HOUSTONIA HYACINTHUS. 255 



then thrown away and their places supplied by other 

 plants. Cuttings are generally made in late winter or 

 spring for the next winter's bloom. These cuttings are 

 slips (page 65) of the growing wood. See the various 

 species, under their respective heads. 



Houstonia. Rubiacea. 



Seeds. May also be increased by carefully made divi- 

 sions in autumn or spring. 



Hovea, Poiretia. Leguminosa. 



Propagation is best effected by seeds, sown in well- 

 drained pots of sandy peat soil in spring, and placed in 

 a gentle bottom heat. Cuttings are difficult to strike. 



Hovenia. Rhamnacece. 



Increased by seeds. Root cuttings are also used. Ri- 

 pened cuttings should be placed in sand, under a hand- 

 glass. 



Hoya (Honey Plant, Wax Flower). Asclepiadacea. 



For layering, good-sized shoots should have a few of 

 their leaves removed, and should then be put in pots of 

 soil until rooted. The plants may afterwards be grown 

 on, and repotted according to their strength. Cuttings 

 may be taken in spring or later in the year, from shoots 

 of the preceding summer's growth, and placed in a com- 

 post of peat and sand, and plunged in bottom heat in a 

 frame. A slight shade and careful watering will be neces- 

 sary. H. bella does best when grafted on a stronger 

 growing sort. 



Huckleberry. See Vaccinium and Whortleberry. 



Humulus (Hop). UrticacecE. 



It may be propagated by seeds, or by divisions in spring. 

 Ordinarily, however, the species is increased by hard- 

 wood cuttings of two-bud lengths from the best old 

 shoots, and made in spring. Leave the top bud just 

 above the ground. 



Hyacinthus (Hyacinth). LiliacecB. 



Seeds are employed for the production of new varieties. 

 These are sown the same season they mature, in light, 

 sandy soil, and are covered not more than a half-inch 

 deep. In four or five years, or sometimes even longer, 

 the bulbs will be large enough to flower. Varieties are 

 perpetuated by means of the bulbels, which form freely 



