violent check which stopped all further growth. A large 

 60-sized pot is very small for a full-sized bulb of Calanthe vestita, and I advise 

 the use of a 48 -size. 



W. T. O., SCOTLAND, writes : I think if you gave a little more 

 information as to ventilation, especially as regards night ventilation, it would 

 be useful. Also, I have this year had great trouble with the Cattleya fly. I 

 never had it before and imagine it was introduced with some imported plants 

 of C. labiata vera. A little more information on that beast would be welcomed. 

 Odontoglossum grande and Miltonia vexillaria I cannot manage at all. I have 

 only one house to spare for Orchids, an Intermediate house, but these two 

 Orchids will not thrive although I manage Cattleyas all right. 



REPLY. Your first question will, I think, be answered under the heading 

 of "Ventilation" by additional information given. The Cattleya fly is indeed 

 a terrible pest. Should your plants be newly imported, look well into them and 

 search for crippled growths or imperfect pseudobulbs, and examine them 

 closely to see if the fly has been the cause of the mischief. If so, a hole will be 

 somewhere near the base of the crippled growth from which the fly escaped on 

 reaching maturity. If no hole can be seen, and yet still a suspicion that the 

 fly has been there, then give the suspected growth a wrench and it will 

 invariably break owing to its being hollowed out by the grub. It does not 

 follow that the live larvae is sure still to be in the plant, but it is probably so, and 

 should be closely watched for. Too much caution cannot be exercised in buying 

 established plants, for it has been in connection with the purchase of such 

 plants that I once had a very narrow escape from a serious attack of the 

 Cattleya fly, and I am afraid that plants are sometimes sent to sales when found 

 to be affected by this insect, without any thought on the part of the sender as 

 to the great risk to the buyer. I am not quite sure whether this pest is not 

 sometimes bred upon ill cared for plants, not spontaneously. 



Your Intermediate house should grow Odontoglossum grande and 

 Miltonia vexillaria quite well, but, perhaps, your plants have got into bad 

 condition, if so, do not let them bloom and repot into small pots. I have heard 

 of a few lumps of ammonia placed under the stages being a great stimulant to 

 restoring unhealthy plants to greater vigour, but am not a great believer in it. 



