MULCHING, SHADING, AND WATERING. 147 



plied to the foliage. Trained against the walls, evapora- 

 tion goes on very rapidly from the heat reflected upon 

 them, and but very little rain falls upon the foliage. 

 They also become covered with dust and their pores chok- 

 ed therewith. When the sun shines warm and brightly, 

 plants should be watered only about the roots, for if ap- 

 plied to the foliage, the drops, remaining thereon, act as 

 so many burning glasses, and scorch the leaves, covering 

 them with brown spots wherever the water rests. But 

 in the spring, when the earth is moist, if the air is dry, and 

 indeed at all times when the atmosphere is dry, and par- 

 ticularly when plants become covered with dust, they will 

 be greatly refreshed by syringing or sprinkling the foliage 

 in the evening or morning, if their leaves are not suscep- 

 tible of change by humidity. 



Plants in pots should be watered frequently and little 

 at a time. If the ball has become dry, do not deluge it 

 at once, as it will flow directly through the pot or out at 

 the sides, carrying with it the richness of the soil, while 

 the ball still remains dry. Give it a little water, and when 

 that soaks up, give, a few minutes after, a little more, until 

 the entire ball is in a suitable state of humidity. The 

 drainage must be good, or if much water is given to plants 

 in pots, the soil will become heavy, water-logged, and im- 

 pervious to the atmosphere. 



The best water to use is rain water, caught in open cis- 

 terns, as it is well aerated and abounds in ammonia and fer- 

 tilizing gases. If spring or well water must be used, add 

 a very little guano, say a pound or two to twenty gallons 

 of water, giving the smaller quantity to delicate plants, 

 and the larger to gross feeders, and before using let it 

 stand a few hours. Manure from the hen roost in double 

 quantity may be substituted for guano. For sprinkling 

 the foliage, pure water is better. 



The temperature of water, too, must be regarded. The 

 good effects of bottom heat in hot-beds, or of artificial 



