294 Landscape Gardening 



Tender Summer-flowering Bulbs 



Dahlias (Dahlia sp.). Dahlias are essentially flower- 

 garden subjects, requiring rich soil and careful culture. 

 Usually they do not give good results among other plants 

 unless they have considerable space, as the plants require 

 plenty of air and sunlight. They thrive in any good soD 

 that has been enriched, although a sandy soil is preferred. 

 Single tubers are best for planting, which may be done two 

 weeks before danger of frost is over. Earlier than this 

 may result in the shoots being killed, as they are tender. 

 This, in the latitude of New York City, would be about 

 May i st. The roots should be planted from 6 to 8 

 inches deep, although if the soil is heavy, it is best not to 

 fill the soil so that the surface is level, but gradually work 

 the soil around the plants as they increase in height. A 

 common method of culture is to cover the tubers 2 or 

 3 inches deep in the bottom of the furrows, and when the 

 shoots appear, remove all but the strongest one, which is 

 pinched as soon as two pair of leaves are formed. This 

 causes the plant to branch below the surface of the ground, 

 thus making staking unnecessary. The plants, having the 

 entire strength of the root and soil concentrated in one shoot, 

 grow very vigorously. Thorough cultivation should be 

 given. Deep tillage is beneficial until plants begin to bloom, 

 when light stirrings of the surface should be made. If the 

 plants cease blooming, a small handful of bone meal and 

 nitrate of soda should be given. The most serious insect 

 pest is the tarnished plant bug. When frost has killed the 

 plants, dig the tubers, allow them to dry for a few hours, and 

 store in a frost-proof cellar. If the air of the cellar is dry, 

 pack the roots in dry sand or in sawdust to prevent shrivel- 

 ling. Varieties of dahlias are propagated by division of the 

 clumps and also by cuttings taken from tubers started in 



