ECONOMIC PLANTS 



257 



owing to its growing in clusters, it is commonly called 

 grapefruit. It requires about the same conditions and 

 culture as the or- 

 ange, except that 

 it demands a 

 higher tempera- 

 ture, being slightly 

 less hardy. Dif- 

 ferent varieties are 

 propagated by 

 budding on pomelo 

 or orange seedlings. 

 The Florida Ex- 

 periment Station 

 recommends the 

 exclusive use of 

 commercial ferti- 

 lizers as they cause 

 the trees to fruit 

 more heavily, to 

 produce a fruit of 

 better quality, and to maintain a healthier condition. 

 Fertilizers should be applied twice a year, just before the 

 commencement of growth and again in summer. Some- 

 times a third application in the fall is advisable, as the 

 roots grow during winter seasons. 



Berries. Strawberries. Certain varieties of the 

 strawberry commonly grown in the United States 

 bear only pistillate flowers ; that is, no pollen is formed 

 in its blossoms. (See page 148.) This requires that 

 some variety bearing pollen-.forming flowers be set 

 out with it, or no fruit will result. It has been found 

 that one row of the latter to every three or four of the 

 M. & H. AG. 17 



FIG. 132. Grapefruit. 



