LECTURE ON SPRING FLOWERS. 343 



conservatories and halls at that season that we cannot 

 possibly overlook them. 



The art of " forcing " consists in accelerating the period 

 of perfection of fruits and flowers. The practice is simple, 

 but nevertheless requires an amount of knowledge, care, and 

 watchfulness which thoroughly test the capabilities of the 

 cultivator. By forcing, the fruits which ripen naturally in 

 autumn are brought to perfection in spring and summer ; 

 the flowers of summer are induced to bloom in winter and 

 in spring. Here, as with spring flowers, the glass structures 

 should be as light as possible. A low night temperature 

 should also<be insisted on. Plants unduly excited or over- 

 worked by a high temperature during the day, require the 

 restorative of periodical rest, and this is best provided for 

 by a low night temperature. A difference of 15 or 20 

 between the maximum of day and night temperature is 

 seldom too much. The syringe must be used freely every 

 morning and evening when forcing, in order to prevent the 

 exhaustive effects of hot dry air ; and the quantity of water 

 sprinkled over the plants and house must be greater during 

 sunny than cloudy days, and in proportion to the increase 

 of temperature. It is well to lower the temperature of the 

 forcing house when the plants have arrived at that stage of 

 development at which the flower buds begin to colour. 

 The period of expansion is of course retarded by this 

 practice, but then the flowers are much better developed, 

 and the colours are stronger. 



A great deal might be said on the preparation of plants 

 for forcing. Those of us who are accustomed to deal with 

 plants in this way know well that we may change the 

 flowering season of almost any plant. For instance, the 

 Rose, which naturally blooms in summer and rests in 

 winter, may be made to rest in summer and bloom in 

 winter. By a long-continued course of systematic treat- 

 ment the seasons may be completely reversed. Cold and 

 drought are the agencies by which we effect this ; and in 

 the absence of the one we may accomplish the end in view 



