126 THE PRACTICAL GARDEN -BOOK 



Hedges should be trimmed the year after they are set, 

 although they should not be trimmed very closely until they 

 reach the desired or permanent height. Thereafter they 

 should be sheared into the desired form in spring or fall. 

 If the plants are allowed to grow for a year or two without 

 trimming, they lose their lower leaves and become open and 

 straggly. Osage orange and some other plants are plashed 

 that is, the plants are set at an angle rather than perpen- 

 dicularly, and they are wired together in such a way that 

 they make an impenetrable barrier just above the surface of 

 the ground. 



Helianthus. See Sunflower. 



Helichrysum. These are perhaps the most 

 popular of the Everlastings (which see), having Targe flowers 

 of several colors. They grow readily from seed, blooming 

 from July to October. Height 10 inches to 2 feet. Should 

 be planted or thinned to stand 18 inches apart. 



Heliotrope. A universal favorite house or 

 border plant, growing readily from cuttings or seeds, and 

 producing quantities of fragrant violet, purple or white 

 flowers. One of the best methods of cultivation is to set a 

 strong plant in the border and peg the new growths to the 

 ground, where they will root and form a perfect mat, flower- 

 ing profusely during the fall months until frost. They 

 will endure the temperature of a living room well if the 

 room is not too dry. Red spider is a natural enemy of the 

 Heliotrope, and when once it obtains a foothold is a very 

 difficult pest to manage, but frequent syringing with water 

 will keep it in check. A light, rich soil and an abundance 

 of heat are their requirements. Height 1 to 3 feet. Propa- 

 gated by cuttings or layers. 



Hellebore (White Hellebore) is often used for 



the killing of currant-worms and other insects (see Currant}. 

 It is not so poisonous as the arsenites, and therefore is to be 

 preferred when it is necessary to apply a poison to nearly 



