GREENHOUSE MANAGEMENT 425 



treatment, and each of which is likely to be attacked by disease 

 and insect pests that are its own peculiar enemies. A self- 

 registering thermometer which shows maximum and mini- 

 mum temperatures will be found an indispensable adjunct to the 

 greenhouse. 



The art of stoking is not one that can be acquired immediately 

 or without effort, but if an efficient heating apparatus be in- 

 stalled, and if it be in perfect order, a little practice will soon 

 disclose the difficulties that need to be surmounted. The vast 

 majority of the owners of small greenhouses possess only one 

 heated glass structure and they do not therefore attempt the 

 higher flights of stove plant cultivation. They are content if 

 during winter they can maintain a temperature which varies 

 between 45 and 70, and they learn very speedily, after a 

 brief experience, that the secret of success lies in maintaining 

 the atmosphere of the greenhouse in a buoyant condition, brought 

 about by keeping the air constantly in circulation. 



To produce this satisfactory and ideal state of things it is 

 necessary to be a good stoker. The enthusiast will make a close 

 and constant study of the weather, so that he may check im- 

 mediately any tendency towards a too rapid rise in temperature, 

 or may stimulate the heat if outside there be any indications of 

 frost. He will carefully examine his heating apparatus so that he 

 may understand the principles on which it works ; will ascertain 

 whether there are any signs of leakage in the pipes, and will either 

 put them right himself or call in the aid of a hot-water engineer 

 or horticultural builder. This precaution is necessary since if there 

 be any serious leakage, and the pipes become empty, there is great 

 probability that the section nearest the stove will become red-hot, 

 and if that unfortunately occurs the adjacent wood is certain to 

 be scorched even if it does not actually catch alight and involve 

 the whole structure in destruction. 



The efficient stoker will likewise pay close attention to the 

 provision of suitable fuel. He must remember that his aim will 

 be to ensure the fire burning steadily throughout the long and cold 

 nights of winter, and he will find that the best fuel for this pur- 



