Trumpet vine (Campsis radicans), hardy in U.S. Department of Agriculture plant hardiness zones 4 through 9, is a woody species grown for its red-orange flowers and feathery, compound leaves. A U.S. Southeast native, it is a vigorous climber, reaching 25 to 40 feet high and 5 to 10 feet wide. The plant climbs by way of its holdfasts, or aerial rootlets. So tying several of its stems to supports is not necessary when you want the plant to grow up a fence. Plant the trumpet vine in a site exposed to full sun for it to flower its best.
Planting the Vine
Dig a planting hole near the fence up which you want a trumpet vine to grow. Make the hole at least as deep as the height of a potted trumpet vine's nursery pot and several inches wider than the pot. The hole's edge closest to the fence should be 6 to 8 inches from the fence's bottom so it does not interfere with footings or supports. Fill about the bottom one-half of the hole with water.
Remove the trumpet vine from its nursery pot, and center the plant upright in the hole. Place the plant at the same soil depth at which it grew in its nursery pot, adding soil to the hole if necessary. Add soil around the plant's root ball, firming the soil when the hole is about three-quarters full of soil and again when the hole is full. Water the soil.
Position a sturdy plant stake or small piece of trellis, which is about 12 inches tall, between the trumpet vine and the fence, angling the stake or trellis so that its top touches the fence. Push the bottom of the stake or trellis 2 to 3 inches into the soil.
Training the Vine
Tie the trumpet vine's strongest shoot, or stem, to the stake or trellis section to guide it toward the fence. Use a flexible plant tie or wire twist tie for that task. Within a few days to one week, the vine will begin its climb toward sunlight, clinging first to the stake or trellis and then to the fence. Observe the growth process until the vine has attached itself to the fence and has grown 6 to 12 inches.
Pinch back, or remove, the tip of the tallest shoot or shoots by using your thumb and forefinger. This procedure encourages the development of side shoots, creating a full, bushy plant.
Pinch back additional new shoots as the trumpet vine continues to grow upward and outward. As the vine grows, its holdfasts will keep it attached to the fence.
Things You Will Need
- Garden gloves
- Shovel or spade
- Tape measure
- Watering can or garden hose
- Sturdy plant stake or small piece of trellis about 12 inches tall
- Flexible plant tie or wire twist tie
- After the trumpet vine reaches the fence's top, it will continue growing. Keep the vine in bounds by pruning it back by one-third to two-thirds after it finishes flowering.
- Discourage root suckers and conserve soil moisture by applying landscape fabric or several layers of newspaper to the area around a trumpet vine's base and covering the material with decorative mulch.
- Wearing gloves is necessary when handling trumpet vine because contact with its leaves causes skin irritation and/or a rash in some individuals.
- Trumpet vine grows rapidly and spreads aggressively, sprouting root suckers that can grow into thickets. Before planting a young trumpet vine that you want to climb a fence, ensure that the fence is sturdy enough to hold the weight of the eventually large vine. Reinforce the fence if necessary.
- Manual of Woody Landscape Plants, Fifth Edition; Michael A. Dirr
- Missouri Botanical Garden: Plant Finder -- Campsis Radicans
- The Times-Picayune: Training Vines Right the First Time
- Hemera Technologies/Photos.com/Getty Images