24 VEGETABLE GARDEN IN a 



ROTATION OF CROPS 



By rotation is meant the special succession of crops 

 growing upon the land for a series of years. This is very 

 desirable even on land in the highest state of cultivation, 

 but it is very difficult to lay down exact rules to be 

 followed. 



Reasons for Rotating Crops. We rotate crops for at least 

 six reasons: (1) To avoid insect enemies, as in the 

 case of onions and turnips, which are often liable to serious 

 insect injuries when grown more than one year on the same 

 land. Turnips are especially liable to injury from insects 

 when grown in the same place successively. 



(2) To avoid injuries from fungous diseases, i. e., in 

 case of potato and beet scab, onion and melon rust, corn 

 smut, etc. 



(3) To increase the amount of humus in the soil, and for 

 this purpose we may seed down the land to grass or clover. 



(4) To deepen the soil and add nitrogen to it as well as 

 humus, as when clover is grown on the land. 



(5) To get rid of weed seeds in the soil. 



(6) To use the plant food in the land to best advantage, 

 since crops vary very much in the amount of the different 

 elements which enter into their composition. Leguminous 

 crops like clover, peas, beans, etc., improve the land on 

 which they grow, while most other crops exhaust the soil. 

 Some plants excel others in their power to search for plant 

 food, or to take plant food from the soil. Some plants 

 feed near the surface largely, while others take their food 

 mostly from a lower level. Root crops should not 

 follow root crops, nor should vines follow vines for many 

 years in succession on the same land. 



