1911.1 PUBLIC DOCUMENT — No. 31. 145 



SWEET PEA TROUBLES. 



BY G. E. STONE. 



One of the most unsatinftietory types of troubles with which 

 the pathologist has to deal is that having no specific organism 

 as its primary cause. It is especially difficult to diagnose such 

 diseases where the conditions of growing the plants are almost 

 entirely unknown, and this is the case with most of the miser- 

 able, sickly looking sweet pea plants sent into the laboratory 

 for diagnosis. There may be well-defined troubles associated 

 with sweet peas, but from 1)0 to 100 i)er cent, of them may bi; 

 ])re\ented if the grower has even an elementary knowledge of 

 the conditions required by this plant. 



When sweet peas are planted in ])oor soil, without care or 

 j)reparation, unfavoral)le results may be looked for. That such 

 is too often the case is evident from an examination of the ma- 

 terial which is sent in for examination. To obtain a good cro]) 

 <tf sweet peas unusual care should be given to j)reparation. A 

 light soil is better than a heavy, compact soil. It is impossible 

 to grow this crop without a good depth of garden loam, and, if 

 this is not availalile, it must be secured by deep trenching and 

 heavy manuring. ]\Iost skillful gardeners maintain that the best 

 results are obtained by having a soil which the sweet pea roots 

 can penetrate deeply, and in which they can develop luxuriantly. 



A trench IY2 to 2 feet deep and the same width, filled with 

 maun re and loam, is usually sufficient. If a good depth of root 

 develojnuent is desired, it is best to sow the seeds in trenches 

 ■J to () inches below the surface, and as the plants mature the 

 soil can be gradually hoed around the stems. The many speci- 

 mens which we receive from growers testify to the poor condi- 

 tions in which the plants have been grown, there being little root 

 or stem development, and often tubercles on the roots are lack- 

 ing. Proper conditions count very much in growing sweet peas, 

 and w^hen these are given, many so-called " diseases " peculiar 

 to this plant disappear. 



