240 JOTTINGS OF A GENTLEMAN GARDENER 



(10) Date when plants in different plots began to differ 



and in what respect, 

 (n) Particulars at least each week for each plot on 



the growth of the plants. 



(12) Date when the Experiment was ended. Particulars 

 of final effects, and of any sudden change of 

 weather conditions during the trials. 



At the end of the Experiment summarise the results and 

 compare those of the several plots. In the case of manure 

 for instance, it will then be possible to see its effect and 

 to judge whether it is good enough for future use. 



Subjects for experiments are extremely numerous, but 

 many of them are rather difficult to begin on. Small 

 experiments are the best to start with : trials of some of 

 the simple single-chemical manures mentioned in Chapter 

 XXVI with different plants prove extremely interesting, 

 but in every case there should be a " control " example, 

 i.e. plants not dressed with the manure at all, or dressed 

 with a manure the effects of which are known. As readers 

 gain experience, learnt by careful painstaking experiment, 

 they may begin compounding for themselves " complete " 

 fertilisers, and try their effect on the plants in their flower 

 borders. 



Experiments with soil fumigants have already been 

 mentioned. Those used may either be home-made or 

 proprietary articles. Very interesting experiments can be 

 made also with proprietary fertilisers. 



Experiments like those which are concerned with humus 

 and the soil are not so simple ; but there is plenty of work 

 for anyone interested in this subject. There are many 

 problems to be solved, but most important of all is the one 

 outlined in Chapter XXVII how to turn vegetable 

 manure into a full, perfect, and complete substitute for 

 stable or other animal manure. 



Many more subjects of investigation might be mentioned, 

 but my main object has been to indicate how absolutely 

 fascinating even simple experiments are, and to induce 

 some of my readers to try them themselves. 



