FLORICULTURE 513 



Owing to the fact that we have no definite rules to follow in 

 this matter, it would be well for everyone growing plants on a large 

 scale to have constantly under way experiments to obtain light on the 

 subject. Such experiments may be made on a small scale, will cost 

 but little, and would doubtless be the means of bringing many inter- 

 esting facts to light. Some soils that do not give the best results for 

 certain crops might be greatly improved by the addition of clay, 

 sand, or silt ; in fact, there are any number of combinations in this 

 direction that might be used to advantage. 



Water, Heat, and Light. The importance of water in the 

 growth of plants under glass has already been briefly referred to in 

 discussing the question of soils. It is hardly necessary to say that 

 the proper use of this element is the keynote to success; in fact, it 

 has been truly said that he who does not know how to water plants 

 does not know how to grow them. No absolute rules can be laid 

 down for the use of this all-important material, as knowledge on such 

 matters can be gained only by experience and the closest observation. 



As pointed out in discussing the soil, the amount of air it con- 

 tains has an important bearing on the health and vigor of the plant. 

 Water plays a very important part in this matter, for the more water 

 there is in the soil the less space will there be for air. By the im- 

 proper use of water, therefore, air is excluded from the soil and vari- 

 ous complications are brought about, all of which directly affect the 

 health, vigor, and productiveness of the plants. One of the results 

 of the improper use of water in a soil naturally heavy is the forma- 

 tion in the roots of plants of alcohol and other substances destructive 

 to growth. The roots in such cases are slowly suffocated, and the 

 gradual decline and death of the plant is the result. 



The improper use of water may affect plants in another way. 

 The soil may be made a little too wet, and the air in the houses may 

 also be oversupplied with moisture. These conditions are most likely 

 to occur in winter. As a result of this certain changes are brought 

 about in the tissues which make them more subject to the attacks of 

 parasites, especially fungi, and also render them liable to other in- 

 juries, such as burning, scald, spot, etc. 



Although not generally recognized, the method of applying 

 water may have a decided effect on the growth of the plant by chang- 

 ing the structure of the soil, i. e., the arrangement of the soil grains 

 and their relation to each other. It will be seen that the continuous 

 and more or less forcible application of water to the surface of a soil 

 on a greenhouse bench will have effects similar to dashing rains out 

 of doors, that is, it will compact and puddle the soil and wash the 

 smaller materials to the bottom, thereby changing its capacity for air, 

 heat, etc., and thus directly influencing the development of the plant. 



The soil should be kept open at all times to the free access of air. 

 This may be done by keeping the surface stirred, by careful attention 

 to watering, and, as is frequently done, by using a light mulch of 

 manure or some suitable material to break the force of the falling 

 water 



