26 PLANNING THE HOME GARDEN 



the growth of the other plants. Oftentimes certain plants 

 will grow as companion plants throughout the life of both, 

 as, for example, pole beans and pumpkins grown with sweet 

 corn. These plants adapt themselves to each other's company 

 and will produce profitable crops in this way. A companion 

 crop, then, might be defined as a plant which associates with 

 another plant for a certain portion of its life. 



Rotation of plants is more or less common and differs from 

 succession and companion planting in that two years are 

 required for its operation while only one season is necessary 

 for the other two systems. When we rotate a crop we mean 

 that we follow one crop with another different one the 

 following season. 



Vegetables Grown for Their Roots. The root crops include 

 some of our most important vegetables. These plants are 

 grown for their underground parts. In most cases it is the 

 developed root of the plant, although in the case of the Irish 

 potato it is the enlarged stem. 



The conditions necessary for the growth of the root crops 

 are similar, and while there are special requirements for 

 certain ones a few general conditions are common to all. 

 In the first place, all root crops do the best when they are 

 grown on a light sandy soil. This is due to the fact that the 

 edible part, being a root, must enlarge sufficiently to produce 

 food. Since the soil offers resistance to the growth of an 

 enlarged root it is always advisable to select those soils 

 which offer the least resistance to the rapid expansion of the 

 underground part. 



A deep, well-pulverized seed-bed is also necessary for all 

 underground crops. This allows the parts to enlarge with 

 the least resistance. In such plants as the parsnip, carrot 

 and salsify, that develop long roots, it is especially desirable 

 that the seed-bed be deep because knotty, crooked roots will 

 develop if the root strikes a hard pan that hinders its down- 

 ward growth. Another detrimental factor that is often found 

 on such plants where growth is restricted by heavy soils is 

 the development of many small fibrous roots over the surface 

 of the large root. This makes the product unsightly, of 

 inferior quality and reduces its value. 



