Crossvine (Bignonia capreolata) is a vigorous, fast-growing woody vine known for its attractive trumpet-shaped flowers, typically orange, yellow, or deep orange-red. It quickly covers structures with lush foliage, making it a popular choice for gardeners. The name comes from the cross-shaped pith visible when the stem is cut.
Site Selection and Planting
Crossvine thrives in full sun to partial shade, with optimal flowering in full sun. It adapts to various soil types but prefers well-draining, organically rich soil with a pH between 6.8 and 7.2. While it tolerates brief standing water, good drainage is preferred to prevent issues.
When planting, a sturdy support structure like a trellis, fence, pergola, or arbor is necessary, as the vine uses branched tendrils with adhesive disks to cling and climb. Plant in early spring or fall. Dig a hole two to three times wider and as deep as the root ball, ensuring the top is level with the surrounding soil. Backfill, gently firming to remove air pockets, and water thoroughly.
Ongoing Care
During its first growing season, crossvine needs consistent moisture to establish a strong root system. Watering deeply once a week, saturating the root zone, is generally sufficient. Once established, crossvine becomes drought-tolerant, but benefits from occasional deep watering during extended dry periods.
Crossvine is not a heavy feeder but benefits from fertilization. Apply a balanced slow-release fertilizer (e.g., NPK 8-5-5 or 10-10-10) in early spring before flowering and again after blooms fade to promote healthy growth and flowering. Avoid over-fertilizing, which can lead to excessive foliage growth at the expense of blooms.
Apply a 1 to 2-inch layer of organic mulch (e.g., wood chips or shredded bark) around the plant’s base. This conserves soil moisture, suppresses weeds, and regulates soil temperature. Mulching also contributes organic matter as it decomposes, further benefiting the plant.
Pruning and Training
Pruning crossvine maintains its size and shape, encourages denser growth, and promotes abundant blooms. It also removes dead, damaged, or overgrown branches. Since crossvine blooms on old wood, prune immediately after its main flowering period in late spring or early summer.
When pruning, thin crowded stems to improve air circulation and shape the vine. Heading back overgrown areas controls its vigorous growth, which can reach 30 to 50 feet. Training involves guiding young shoots onto the support structure using twine or gentle ties until they establish their own grip with adhesive tendrils.
Common Issues and Winter Protection
Crossvine is generally resistant to most insect pests and diseases, making it low-maintenance. However, issues like black mildew, blight, or leaf spot can occur, often linked to poor air circulation or insufficient sunlight. Keeping the plant well-spaced and ensuring adequate light mitigates these problems.
Crossvine is hardy in USDA Zones 6 to 9, and may survive in Zone 5. In colder parts of its range, especially Zone 5, the foliage may turn reddish-purple and drop in winter, and stems might die back to the ground. Despite this, roots are typically hardy and will sprout new growth in spring. Applying winter mulch around the plant’s base provides additional insulation for roots in colder climates.