MONTHLY CALENDAR. 287 



7S5. Now is the time to destroy scale, so troublesome on these beautiful and 

 graceful plants. — D. T. F. 



§ 7. — Fruit-Culture under Glass. 



786. ]\rarch is a peculiarly trying month for forcing. The extreme change- 

 ableness of the weather, varying almost every hour, from the fiercest sunshine 

 to the bitterest cold, and both these forces to contend against at once, render 

 the utmost attention necessary. This is the more essential, as at this season 

 the young foliage and fruit are so easily injured. Perfect ventilation may be 

 said to constitute the main feature of successful cultivation throughout the 

 month. The powerfiU rays of the sun compel us to give air,— the keen wither- 

 ing wind says. Do it at your peril. Both must be obeyed ; but a skilful balance, 

 resulting in a genial atmosphere, must be struck between these contending 

 forces. The moment, too, that one ceases to act, the other must be checked. 

 Does a genial mild March day for once occur, then you have only to guard 

 against the sun's rays. Is there no sunshine, then you have the cold air only 

 to combat. This principle must be applied to hours and minutes, as well as 

 clays. The moment a black cloud intervenes between your glass and the sun, 

 the au- must be excluded ; no sooner does the sun emerge from the other side, 

 than air must be admitted. Hence the extraordinary attention required, and 

 labour involved in ventilating houses during the month. 



787. March winds are not only cold, but dry. In fact, in mercy to the 

 comfort of men and the well-being of plants, it has been ordained that the 

 colder the air the drier it is. This fact renders it of the utmost importance that 

 every space in forcing-houses should be kept damp during bright weather in the 

 spring month. The inside air is not only to be warm, but it must be kept moist. 

 Every particle of outside air admitted, becomes charged with it, exhausting 

 the moistvu-e so necessary to the existence of the plants, extracting the water 

 out of the leaves, and leaving them thin, dry, and parched. Lay it down then 

 as a principle of universal appHcation, that the less of the cold air admitted this 

 month (consistent with the maintenance of a proj^er temperature, and a change 

 of atmosphere in the house), the better, and that the more you are compelled 

 to admit, the more water must be used to supply the demand that cold air 

 makes for water. This principle reduced to practice will secure in every plant- 

 structure at all times that greatest of all cultural desiderata, a genial, kindly- 

 growing atmosphere. 



788. Vineries. — The above remarks are peculiarly applicable to grape vines in 

 the early stages of their growth. When fully expanded, the leaves will bear the 

 strongest sun, and exposure to a cold air in the autumn, without inconvenience ; 

 but when young they are very easily injured. The earliest grapes may no'^ b 

 stoning. Don't attempt to hurry them during this process ; for, in the tir^t 

 place, you will not succeed, and, in the second, you will certainly weaken the 

 vines. This process occurs when the grapes are about three pails gi-own, and 

 often causes vexation and disappointment to young beginners. The grapea 



