148 



GAEDENTN*G FOE THE SOUTH. 



heat in green-houses, are often entirely counteracted, and 

 plant growth brought to a stand, by watering with cold 

 water. It is not only the lowering the temperature of 

 the roots of plants, but the suddenness of the change 

 that is injurious and. often fatal. Water should always 

 be applied a few degrees warmer than the soil, that growth 

 may be promoted and not checked. 



As to the time of day at which water should be given, 

 unless applied quite freely, it does little good in the heat 

 of a summer's day, as the hot atmosphere drinks up the 

 moisture before the plant can imbibe it. The effect of 

 rain can be best secured by watering just at night, when 

 the falling dew will, in some measure, prevent evaporation 

 from the plants, and they get fully refreshed during the 

 night. But in the spring of the year, to water in the even- 

 ing in dry weather darkens the soil, and, therefore, increas- 

 es radiation. Evaporation is also greatly increased ; the tem- 

 perature sinks rapidly, the plants are chilled, if not frozen, 

 and make less growth than if not watered at all. So, also, 

 in autumn, for the same reason, at those times water only in 

 the morning, and the heat of the soil will not be materially 

 lowered, the sun's rays communicating fresh warmth. 



It should be the great object of the gardener to avoid 

 the necessity of watering, by shading the earth or the plants 

 themselves, by mulching, top-dressing, or sun shades. Seeds 

 will come up much more satisfactorily in the open ground 

 if shaded, than if one depends upon watering. If water- 

 ing is resorted to at all, it should be given copiously and 

 the supply kept up until the plants are established. After 

 watering, the ground should be stirred about the plants, if 

 up, as soon as it is sufficiently dry, and never allowed to 

 become hard. A mulching of leaf mould is desirable, to 

 keep the surface in a proper state, and if applied when the 

 surface is wet, it will prevent the necessity of repeated wa- 

 terings. — (De Candolle, Lindley, Mc'Intosh.) 



Summer Cultivation— If before seeds are planted, the 



