202 MANUAL OF AMERICAN GRAPE-GROWING 



being thinned too severely. Grapes intended for long keeping 

 require more thinning than those to be used at once after pick- 

 ing, since, in keeping, the berries mold or damp-off in the 

 center of the bunch if it is too compact. 



The vines in the grapery must be watered with considerable 

 care. The amount of water to be used depends on the composi- 

 tion of the borders and the season of growth. If the border 

 is loose and well-drained, the supply of water must be large; 

 if close and retentive, but a small amount of moisture is re- 

 quired. Watering must not be done during the period of 

 blossoming, since dry air is necessary for proper pollination. 

 When the grapes begin to show color, the vines are heavily 

 watered, after which little if any water is applied. Some gar- 

 deners mulch the vines with hay to retain the moisture in the 

 house and keep the atmosphere dry. 



Ventilating the grapery is another important detail of the 

 season's work. Proper ventilation is difficult to secure in the 

 early spring months when the dryness of the sun on the one 

 hand, and cold air on the other, make it difficult to avoid 

 draughts and regulate the temperature. Another troublesome 

 time is when the grapes begin to color, as it is then necessary 

 for the grapery to have air at night; but when too much air 

 enters, there is danger from mildew. Towards the end of the 

 season, all parts of the plant become harder in texture and the 

 grapery may then be more generously aired. After the fruit 

 is cut, the houses are ventilated in full so that the wood may 

 ripen properly. 



PESTS 



Several pests vex the gardener in growing grapes indoors. 

 Of these, mealy-bug, red-spider, thrips and mildew are most 

 troublesome. In a well-conducted grapery, there is never an 

 intermission in the warfare against these pests. 



Mealy-bug is usually a sign of sloth on the part of the gar- 



