Deciduous or evergreen trees or pseudovines (Wightia, not in Australia), sometimes partly a root parasite (Wightia); iridoids present; hairs uniseriate-branched to stellate. Bark with conspicuous lenticels when young, longitudinally splitting with age. Branches opposite. Leaves opposite (whorled in young shoots), petiolate, simple, entire or shallowly 3–5-lobed, margin undulate and often serrate when young; stipules absent. Extrafloral nectaries often present on the leaf blades. Inflorescence a terminal thyrse (Paulownia), or axillary racemes (Wightia). Flowers zygomorphic, bisexual; bracts absent. Calyx campanulate, sepals 5, fused at base, densely covered in stellate hairs. Corolla of 5 fused petals, funnel-shaped, bilabiate, lower lip elongated and 3-lobed; upper lip 2-lobed, with nectar guides on the lip. Stamens 4, didynamous, alternating with petals, filaments free from each other and fused to the corolla tube, twisted near base in Paulownia; anthers tetrasporangiate, dithecal, basifixed, dehiscing by longitudinal slits, thecae positioned head to head or thecae parallel and apically confluent (Wightia); staminodes absent. Nectar disc present, surrounding the ovary. Gynoecium of 2 connate carpels. Ovary superior, 1-locular; style 1, simple, hollow, apical; stigma at most barely expanded or minutely bilobed (Wightia), punctate. Ovules numerous; placentation axile and protruding. Fruit a loculicidal (Paulownia) or septicidal capsule (Wightia), 2-valved or sometimes incompletely 4-valved (Paulownia) with a persistent slightly woody calyx tube. Seeds numerous, linear, membranous-winged; endosperm sparse or? absent.
Paulownia species are extremely fast growing when young. They have been developed in China for reafforestation in recent decades. Paulownia is also sometimes grown for timber. Paulownia tomentosa (Princess Tree) is commonly cultivated in gardens (Rodd 1996, Ellison 1999, Christenhusz et al. 2017, HortFlora 2019), and has become naturalised in Queensland.
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