Odontonema strictum

Few plants light a shaded corner the way firespike does. Odontonema strictum raises erect spikes of slender, tubular, scarlet flowers to a foot long from late summer into winter, each spike a torch held above dark, glossy, quilted foliage. The genus name pairs the Greek odous, a tooth, with nema, a thread, for the toothed filaments inside the bloom, and the plant answers to a tangle of common names, firespike, cardinal's guard, and firestick among them, though firespike is the one that sticks.

Native to the humid subtropics of Central America, the firespike carries a rare gift into temperate gardens: real red flowers that hold their color in partial shade, where most scarlet bloomers sulk and thin. The tubular flowers are built for long-tongued visitors, and the late-season spikes pull in hummingbirds and butterflies through the weeks when the border is winding down and the migrants most need fuel.

Firespike also shrugs off trouble that defeats fussier ornamentals, tolerating root-knot nematodes far better than most, a real virtue in the sandy soils of the Deep South. In tropical climates the plant grows as a shrub of three to six feet and rather less across; through the southern United States the top freezes back in winter and the plant returns each spring from a well-mulched crown, so treat the firespike there as a fast, flowering perennial.

Site the firespike where the scarlet spikes can burn against green: a mixed border, a shaded foundation, or a backdrop for lower plants, in a sheltered, sunny to part-shaded spot with well-drained soil and steady water. Pair with heliconias, gingers, and other bold tropical foliage for a hot-climate tableau, or with the purple-flowered cousin, Odontonema callistachyum, whose amethyst winter spikes carry the display through the cooler months. Cut back hard in late winter to keep the plant dense and free-flowering.