THE BULB BOOK 



The main object of using the syringe is to counteract the process 

 of evaporation that is going on unseen to the naked eye from the 

 leaf stomata. " Unseen " is perhaps scarcely accurate, for it becomes 

 obvious on a hot day (even when the soil around the root is quite 

 moist) that unless the syringe is used to moisten the air, the leaves 

 soon begin to droop. Why is this ? Simply because the cells are 

 being emptied by evaporation of the water that has been supplied 

 to them by the roots. It may therefore happen, and frequently 

 does happen, that the leaves of a plant will give off moisture much 

 more quickly than the roots can absorb it from the soil. In such 

 cases, therefore, it becomes not only necessary to syringe the foliage 

 freely, but also to lessen the amount of sunshine by shading the 

 glass with canvas, or smearing it with whitewash or other mixtures 

 used for the purpose. 



There are now many syringes on the market, but it is advisable 

 to have those that give a fine mist-like spray, and are provided with 

 suitable nozzles and bends. The finer the spray, the more perfect 

 is the wetting of the foliage ; and if insecticides or fungicides are 

 used under other conditions, the more economically and effectively 

 will they be distributed with a good syringe. 



A secondary advantage of syringing plants is that the foliage is 

 kept clean from dusty or sooty deposits. These if allowed to remain 

 too long, block up the breathing pores (stomata) to a great extent, 

 and thus interfere with the absorption of carbonic acid gas from the 

 atmosphere during the daytime, as well as with the exhalation of 

 oxygen from the tissues. Dust, dirt, or any other foreign deposit 

 on the leaves and stems of plants, not only render breathing difficult, 

 but as the supply of light is also diminished by their presence, the 

 work of assimilating the food from the air and the soil is greatly 

 impeded. The result sooner or later is a yellowish, sickly, dirty 

 appearance of the whole plant. 



Sponging. — This operation is often performed on the leaves and 

 stems of plants grown under glass, when they happen to be badly 

 affected by insect pests such as scale or mealy bug, or covered with 

 dirt that cannot be readily removed by syringing. It consists in 

 washing the leaf surfaces often with clean tepid water, but usually 

 with a solution of soft soap, quassia chip, or nicotine, or some of the 

 weU-advertised insecticides and fungicides. The leaves are placed 

 on the outstretched fingers and palm of one hand, and carefully- 

 washed with a sponge saturated in the solution. In this way pests 

 and dirt are removed, more light and fresh air are given to the 



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