94 FRUIT CULTURE UNDER GLASS. 



should not be withheld when the vines are in flower. 

 Atmospheric moisture, however, must not be carried 

 to excess, especially in the mornings. An over- 

 moist atmosphere when the house cannot be regularly 

 and freely ventilated, to a certainty produces those 

 excrescences so often met with on the under sides 

 of vine-leaves, in dull wet seasons especially. It is 

 desirable to follow nature as far as possible, and the 

 foliage of vines and all plants should be allowed 

 to become perfectly dry, and surrounded with a com- 

 paratively dry air for a time, once in the twenty- 

 four hours. It gives a texture and strength to the 

 foliage which cannot be attained under the influence 

 of too much moisture. When colouring is first noticed, 

 avoid withdrawing the moisture suddenly, but let it 

 be done gradually till it ceases altogether, when the 

 grapes are nearly fully coloured. A dry air is favour- 

 able to the proper ripening of grapes which have to 

 hang for months after being ripe, and fire-heat should 

 be applied at intervals in fine days, when the ven- 

 tilators can be opened to carry off the moisture. On 

 damp days it is best to keep the house shut up. 



It is not very easy to give definite directions how 

 often borders should be watered. If the borders are 

 well drained, and the soil open, vines when in full 

 growth and bearing require a great amount of water. 

 Before forcing commences, the border should have a 

 good soaking, and it should never afterwards be al- 

 lowed to get very dry. Whenever it shows signs of 

 dryness or cracking in the least, give a good watering, 

 always with water at 8 0°. I do not approve of allow- 

 ing inside borders to get mealy dry, even after the 

 grapes are ripe, or when they have all been cut. Even 

 then the constitution of the vine requires that the soil 



