THE KINDS OF PLANTS 



111 



are in this class. They are called perennial plants. Some 

 few plants live but two years, and are called biennial plants. 

 Perennial plants from the tropical regions, as they will be 

 killed by frost in the north, must here be grown as annuals, 

 if they are to be grown at all. 



The other classification depends upon the stems of the 

 perennial plants. If they 

 are soft and juicy, so that 

 they are killed by the win- 

 ter cold, and die to the 

 ground, even though the 

 roots live on, then the 

 plants are called her- 

 baceous. Such are the 

 larkspur and rhubarb. If 

 the stems are hard, and 

 live through the winter, 

 they are called woody. 

 Such are all shrubs and 

 trees. 



These classes of plants 

 are easily understood, though their names may be hard to 

 memorize at first. But every new subject has its special 

 words which must be learned. And if we are to understand 

 about a plant, we need to know whether it is hardy or tender, 

 annual or perennial, herbaceous or woody. 



As now we face the beginning of the garden season, we see 

 first a period in which it will pay to start plants in the house, 

 during which they will grow to such a size that they can 

 finally be set outdoors, and will then yield quickly. 



During this period we are likely to start the hardy plants 

 first, because they can first be set outdoors. We start the 

 tender plants later, because they must later be set outdoors. 



FIG. 61. Lettuce, a hardy annual vege- 

 table, will withstand frost. 



