Trumpet Honeysuckle

Size, growth and what to expect

Trumpet honeysuckle grows fast, nearly three feet a year in our growth estimator. It is a twining vine that climbs 10 to 20 feet up a support or sprawls as a ground cover, and one plant fills 3 to 6 feet of fence. It keeps its leaves through winter in the Deep South and drops them farther north.

Whorls of red trumpets, yellow inside and 1.5 to 2 inches long, open from March into July, with a few more later. Hummingbirds are their main pollinators. Red berries about a quarter inch across ripen from July into September, and robins, finches, thrushes and quail eat them. Its leaves feed the caterpillars of the spring azure butterfly and the snowberry clearwing moth.

It grows wild from Connecticut south to Florida and west to Oklahoma and Texas, in woodlands, at forest edges and along streams. Vines planted in gardens have also gone wild in Maine, West Virginia, Missouri, Iowa and Kansas.

How to grow Trumpet Honeysuckle

Trumpet honeysuckle flowers best in full sun and grows in part shade, though it blooms poorly in heavy shade. It wants a moist, well-drained soil rich in humus. Acid or limy ground suits it, and once rooted it rides out occasional drought, though not dry sand. Sun and moving air keep powdery mildew down. It tolerates salt, which suits it to coastal gardens. Its twining stems cannot grip a flat wall, so give it a trellis, an arbor or a fence. Set the support 3 feet from a wall, and set plants 3 feet apart. It burns readily, so where wildfire is a risk keep it out of the planting zone next to a house. At its size it can go within 15 feet of overhead wires.

Saplings ship bare-root or potted. Plant them dormant, from leaf fall until bud swell, in a hole wider than the roots and no deeper. Set the crown at the soil line, put the native soil back in, and keep the mulch clear of the stems. Tie the first shoots to the support until they twine on their own. Pick the berries as they turn red, and clean the seed out at once. Sow it outdoors in fall, a quarter inch deep, under a light straw mulch. For a spring sowing, chill the seed damp in the refrigerator for two to three months first. Softwood cuttings root easily too.

Water weekly through the first summer if rain is short. Deer browse the leaves and stems, so cage young plants where deer are many. Skip high-nitrogen fertilizer, which feeds leaves at the expense of flowers. Prune right after the spring bloom to shape it. Heading it back each year keeps leaves low on the support instead of only at the top.

Each flower carries both male and female parts, so there are no male and female plants to pair. Hummingbirds carry its pollen, and so do clearwing moths and bumble bees. Aphids gather on the new shoots in spring, and a spray of water knocks them off. Powdery mildew and leaf spots can appear in hot, humid summers. Songbirds eat the berries, but they are toxic to people.