Bottom Heat. 



( 134 ) 



Bouvardia 



Principal Species : 



Lunaria, The Common Moonvvort, fertile fronds, 

 4" to 5" ; sterile fronds, 2" to 3". 



ternatum. fertile fronds, ti" to 12" ; sterile 

 fronds, 4" to 12". There are several varieties; see 

 second list. 



virginianum, fertile and sterile fronds, 6" to 18". 

 This species requires a little protection in win. in 

 very bleak situations. Lanuginosum is a very 

 woolly var. 



Other Species : 

 australe, a geographical obliquum, a var. of ter- 



var. of ternatum. natuui. 



daucifolium, 9" to 18", subcaruosum (ace dauci- 



grh. (*?/. subcaniosum). folium), 



limarioides, a var. of 



tematum. 



BOTTOM HEAT. 



Now generally supplied to plants by hot-water 

 pipes, but the old-fashioned manure pit or hotbed 

 with its warm, moist, growing atmosphere is still 

 a power to be reckoned with. (See Hotbeds and 

 Heating.) Bottom heat is applied to start plants 

 or seeds into growth, and to cause cuttings to 

 emit roots ; and should, as a general rule, be about 

 5" higher than the temperature of the surrounding 

 atmosphere. 



BOUCEROSIA. 



Succulent greenhouse perennials (ord. Ascle- 

 piadeas), closely allied to Stapelia, and needing 

 similar cultural attention. The plants flower 

 freely, and the flowers are very fleshy, strongly 

 reflexed, and of a curious appearance, with strong 

 markings. The stems and branches are four- 

 sided, and the acute angles with which they are 

 furnished are more or less spiny. 



Principal Species : 



europasa, 4", sum., pur., br., yel. (sym. Apter- 

 anthes gussoniana and Stapelia gussoniana). 



maroccana, 4", sum., red pur. with yel. concentric 

 markings. 



BOUCHEA. 



Stove and greenhouse herbs and sub-shrubs (ord. 

 Verbenaceie), very rarely met with in cultivation, 

 iind of no great value. They may be increased by 

 cuttings under glass in spring in a gentle heat, and 

 need a compost of loam and peat. 



Principal Species : 



cuneifolia, 4', Ap., wh., grh. shr. (syn. Chascanum 

 cuneifolium). 



pseudo-gervao, 2' to 5', Sep., pur. wh. throat, st. 



BOUGAINVILLE A. 



Description, Showy shrubby climbers (ord. 

 Nyctaginese), requiring a warm greenhouse or stove 

 temperature. The flowers are small and green, but 

 the bracts are large and showy, and are commonly 

 regarded as the real flowers. The plants are of 

 very easy culture, and once they attain maturity 

 flower regularly and well each year. 



Propagation. By cuttings of tips of the half 

 ripened wood inserted in very sandy soil in brisk 

 bottom heat in a close frame. 



Soil. The bulk should be of good loam, with a 

 sixth part each of leaf soil and rough grit or sand. 



Other Cultural Points. Bougainvilleas may be 



Bol.ryodendruni (sue Meryta}. 

 liottte tiinird (see Lagetuiria). 



grown either in pots or planted out in specially 

 prepared borders. Pot culture is not to be recom- 

 mended, however, for the tied-in shoots are stiff 

 and formal, although they may flower well. The 

 border may have a total depth of 2', of which G" 

 should be drainage. The main branches should 

 be trained to the roof, and the smaller shoots 

 allowed to hang down with their burden of flowers. 

 There is a close similarity between the treatment 

 required by Bougainvilleas and that given to Vines, 

 viz. plenty of water during the growing season, 

 less in the autumn, and very little, if any, in the 

 winter. The pruning consists in closely spurring 

 back each autumn the shoots made during the 

 previous summer. Like Vinos, also, a little dis- 

 budding is needed in spring when the young 

 growths begin to push. Frequent syringing will 

 help the swelling buds considerably. Liquid 

 manure may be given in the growing season, 

 but the roots must not be excited by stimulants 

 during the resting period. 



The most troublesome insect pests are mealy bug 

 and thrips, but they may be kept under by the 

 remedies which will be advised under their names. 



Principal Species : 

 glabra, sum., bright ro. 



Coker Court var. 



sanderiuiia, sum., ro., 

 very free, good for sub- 

 tropical bedding. 



larger than those of 

 glahra. 



superba, sum., rich 

 ro., very large, the 

 finest of all. 



speciosa (.> spcctabilis). variegata. 



spectabilis, lil, ro., bracts 



Other Species : 



refulgens, sum., St., pur., mauve. 



BOUSSINGAULTIA. 



Half-hardy plants (ord. Chenopodiacese) with 

 tuberous roots, pretty, but little known. They 

 may be propagated by the tubercles, which are 

 borne in numbers upon the stems. They like a 

 light, rich soil, and a well-drained position, where 

 they can get plenty of sun. This especially applies 

 to baselloides. 



Principal Species : 



baselloides, 2' to 8', aut., wh. passing to blk., 

 fragrant. An elegant little trailing plant, doing 

 best in a grh. 



cordata, very close to baselloides. 



Lachaumei, St., ro. 



BOUVARDIA. 



Description. Evergreen shrubs (ord. Rubiacese) 

 requiring the temperature of a warm greenhouse. 

 The flowers are very freely produced, and of bright 

 and varied hues. Bouvardias are commonly grown 

 as winter flowering plants, and they are among the 

 most useful and easily grown subjects available for 

 the purpose. They may also be utilised as summer 

 bedders, flowering profusely towards the end of the 

 summer. Few of the species, with the exception 

 of Humboldtii corymbiflora and triphylla, are to 

 be met with in cultivation, but there are many 

 beautiful hybrids, for which see special list. 



Propagation. By cuttings of the young shoots 

 taken off in spring with a heel of the old wood. 

 After the plants have finished flowering they should 

 be cut hard back, placed in heat, and frequently 

 syringed. They will then break freely into growth, 

 and furnish plenty of cuttings, which are best taken 

 off when they are about 2" long. A gentle bottom 

 heat, and an atmospheric temperature of <iO c , will 

 ensure quick rooting. Also by root cuttings. 



