76 VEGETABLE GARDENING. 



still quite cold and frosty. It is then that the beginner often 

 makes the mistake of leaving the sashes of his hotbeds open 

 late in the afternoon, and the beds cool off more than is de- 

 sirable. At this season of the year but little ventilation is 

 necessary and frames and greenhouses should be shut up 

 quite early in the afternoon, and the covering put on to retain 

 the heat as soon as the sun is low. In the warm weather of 

 later spring, the sash of the hotbeds and frames may be re- 

 moved in the day and kept on only at night. No exact rules 

 can be laid down for ventilating, but it is quite a simple 

 matter to learn, if one is observing and uses constant vigi- 

 lance. Many persons just beginning to use greenhouses and 

 hotbeds fail to get best results from them, because they neglect 

 the matter of ventilation. On cloudy mornings it may not be 

 needed, but if the sun comes through the clouds it may warm 

 the house, or the beds in a very short time, so that when they 

 are examined the whole crop has been injured by the heat. 

 This is a most common cause of failure by amateurs in charge 

 of greenhouses and hotbeds. 



In nature, the night temperature in which plants grow 

 averages from fifteen to twenty degrees below that of the day, 

 and it has been found in practice that when this condition is 

 reversed the plants do not do well. This, of course, can be 

 easily avoided by a little forethought. It is a bad plan, gener- 

 ally speaking, to ventilate much in cold weather when the 

 leaves are wet. On this account it is best to water early in 

 the day, so that the leaves may dry off before much ventilation 

 is required. 



Watering. Plants that are growing slowly do not need 

 much water, while those that are growing vigorously need a 

 great deal of it. Growing plants need water whenever they 

 are dry. In bright warm weather a rapid growing crop in 

 hotbed or cold frame will need watering every day, while in 

 cloudy, moist weather perhaps no water will be needed for a 

 week. In fact, watering in cloudy weather seems to encourage 

 disease. When applying water see that the soil is wet as far 

 down as the roots extend. It is only the beginner who just 

 wets the surface soil and thinks the plants sufficiently watered. 

 If plants are wilting for want of water in the soil, give it to 

 them no matter what the time of day, but it is always a great 



