IRISH POTATOES 245 



barrel. The practice is not a bad one, as the potatoes are really better than 

 the real Bermudas. This second crop is usually planted where some early 

 crop was heavily fertilized and no extra fertilization is given it, as the pota- 

 toes are used mainly for seed and a very large size is not sought. 



In the mountain regions of the South the methods for growing late pota- 

 toes as practiced northward are the rule, and much of the supply of table pota- 

 toes for the Southern cities in winter comes from the mountains of North 

 Carolina. 



POTATOES IN THE HOME GARDEN. 



Many people in towns and villages, as well as some on the farm, like to 

 have a small patch of early potatoes for the table planted in the garden. Old 

 gardens are very poor places for potatoes unless they are carefully 

 treated. It is quite commonly heard after experiments in potato culture in 

 the home garden, "My garden is too rich for potatoes ; they all run to tops ;" 

 and the fact that they have gigantic tops and quite small tubers is very ap- 

 parent. Now the soil produced these great tops, and the great tops failed to 

 perform their duty for it is the top that makes the potato and here were 

 surely tops enough to have made a large crop, while the fact is the crop is 

 miserably small. Why is it thus? We have shown that the carbonaceous 

 matter in plants comes from the air through the power which the green matter 

 of the leaves has to decompose carbon di-oxide in the air take the carbon and 

 leave the oxygen. After taking the carbon, the plant in the leaf makes the 

 carbohydrates out of the carbon, oxygen and hydrogen taken from air and 

 soil. The first carbohydrate is probably some form of sugar for the im- 

 mediate sustenance of the living matter of the plant, and when this want is 

 supplied the plant forms starch as a storage form of food to keep for future 

 use. But it is found that the plant will not make (or cannot make) the 

 change from sugar to starch except in the presence of an abundant supply of 

 potash, in proportion to the nitrogen and phosphoric acid present. The effect 

 of nitrogen is to form a heavy growth of all parts of the plant, but especially 

 of the foliage. This heavy foliage ought to assimilate more carbon and store 

 more starch than a weaker growth, and it will do it if there is a proper pro- 

 portion of the mineral elements present. The old garden soil has grown 

 big tops and small potatoes, not because it is too rich, but because it is too 

 poor in phosphoric acid and potash. The soil has for years been manured 

 with stable manure until there is an excess of nitrogen over the other ele- 

 ments and the great growth is there, but it is a poorly balanced growth, and 

 the foliage cannot perform its part in the construction of starch, although 

 there is a great activity in all the vital functions of the plant and a very rapid 



