Tree to 40 m, 1 m dbh. Branchlets stout and blackish brown, densely covered with long curly or undulate dark brown or rufous hairs. Leaves evergreen, often in clusters of four to five at branch tips, thin and leathery, 23–40 × 9.4–17 cm, obovate, upper surface dark green and glabrous, lower surface pale green with scattered dark brown curly or undulate hairs, 20–22 veins on each side of the midrib, margins entire, apex acute to short-acuminate; petiole 1.5–3.7 cm long and densely pubescent; stipules adnate to the base of the petiole and densely pubescent. Flowers large and terminal, pale green to white and fragrant; tepals 9–12, the outer three obovate to oblong, 4.5–5 × 2.5 cm, the inner tepals narrower; stamens purplish red; gynoecium sessile with 57–65 carpels. Fruits 6.5–11 cm long, purplish red and globose to ovoid or oblong; ripe carpels, 2.5–3 cm long with a sharp beak, dehiscing along both the dorsal and ventral sutures. Flowering April to June, fruiting September to October (China). Diploid 2n = 38 (Chen & Nooteboom 1993; Liu et al. 2004).
Distribution China W Guangxi, SE Yunnan Laos Vietnam
Habitat Evergreen broadleaved forest, 800–1500 m.
USDA Hardiness Zone 9-10
RHS Hardiness Rating H3
Conservation status Least concern (LC)
The glory of Magnolia dandyi (often referred to under its highly appropriate synonym M. megaphylla) surely lies in the sumptuous russet pubescence of its shoots and on the underside of its huge leaves, velvety to the touch. It rather resembles an evergreen version of M. tripetala (Figlar 2005), although it belongs to a different section. However, this potentially huge tree of warm-temperate forest is only recently introduced, and pushes at the absolute limits of what might be growable in our area.
No rarity in the wild, its light, straight-grained timber is used in construction and plywood maufacture, and it is planted as an ornamental in southern China (Chen & Nooteboom 1993; Xia, Liu & Nooteboom 2008). Gagnepain’s specific epithet honours 20th century British botanist James Dandy, a specialist in Magnoliaceae as well as pondweeds (Potamogeton).
Sean Hogan (2008) suggests (perhaps tongue-in-cheek) using it as a herbaceous plant, for the vigorous new shoots and huge new leaves that a coppiced stump will produce. When not so treated it can form a dense-crowned tree, although conditions need to be perfect for this to occur. Despite their size the leaves are rather thin, and scorch very easily, as seen at Quarryhill, CA, where it was planted on an open hillside (the plant is now lost). Critical requirements seem to be high humidity and constant moisture, together with some shelter from both sun and wind, at least when young – all pointing to this being a plant accustomed to spending its juvenile years in forest understorey. Frost-sensitivity seems to depend on location, with summer heat being implicated in assisting winter-hardiness. –12 °C has killed specimens in both North Carolina and British Columbia (Hogan 2008). Outside our area, a small tree in the Atlanta Botanic Garden, GA was not damaged by –10 to –11 °C in 2003, although even this declined and is now gone; the species is still recorded at the Huntington Botanical Gardens, Los Angeles (Quarryhill Botanical Garden 2021).
In Britain, three plants are growing at Tregrehan, Cornwall. The tallest has reached 3 m, but they have not yet been tested by a cold winter (T. Hudson pers. comm. 2022).
M. dandyi should clearly not be risked in areas where it would normally experience anything more than light frost. No trees are known to have flowered in cultivation yet, but as the flowers are comparatively small and held high in the canopy of mature trees this is of little consequence: simply growing the thing would be enough!