The Greenhouse and Frame 229 
grafting. The plants can generally be bought very 
cheaply from the nurseryman, well set with buds or in 
flower. 
We have now to turn our attention to keeping our 
plants in perfect health when obtained. To do this we 
must understand a few special points regarding them. 
1. They do not like to be disturbed too often when 
once they are established, therefore potting should be 
done only once in two or three years. Porous sandy 
peat (for preference) should be used, or 3 parts of good 
fibrous loam, 1 part leaf mould, and from to 1 part 
of sand. The drainage of the pots must be good. 2. 
They must have plenty of water during the flowering 
and growing season, with less during the resting period. 
3. They must have plenty of light and air always to 
ripen the wood and thus ensure the production of plenty 
of flowers. 
The best time for potting is shortly after the flower- 
ing season, when growth is commencing. The roots will 
then enter the fresh soil, taking up the moisture and thus 
preventing injury being done by moisture being retained 
in it. Azaleas thrive best when potted firmly. 
Thrips and Red Spider are the great enemies of these 
plants, but if the latter are carefully watered, and the 
greenhouse well ventilated, there is less fear of attack 
from these pests. For particulars of these pests see 
chapter XV. 
Dracaenas. — These plants, though not so showy as 
the plants previously dealt with, are yet the most useful of 
our greenhouse plants; they may be mixed with the other 
flowering plants, when their graceful foliage gives a free- 
