THE GREEN-HOUSE. 



145 



charged with moisture, hence the daily attention re- 

 quired to admit fresh air and promote its circulation. 



As the presence of air is essential to the growth 

 of plants, and of fresh air to their healthy state, so 

 the action of wind is essential to their strength, 

 Strength of stem is not necessary to all plants, for 

 example, to creepers and climbers, Avhich, whatever 

 advantage they derive from air, benefit little or no- 

 thing from wind ; nor do they require to possess the 

 strength of stem which wind gives, because nature 

 has furnished them with the means of attaching 

 themselves to other plants with strong stems. Wind 

 produces in green-house plants what is called bushy- 

 ness, or a close compact branchy form, which is 

 always the best for a shrub in a pot, as a single stem 

 with a head is the best for a small tree, as in the 

 case of the orange. A salutary degree of wind is 

 admitted to the green-house by opening the doors, 

 and as much of the glazed covering and sides as 

 possible, when it is gently windy in the open air ; and 

 the full effect of wind is enjoyed when the plants are 

 set out in the open garden during the summer months. 

 One suggestion of importance we offer as connected 

 with the latter practice : it is, that when benefit is 

 expected from the wind, the tall plants should not be 

 tied to cross rods or lines by their tops, as is com- 

 monly the practice, but near the lower ends of their 

 stems. By this means the wind is enabled to bring 

 the upper part of the stem, that is, all that is above 

 the tie, into motion, — a thing essential to their bene- 



L 



