BIAEUM 



THE BULB BOOK 



BIGNONIA 



The bulbs are best planted in a 

 compost of sandy peat and loam in 

 about equal proportions, and may be 

 grown in a greenhouse in the coldest 

 parts of the Kingdom, or in the 

 warmest places in sunny spots against 

 a south wall. During the growing 

 season — that is, during the spring and 

 summer months— the soil should be 

 kept fairly moist when grown in 

 pots, afterwards withholding water 

 as the plants show signs of going to 

 rest. Propagation is effected by 

 means of offsets from the older bulbs 

 in spring. 



BIARUM (bis, twice ; Arum, Arum). 

 Nat. Ord. Aroidese.— A small genus 

 of tuberous-rooted herbaceous plants 

 closely related to the Arums, and 

 having linear oblong, or lance-shaped 

 leaves with long slender stalks, all 

 natives of Palestine and the Medi- 

 terranean region. The flower-stalks 

 are short or almost absent: the 

 spathes soon wither. The plants are 

 aU hardy, but like warm, sunny spots 

 in any good and well-drained garden 

 soil. They are more curious than 

 beautiful, and consequently more 

 appropriate in botanical collections 

 than in the ordinary flower-border. 

 They are increased by separation of 

 the offsets from the older tubers in 

 spring. The best-known species is 

 B. tenuifolium (also known as £. 

 graminewm, B. constrictum, and Arum 

 tenuifolium), with dark brownish- 

 purple spathes (Bot. Reg. t. 512). 

 Other kinds, all with blackish-purple 

 spathes, are B. cmgv^statu/m, B. car- 

 dvjdiorwm, B. crispvlum, B. Kotschyi, 

 and B. Pyrwmi. 



B. exlmlmn, is a native of W. 

 CUicia, vdth broad, simple leaves, and 

 spathes dark purple on the upper 

 side, and green spotted with red on 

 the under side {Gard. Chron. 1898, 

 xxiii. 126, f. 49, as Ischarum). 



BIDENS {his, twice ; dens, a tooth ; 

 in allusion to the seeds). Nat. Ord. 

 CompositaB. — This is a large genus, 

 having over one hundred species of 

 more or less weedy plants with 

 opposite leaves, once, twice, or thrice 

 pinnately cut, and solitary flower- 

 heads. 



B. datalloldes is a native of Mexico, 

 where it is found at an elevation of 

 over 8000 ft. It is a perennial about 

 2 ft. high, with Dahlia-like, tuberous 

 roots, pinnate leaves having three to 

 seven leaflets, and solitary flower- 

 heads about 3 ins. across, the ray 

 florets varying in colour from white to 

 pink, purple, and rose. 



This little-known plant flourishes 

 in milder parts of the Kingdom in 

 ordinary good garden soil, and may 

 be easily propagated by division of 

 the tuberous roots and by means of 

 seeds, which are freely ripened in 

 favourable parts. In cold or bleak 

 places the plants may be treated 

 exactly like Dahlias, the tubers 

 being lifted and stored in frost-proof 

 places in winter. 



BIGNONIA (after the -466/ Bignon, 

 librarian of Louis XIV.). Nat. Ord. 

 Bignoniacese. — This genus contains 

 about 120 species of shrubby plants 

 with more or less climbing stems. 

 The one mentioned here is remark- 

 able for its long, irregularly shaped, 

 tuberous roots, viz. : — 



B. sequinoctialls {B. Unguis). — A 

 native of Guiana, with climbing stems, 

 smooth, opposite leaves in pairs, and 

 during the summer months bearing 

 clusters of irregularly bell-shaped 

 yellow flowers on the ends of the 

 young shoots. 



This species requires stove or warm 

 greenhouse treatment, and flourishes 

 in rich, light soil, and plenty of 

 moisture during active growth. Its 

 shoots may be trained up pillars or 



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