ABSTRACT
Coleus, a genus of the Mint Family, includes annual or perennial herbs with fancy leaf colors and variegations. Flowers develop on terminal racemes. C. blumei Benth. is the most frequently cultivated Coleus and exists in many varieties. The genus originated in Old World tropics. C. lanaginosus Hochst, responded like an absolute LDP to daylengths of 24, 16, and 10 hr provided by fluorescent and incandescent lamps. C. blumei was considered by Laibach to be a LDP on the basis of its normal flowering time in greenhouse, although from such observations he felt that within the numerous cvs of C. blumei there are graded levels of the LD character. Grafts of single leaves have been used by Jacobs, both within Coleus species and between them, to provide evidence for floral inhibitors and floral stimulators. Excision of all axillary buds and branches caused faster flowering of the Princeton clone of C. blumei and compensatory growth of the leaves on the main shoot.
