196 THE BOOK OF THE ROSE chap. 



the enemy are sure to have escaped : a close ex- 

 amination the next day is necessary, and often a 

 second application may be desirable. 



When the blooms are just ready to open we may 

 take a hint from Nature, and, remembering that 

 Boses in the open, especially H.P.s, are far better 

 when a dull cooler day follows after some hot 

 weather, endeavour to shade the plants from the 

 full sun, and keep them, if possible, a little cooler. 

 If a light blind be used, or the glass roof be syringed 

 on the outside with a mixture of whiting and milk, 

 or some similar clouding material, the flowers will 

 be brighter, more lasting, and altogether of better 

 quality. 



Ventilation is a most important matter in all forms 

 of Rose cultivation under glass : the foliage is very 

 tender, and a cold draught is almost sure to bring on 

 mildew. It is far better to give no air at all than to 

 open the ventilators to an icy wind. Still, Eoses 

 must have air, and there will be few days when it 

 cannot be admitted on the lee side for an hour or 

 even less. Where the plants are grown in beds in 

 a cool house, air should be given as often as possible, 

 and in increased quantities as the season progresses : 

 the final removing of the roof or top lights, after the 

 plants have bloomed once, should be arrived at by 

 gradual and easy stages, so that as little check as 

 possible may be felt when all covering is taken away. 



As an early second crop of flowers may be expected, 

 and a third from some of the freest sorts, especially 

 of Teas, it is necessary that the feeding and culti- 

 vation of the soil should not be forgotten, or the 

 plants neglected because the outdoor Eoses claim so 

 much attention. Some of the weaker shoots may be 



