FIG. 48. AGAVE YUCCÆFOLIA.
A. yuccæfolia (Yucca-leaved).* fl. greenish yellow, 1¼in. to 1½in. long, in a dense spike 6in. to 15in. long, about 14in. in diameter, sessile, solitary, or in pairs; scape 12ft. to 20ft. high. l. twenty to forty in a dense, shortly-stemmed rosette, linear, much recurved, 1½ft. to 2½ft. long, ¾in. to 1in. broad at the middle; face deeply channelled, dull, rather glaucous green, with a pale band down the centre, the tip not at all pungent, the back broadly rounded, edge entire, or obscurely serrulate. Mexico, 1816. A most distinct species. See Fig. 48.
AGERATUM (from a, not, and geras, old; in reference to the flowers being always clear). SYN. Cœlestina. ORD. Compositæ. This genus includes several American species, for the most part half-hardy annuals and biennials; or, if the seed is not allowed to ripen, they become perennials. Involucre cup-shaped, of many imbricated linear bracts; receptacle naked. Leaves opposite. A light rich soil is most suitable. Very easily increased by cuttings or seeds; if required true, the former is the only sure method of propagation. To grow large plants for greenhouse decoration, sow the seeds in January, in heat, in sandy soil, barely covering them. As soon as the young plants are large enough, prick them off into thumb pots, and keep in heat till they grow freely, then place them into a cooler house. Transfer into larger pots as soon as the others are full of roots, until they are finally shifted into 10in. or 12in. pots. When these are full of roots, the plants should be watered with liquid manure twice a week, and they soon flower well, making fine specimens. During hot weather especially, they should be well syringed with clear water daily, to keep down red spider. The plants required for bedding (for which purpose the dwarf garden varieties are mostly used) should be raised about the same time, kept in small pots, gradually hardened off, and planted out in the middle or end of June. Cuttings of all the varieties strike readily in heat, treated like most soft-wooded plants, and, when rooted, may be managed as recommended for the seedlings.
A. Lasseauxii (Lasseaux's). fl.-heads rose-coloured, small, disposed in corymbose heads. Summer. l. lanceolate-elliptic. h. 1½ft. to 2ft. Monte Video, 1870. A much-branched plant, requiring greenhouse protection in winter, and suitable for planting out in summer.
A. latifolium (broad-leaved). A synonym of Piqueria latifolia.
A. mexicanum (Mexican).* The commonest and most useful species, with a profusion of lilac-blue flowers. h. 2ft. Mexico, 1822. When used for bedding purposes it may be pegged down like the Verbena, or be allowed to grow its full height. Several very dwarf varieties of it have originated under cultivation, which supersede the species for bedding, the best of which are:—CUPID,* rich blue, very dwarf and floriferous; IMPERIAL DWARF, about 9in. high, with porcelain blue flowers; LADY JANE, of the same colour, very free; QUEEN,* silvery grey, about 9in. high; SNOWFLAKE,* white, very free and showy; SWANLEY BLUE,* very deep blue, 6in. to 8in. high. There is also a white-flowered variety of Mexicanum, which is very showy; and a variegated form, sometimes grown for the sake of its pretty foliage.
AGGLOMERATE, AGGLOMERATED. Collected into a heap or head.
AGGLUTINATED. Glued together.
AGGREGATE, AGGREGATED. Gathered together; usually applied to the inflorescence.
AGLAIA. (mythological: from Aglaia, the name of one of the Graces, and given to this genus on account of its beauty and the sweet scent of the flowers). ORD. Meliaceæ. Stove evergreen trees or shrubs having very small flowers, disposed in branched axillary panicles. Leaves alternate, trifoliate, or impari-pinnate. There are several species, but the undermentioned is the only one worth growing yet introduced. It thrives well in a mixture of turfy loam and peat. Young cuttings ripened at the base, and taken off at a joint, will root in sand under a hand glass, in heat.
A. odorata (sweet-scented). fl. yellow, small, in axillary racemes, very sweet-scented, said to be used by the Chinese to scent their teas. February to May. l. pinnate, with five or seven glossy leaflets. h. 8ft. to 10ft. China, 1810.