142 



THE GREEN-HOUSE. 



manures, heat at an usual season, &c. in proportion 

 to the effects they produce, leave a corresponding 

 weakness when withdrawn. An extraordinary pro- 

 duce of blossoms, or fruits, in any one season, is com- 

 monly followed by a less than ordinary display in the 

 season following. 



The two greatest stimulants to growth are water 

 and heat ; the one should never be applied to any 

 great extent without the other, and both should be 

 used rather to second the efforts of nature, than to 

 force her into activity. Thus, when plants are grow- 

 ing vigorously they should be watered freely; when 

 slowly, sparingly ; when dormant very seldom ; and 

 in the case of bulbs and tubers in a dormant state, 

 scarcely at all till shortly before their season of re- 

 vegetation. 



As water and heat are the greatest stimulants to 

 growth, so light is the greatest stimulant to perfect 

 that growth, and render it mature. Plants will grow 

 for a time with water, heat, and air only, but not 

 long ; and their productions will never be of a green 

 colour ; nor will their blossoms or fruits ever arrive 

 at the slightest degree of perfection. 



The art of man can supply to plants everything 

 but light ; therefore, in placing plants in artificial cir- 

 cumstances, light is the first object requiring atten- 

 tion. Plants, to enjoy the full benefit of light, must 

 enjoy it directly from the sun ; light which has its 

 rays much deranged "by refraction or decomposition, 

 as by a prism for example, will not produce the same 



