50 orchids: how to grow them successfully. 



grow on the seedlings in a similar temperature to that in which 

 the old plants have been grov^Ti. 



DISEASES OF ORCHIDS. 



Orchids, like all other plants, are subject to disease, but this 

 appears most frequently where a wrong course of treatment has 

 been followed. Cattleyas and Laelias are sometimes attacked by a 

 fungoid growth which causes the pseudo bulbs and leaves to be 

 marked their whole length with black marks and spots, and if not 

 stopped in time it quickly destroys the plant by causing the pores 

 to rot and become putrid. When these marks are obseiwed the 

 darkened point should be cut through with a sharp knife up the 

 entire length of the mark, and a little dry slacked Hme rubbed into 

 the cut — this will sometimes X3revent the disease from spreading 

 any further. The disease, however, rarely occurs amongst healthy 

 plants, and it may generally be attributed to a badly ventilated 

 atmosphere, or to the compost about the roots being in a highly 

 decomposed state. The genus Phalsenopsis are subject to a 

 disease known as "Spot," which, if not cut out and powdered 

 with hme or charcoal dust, will quickly spread. This "Spot" 

 is caused by bad ventilation, and when the growth is too " sappy," 

 or fi'om an excess of moisture during the dull days of winter. 

 The foKage of Odontoglossum vexillarium is also subject to 

 spotting, but only when it is grown in too cold a temperature, 

 kept too wet, or when insufficient air is given during winter. 

 The same may be said of Vanda cserulea, which is a plant 

 that must be grown in a light, airy, and moderately warm 

 atmosphere during the winter, or the leaves will become badly 

 spotted. In fact all Orchids have some ailments, more or less 

 severe if theii- treatment is wrong, and the safest plan is to 

 well ascertain their requirements and see that these are obtained 

 as nearly as possible. 



WATERING AND RESTING ORCHIDS. 



This must be regulated by theii' season of growth. For 

 instance, a Dendrobium just starting into growth in early spring 

 will require only very little water, just enough to prevent the 

 compost from becoming dust dry, as the old pseudo bulbs at this 



