256 THE NURSERY LIST. 



upon some varieties. These are treated in much the 

 same manner as mature bulbs, or they may be handled in 

 pans or flats. They make flower bulbs in two or three 

 years. To increase the numbers of these bulbels, the 

 bulbs are variously cut by the Dutch growers. These 

 practices are described arid illustrated on pages 28 and 

 29, Figs. 21-23. Hyacinths can be propagated by leaf 

 cuttings. Strong leaves should be taken in early spring 

 and cut into two or three portions, each portion being 

 inserted about an inch in good sandy loam, and given a 

 temperature of about 75. In eight or ten weeks a bulb- 

 let will form at the base of the cutting (see page 60). 

 The lower leaves give better results than the upper ones. 

 These bulblets are then treated in the same manner as 

 bulbels. For Hyacinthus candicans, see Galtonia. 



Hydrangea, Hortensia. Saxifragacece. 



The hardy species are usually propagated by green cut- 

 tings in summer, under glass (see Fig. 75). The tender 

 ones (H. Hortensia, the yar. Otaksa, etc.) are increased 

 by cuttings taken at any time from vigorous young wood, 

 usually in late winter. Layers are occasionally employed, 

 and suckers can be separated from some species. Some- 

 times the hardy species are forced for purposes of propa- 

 gation by cuttage. H. quercifolia is propagated by little 

 suckers or ' ' root pips. ' ' H. paniculata grandiflora can 

 easily be propagated from the young wood, taken in June 

 and planted under glass. 



Hymenocallis. Amaryllidacece. 



Treated the same as Pancratium, which see. 



Ilypericum. Hypericacece \ 



Easily increased by seeds, cuttings, or by strong pieces 

 of the roots of creeping-rooted species. Hard-wooded 

 cuttings, taken in fall, are commonly used. 



Hypoxis. Amaryllidacece. 



Propagation is effected by seeds and offsets. 



Hyssop (Hyssopus officinalis). Labiates. 

 Seeds. Division. 



Iberis (Candytuft). Cruciferce. 



The annuals and biennials are increased by seeds sown 

 in light sandy soil, in spring or autumn. The sub-shrubby 



