Justicia spicigera

Mexican honeysuckle is neither a honeysuckle nor a vine but a soft, much-branched shrub of the acanthus family, native from Mexico through Central America to northwestern Colombia and out into the Bahamas and Hispaniola. The common name comes from the flowers: narrow tubes of glowing orange, an inch or more long, carried in loose clusters at the ends of the stems over velvety, grass-green leaves. In frost-free country the plant blooms nearly year-round; in a Southern garden, expect a long show from late spring until frost, with hummingbirds working the flowers from the first tube to the last.

The German botanist Diederich von Schlechtendal described the species in 1832 from Mexican collections. The genus honors James Justice, an eighteenth-century Scottish gardener of famous enthusiasm, and the epithet spicigera means spike-bearing, for the flower clusters. In Mexico the plant goes by a garland of names drawn from Spanish and Nahuatl, among them muicle, muitle, moyotli and trompetilla, the little trumpet, while Maya speakers know the plant as yaxán.

Few garden shrubs carry so much living tradition. Muicle has been used in Mexico since before the Spanish arrived and is still sold by the bundle in markets today. A tea of the leaves is the classic household remedy, taken as a "blood purifier" and for anemia, for upset stomach and dysentery, for menstrual troubles, and for nervios and la tristeza, the low spirits that come with hard times. Modern pharmacologists have taken an interest in that last use: the leaves are rich in the flavonoid kaempferitrin, which has shown antidepressant-like effects in laboratory mice.

The same leaves made Mexican honeysuckle a dye plant. Boiled or simply steeped, they release a pigment that turns the water deep blue to purple-indigo, a color long used for baskets, crafts and cloth and now studied by food scientists as a natural blue. The color shifts with acidity, so a squeeze of lime turns the blue toward red, a small piece of chemistry that delights children and gardeners alike.

In the garden, muicle is easy and generous. Give the shrub a warm spot in sun or light afternoon shade and ordinary well-drained soil, and the plant will fill out quickly into a rounded mound three to five feet tall. In zone 8 the top is usually cut back by hard frost and the plant returns from the roots in spring, so treat this as a woody perennial: mulch the crown in winter, and plant against a south-facing wall in colder gardens. Grow the shrub with salvias, firebush and cupheas in a hummingbird border, or pair the orange with blue plumbago and Salvia 'Indigo Spires' for a hot, high-summer picture.