BLESSED THISTLE. See Cnicus benedictus, properly Carbenia benedicta.
BLETIA (in honour of Don Louis Blet, a Spanish botanist). ORD. Orchideæ. A large genus of, for the most part, stove terrestrial orchids. Flowers purple or whitish, in terminal racemes. Leaves narrow, grass-like. Pseudo-bulbs round, flattened. The flowers are freely produced when the plants are thoroughly established, and are valuable for bouquets, as well for their pleasing colour as for the time they last in perfection. Bletias thrive best in a compost of loam and leaf mould. About 2in. of crocks, covered with a layer of moss, should be placed in the bottom of the pot, which should be filled to within 1in. of the top with soil. The bulbs should then be inserted, and just covered. A good supply of water during the growing season is necessary, and only a moderate amount of heat. After growth has ceased, a period of rest is required, during which time very little water should be given. Propagation is effected by divisions, which should be made after the plants have finished flowering, or previous to their starting into growth.
B. campanulata (bell-shaped). fl. deep purple, with a white centre, lasting a considerable time in perfection. Mexico.
B. florida (florid).* fl. pale rose-coloured; lip not spurred. July and August. h. 2ft. West Indies, 1786. A very pretty species. (B. R. 1401.)
B. gracilis (slender). fl. pale greenish-white; sepals and petals nearly equal, lanceolate, acuminate; lip red and yellow; scape simple. l. oblong, lanceolate, plicate. h. 1½in. Mexico, 1830. (B. R. 1681.)
B. hyacinthina (Hyacinth-like).* fl. purple, racemose; lip not spurred, beardless; scape about as long as the leaves. March to June. l. lanceolate. h. 1ft. China, 1802. This pretty species has proved to be quite hardy. (Garden, Nov., 1879.)
B. patula (spreading-flowered). fl. purple, spreading; scape tall, branched. March. l. lanceolate. h. 2ft. Hayti, 1830. (B. M., 3518.)
B. Shepherdii (Shepherd's).* fl. on branching spikes, purple, marked down the centre of the lip with yellow. Winter. l. long, lanceolate, dark green. Jamaica, 1825. (B. M. 3319.)
B. Sherrattiana (Sherratt's).* fl. about a dozen on a spike, rich rosy purple; petals very broad, twice the breadth of the sepals; lip deep purple in front, marked with white and yellow down the centre. l. three to four-plicate. Pseudo-bulbs depressed. New Grenada, 1867. (B. M. 5646.)
B. verecunda (modest). fl. purple; lip not spurred. January. h. 3ft. West Indies, Mexico, &c., 1733. (B. M. 930.)
BLIGHIA SAPIDA. The Akee Tree. This is now included under the genus Cupania (which see).
BLIGHT, or BLAST. Applied to various diseases of plants which are caused or accelerated either by the presence of parasitic fungi or insects, or by atmospheric influence. Blight generally proves fatal to the whole or part of the subject attacked.
BLIND. A term applied to plants which fail to produce central buds. The defect is frequently noticeable in the Cabbage, and other plants of the Brassica tribe; and is, perhaps, mainly due to the attacks of insects in a very early stage. Great care should therefore be exercised in keeping the seed beds clear of insect pests, by the application of ashes, lime, and soot, or spent hops.
BLOOD FLOWER. See Hæmanthus.
BLOODROOT. See Sanguinaria canadensis.
BLOOM. A fine powder-like substance found on Grapes, Cucumbers, Plums, &c., and varying in colour in the different subjects. It should be carefully protected, as it improves the appearance of the fruit. The term is also generally used—although incorrectly—as the plural of blossom.
BLOSSOM. The flower of a plant, or the essential organs of reproduction, with their appendages.