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.
Campsis radicans · Bignoniaceae
Orange trumpets on Piedmont fencerows. Trivially easy to grow, genuinely hard to contain.
Community photos of Campsis radicans to study before I head out: leaf, flower or bract, ripe fruit, bark, whole plant.
Native and common across all NC Piedmont counties, and statewide from the Coastal Plain to the lower Mountains. No county gaps around Person Co.
Best bet: Go vegetative. Root suckers and dormant hardwood/root cuttings strike easily: lift a rooted sucker in late winter, or take 4–6 in. hardwood cuttings (Nov–Feb) or softwood cuttings (Jun–Jul, roots in 1–3 wk). For seed, air-dry the capsules, shake out the winged seed, cold-moist stratify ~30–60 days at ~40°F (a short prechill breaks the shallow dormancy and isn't strictly required), then sow warm (70–85°F) in spring. Germination runs around 70%.
Horticulturally about as easy as it gets: a Piedmont native that shrugs off heavy clay, heat, humidity, and drought, with zone 7b/8a well inside its range. The catch is aggression. It suckers into dense colonies from spreading roots and self-seeds freely, aerial rootlets can damage siding and mortar, and the sap causes mild contact dermatitis (cow-itch). Grow it only on a stout freestanding structure well away from buildings, septic lines, and neighbors, or contain the roots with a barrier or a large pot. The risk here is management, not survival.
Each look-alike with the one character that settles it. Tap a photo to zoom.
Only 2 leaflets per leaf, plus a branched terminal tendril. Trumpet vine has 7–11 leaflets and no tendrils
Simple opposite leaves, the upper pair fused around the stem. Trumpet vine is pinnately compound
Leaves of three, and alternate. Both climb by hairy rootlets, so count leaflets and check arrangement instead of relying on the climbing habit
Leaflets glabrous beneath, flowers wider and flaring, corolla only about 1.5x the calyx. Native radicans is hairy on the veins beneath, has narrow tubes 2–3x the calyx, and clings with abundant aerial roots
Trumpet vine advertises itself. Late June through August I'm looking for fist-sized clusters of orange-to-scarlet trumpets flaring off the ends of a coarse, sprawling vine: fencerows, roadside brush, old-field margins, powerline cuts. It wants full sun and disturbed edges, and it does fine on the heavy Piedmont clay that stumps fussier plants. Hummingbirds working a sunny thicket in July usually means trumpet vine. Off bloom I find it by the odd-pinnate opposite leaves draped over a fence, and by the vine gripping wood with masses of short aerial rootlets.
For the nursery I'd skip the seed and take the vine itself. Lift a rooted sucker in late winter, or take 4–6 in. dormant hardwood/root cuttings (Nov–Feb), or softwood cuttings (Jun–Jul), which can root in as little as 1–3 weeks. If I want volume from seed, collect leathery-brown capsules in Sep–Oct just before they split, roughly 2–3 months after bloom. Air-dry them, shake out the winged seed, cold-moist stratify ~30–60 days at 40°F to break the shallow dormancy, then sow warm (70–85°F) in spring for about 70% germination. Seedlings and cuttings both size up fast. Capsules picked green in summer are immature and won't grow; wait for the brown, papery stage.
Around Roxboro and Person County: sunny edges at Mayo Lake Park, the fencerows and old fields fringing Hyco Lake, and any roadside thicket or powerline right-of-way. Farther out in the Piedmont it's everywhere along Falls Lake, the Eno River and Occoneechee Mountain edges, and the margins of Mayo River State Park. Finding it won't be the hard part. The harder job is picking a plant far enough from someone's fence to harvest guilt-free.