CULTURE OF THE PINE-APPLE. 427 



the vapour for the leaves of the plants. This, with the rich odours arising 

 from fermenting materials, has always been valued by pine-growers as 

 imparting that hue and substance to the leaves which is the sure index 

 of robust health. Some even recommend syringing the plants with 

 manure-water overhead. As roots form in the axils of the leaves, 

 there is no doubt that pines may be fed in this manner. It is, how- 

 ever, better to diffuse such chemical fertilizers through the air than 

 apply them directly, in a grosser manner, through the syringe. To a 

 great extent, the same rule will hold good as to sprinkling the leaves of 

 plants with water. Some growers sprinkle incessantly, and others but 

 little. All, however, agree on the importance of a moist atmosphere, 

 unless in the depth of winter and at the flowering and finishing stages. 

 The fruit sets most freely in a tolerably dry atmosphere, and it ought 

 to be flavoured off in the driest air consistent with health. At all 

 other times an atmosphere bordering on saturation may be maintained. 

 Some provide this moisture by its direct application to the leaves and 

 stems, others by filling the houses with steam, while more generate the 

 aqueous vapour by sprinkling the walls, pipes, floor, and every 

 available surface with water. By such means the whole air is slowly, 

 but surely, charged with vapour. The time for this general watering 

 of the air or surface of pine-houses is from four to five o'clock in the 

 afternoon. The houses are then shut up, and the increased heat 

 raises the water, and gives the plants a stimulating vapour bath. 

 During the swelling of the fruit, water is generally applied directly 

 to its surface for several of the summer months. And as, im- 

 mediately after potting, or during the bright days and frosty nights 

 of March, there is a double drain upon the water of the pine-pits or 

 houses, that of the sun by day, and of the cold glass at night, the 

 sprinkling of paths, walls, &c. should be repeated many times during 

 the day. Double glazing or the slight covering at night of such houses or 

 all houses at high temperature, would not only preserve their heat, but 

 husband their moisture. Such expedients should therefore be adopted 

 for pine-houses. 



Manures. None to be given to the soil, with the exception of bones, 

 roots of grasses, and charcoal, if indeed the latter should be so called. 

 In a liquid state, any stimulating manure, applied clear and weak, such 

 as sewage, animal excrements, and especially guano, and soot- water, 

 may be used. Carbonate of ammonia, at the rate of one ounce to 

 four gallons of water, has likewise been recommended. 



Ventilation. More or less air should be given every day, if the 

 weather will permit of it. In fact, the air of the house should move 

 night and day if possible, and a gradual exchange between the ex- 

 hausted air within and the free strong air without be constantly going 

 on, so gradually as to renew and move the air without creating 

 draughts. This circulation of air may be carried on without greatly 

 affecting the temperature. It is best effected by admitting a modicum 

 of outside air in front, beneath the hot-water pipes. Before it reaches 

 the level of the plants, it will be warmed and saturated ; still it is fresh 

 new air, and will supply the place of that which is exhausted. 



