252 Principles of Plant Culture. 



especially in varieties that form seed. The removal of 

 flower- buds from cuttings in the propagating bed encour- 

 ages the formation of roots. Topping tobacco and rhubarb 

 plants (416 c) causes the leaves to grow larger, and of 

 onion plants stimulates growth of the bulbs. De-iasseling 

 corn encourages growth of the ears (416 d). Thinning 

 fruit on plants that incline to overbear, causes the re- 

 maining fruits to grow larger (416 i, 160). 



428. b Pruning for Flowers or Fruit. Since checking 

 growth tends to stimulate the formation of flower- buds 

 (135 b), we encourage flowering in plants that incline to 

 luxuriant growth, by pruning which tends to check 

 vigor. This may be accomplished, 



(a) By pinching the terminal buds during the growth 

 period, as is often practiced upon tardy-bearing fruit 

 trees or upon seedling fruit trees of which it is desirable 

 to soon learn the quality of the fruit. To be successful, 

 it must be performed rather early in the growing season, 

 and before the time for the formation of flower- buds. 

 The blossoms do not usually appear until the season fol- 

 lowing the pinching. 



With plants that flower at the terminal growing points 

 of the principal branches, as the spiraeas, hydrangeas, 

 rhododendrons etc., pinching to promote flowering is 

 not advisable, as it tends to reduce the size of the flower 

 clusters. 



(b) By cutting back the new growth. Woody plants 

 that flower on stems more than one year old, as the 

 apple, pear, currant etc., when grown on rich or well 

 cultivated ground, or that have been too severely pruned, 

 often tend to produce an excess of new wood with a very 



