Seeds and cuttings I collect around North Carolina, what they turned out to be, and how to grow them for a NC Piedmont native-plant nursery.
Bignonia capreolata · Bignoniaceae
Reddish-orange trumpets high in bottomland trees in April. Flat brown pods come off in late summer.
Community photos of Bignonia capreolata to study before I head out: leaf, flower or bract, ripe fruit, bark, whole plant.
Native throughout the NC Coastal Plain and Piedmont, chiefly in bottomlands; infrequent in the Mountains. Present but often overlooked in Person County bottomlands
Best bet: Cuttings are the higher-percentage and truer-to-form route: semi-hardwood stem cuttings in June–July under mist with rooting hormone around 3,000–5,000 ppm root in 4–8 weeks. Root cuttings and simple layering work too. Seed is nearly as easy and needs no stratification and no scarification: collect just-browning pods before dehiscence, dry indoors in a paper bag until they crack, shake out the winged seeds, and sow fresh in fall or spring for about 90% germination in roughly 3 weeks. Seed only keeps about a year refrigerated, so there is no point stockpiling.
A Piedmont native at home in heavy clay, heat and humidity. Sun to part shade, drought-tolerant once established, USDA zones 5–9. It blooms hardest in full sun; shaded plants stay leafy but flower and fruit poorly, so scout sunny edges for seed. It is vigorous, climbing 30–50 ft and spreading by both seed and root suckers, which is why NC Extension rates it weedy and aggressive. Give it a stout support and pull suckers to keep it in bounds. It is a well-behaved native rather than an exotic invasive, but do not plant it expecting a tidy, non-suckering vine.
Each look-alike with the one character that settles it. Tap a photo to zoom.
Pinnately compound leaves with 7–11 toothed leaflets and no tendrils; it climbs by aerial rootlets and blooms mid-summer rather than spring
Simple entire opposite leaves with the uppermost pair fused around the stem, and twining stems. No compound leaves, no tendrils
Simple leaves and pure-yellow flaring flowers on a slender twining stem. Never the two-leaflet-plus-tendril leaf
Alternate leaves of three leaflets and fuzzy aerial rootlets. Never opposite, never tendrils
April and May are when crossvine is easiest to pin down. Clusters of two-inch reddish-orange to brick-red trumpets, yellow-throated and faintly mocha-scented, light up forest edges and the crowns of bottomland trees. It climbs high on disc-tipped tendrils, so the flowers are usually overhead. I scan trunks and fence lines at eye level first, then look up. Off bloom, the semi-evergreen foliage is what gives it away in winter: glossy paired leaflets flushing purple-bronze in the cold while everything around it is bare. What I'm looking for is a moist woodland or floodplain edge with a woody vine gripping bark by tendrils.
Flowers finish by late May. The flat bean-like capsules mature through late summer, dry light brown, and persist into fall. Collect Aug–Oct, once the pods turn brown but before they split, because they dehisce and scatter stacked papery winged seeds; the margin here is days, not weeks. Dry pods in a paper bag until they crack, shake the seed free, and sow fresh. No stratification or scarification, and expect around 90% germination in about three weeks. Seed is short-lived, viable only about a year even refrigerated, so stockpiling wastes it. Worth remembering that vines in dry upland shade often won't fruit at all, so sunny moist-site plants are the ones to target. For insurance, crossvine roots easily from semi-hardwood cuttings taken June–July under mist with rooting hormone, in 4–8 weeks, and root cuttings and layering both work. Rooted cuttings or fall-sown seedlings should be trellis-ready inside a season or two.
In Person County, work the bottomland and shoreline woods around Mayo Lake Park and Hyco Lake, plus any creek floodplain or moist fencerow near Roxboro. Farther down the Piedmont, Eno River State Park and Occoneechee Mountain in Hillsborough have reliable riverine hardwood habitat. Favor sunny edges over deep shade. That's where crossvine actually flowers and sets the pods I'm after.