734 



THE BOOK OF GARDENING. 



young shoots in spring in the warm pit ; pot on, keep growing, and 

 give plenty of water ; these should flower the same season. Cut 

 back a little after flowering so as to obtain bushy plants, and 

 ripen in the open. Keep cool during the winter and place in 



the warm pit in early spring 

 to start. Flowers in June 

 and July. Soil : loam, leaf- 

 soil, and rotten manure. 

 Feed with liquid manure 

 whilst growing. JV. Oleander 

 has red flowers, and its 

 variety, N. O. album, white. 

 Both do well and make 

 handsome plants planted 

 out. Height 4ft. to 5ft. 



Oleander. — See Nerium. 



Periwinkles. — See 

 Vincas. 



POLYGALA OPPOSITIFOLIA 



and varieties make good 

 pot-plants. Propagate by 

 cuttings of the side-shoots 

 in summer, in a cool pit 

 or frame, and grow in peat, 

 loam, and sand. Cut back 

 a little after flowering, grow 

 on, and ripen in a cool 

 frame. Flowers purple, 

 borne in early summer. 



Rhododendrons play a 

 very important part in fur- 

 nishing the greenhouse during late winter and early spring. 

 There are two sections, (1) those coming from the Himalayas, 

 China, and Japan ; and (2) those coming from the Malay Archi- 

 pelago, Java, and Borneo. 



(1) The Himalayan Section all form large shrubs, and in some 

 cases trees. They may be grown in large pots or tubs, but are 

 best planted out in peat and sand. Give plenty of water, and 

 syringe well when growing. Propagate either by layers in spring 

 or by puttings of young shoots in early summer, just as they 

 are beginning to get firm at the base, and insert almost entirely 

 in sand in the cool pit. Grow cool. Sorts : R. arboreum (Fig. 482), 

 R. barbatum, R. Gibsonii, R. Dalhousia, R, Manglesii, R. niveum, 

 R. grande, R. Aucklandii, R. Jesterianum, R. ciliatum, and 

 R. kewense. These all bear large flowers in big trusses, some- 

 what resembling the hardy varieties of R. ponticum, as also in 

 their habit. See illustration of R. arboreum (Fig. 482). 



Fig. 481. — Nerium Oleander. 



