Kalanchoe blossfeldiana, the florist kalanchoe, is a native of northeast Madagascar that found its way into European horticulture in the 1920s through the collecting efforts of Robert Blossfeld, whose name it now carries in its botanical epithet. Compact, upright, and multi-branched, it grows from six to eighteen inches tall and carries thick, fleshy, dark green leaves with scalloped edges. The flowers are tiny but numerous, massed in large umbels above the foliage in bold shades of red, orange, yellow, pink, or white. Single and double-flowered cultivars exist, and the blooms are long-lasting enough to make this one of the more satisfying windowsill plants available.

Flowering requires a specific light discipline: six to eight hours of bright light daily through most of the year, then fourteen hours of complete darkness each day for at least six weeks in fall and winter to trigger the bloom cycle. Those willing to manage this will be rewarded with spring flowers that last several weeks, and deadheading spent blooms encourages the plant to produce more. Outdoors it is hardy only in zones 10 to 12, where it works well as groundcover or in raised planters; elsewhere it belongs on a patio in summer and a windowsill in winter. Allow the soil to dry between waterings and use a cactus or succulent potting mix to avoid the root rot that is its most common complaint.