Shrub or tree 1–20 m, 10–45 cm dbh. Branchlets four-angled, tomentose. Leaves evergreen, membranous, (4–)8–20(–27) × 3–8(–18) cm, lanceolate to ovate, upper surface largely glabrous, lower surface sparsely to densely tomentose, margins entire, serrate or serrulate, apex acuminate or acute; petiole 1–4 cm long; stipules foliose or reduced to a line along the petiole. Inflorescence paniculate, with two to four orders of branching, 6–30 × 10–20 cm, as long as or longer than average leaves. Flowers fragrant, in clusters of 5–10; calyx campanulate, tomentose outside; corolla yellow to orange, tubular to campanulate, tube 1.5–2.5 mm long. Capsule cylindrical, 0.3–0.5 cm long, glandular, dehiscent; seeds winged. Flowering throughout the year, but primarily July to January, fruiting October to February (Mexico). Norman 2000. Distribution GUATEMALA; MEXICO: Aguascalientes, Chiapas, Chihuahua, Durango, Guanajuato, Guerrero, Hidalgo, Jalisco, México, Michoacán, Morelos, Oaxaca, Puebla, Querétaro, San Luis Potosí, Sinaloa, Tamaulipas, Tlaxcala, Veracruz, Zacatecas. Habitat Occurs in a wide range of habitats, from disturbed areas through desert scrub to pine-oak woodland and cloud forest; between 1000 and 3000 m asl. USDA Hardiness Zone 8–9. Conservation status Not evaluated. Illustration Norman 2000, Stuart 2006; NT178, NT179. Taxonomic note Buddleja cordata subsp. ovandensis (Lundell ex E.M. Norman) E.M. Norman (Mexico: Chiapas) has leaves that appear glabrous underneath; the inflorescence is about half the length of average leaves. Buddleja cordata subsp. tomentella (Standl.) E.M. Norman (Mexico: Coahuila, Nuevo León, San Luis Potosí, Tamaulipas, Zacatecas) is usually a shrub of 1–5 m with white, greenish white or cream flowers.
The balance of persuasion was eventually tipped in favour of the inclusion here of Buddleja by photographs and information supplied by Nick Macer that we were unable to ignore. These showed and told of specimens of B. cordata growing to 25 m with a large bole on the Nevado de Colima, Jalisco, at 2500 m. The decision was sealed by the information that the species has grown outside for 13 years in his own garden in Stroud, Gloucestershire, although it must be said that it has yet to develop any such trunk there. The orange flowers are individually small but are borne in large branched panicles that are quite showy above the dark green leaves. It has been introduced by many different collectors, though is seldom seen in gardens.
There is a good specimen of subsp. tomentella in the Centennial Border at the Hillier Gardens, grown from Sir Harold Hillier’s collection (no. 832) made in 1983. Buddleja cordata is clearly a species to investigate further, and on current evidence, would seem to be hardy in average English Zone 8 conditions.