A deciduous shrub or small tree growing to about 20 ft high in the wild; branchlets densely covered with stellate down. Leaves on adult plants 2 to 41⁄2 in. long, 11⁄2 to 2 in. wide, ovate, heart-shaped to truncate at the base, downy on both sides but usually more so beneath than above, margins deeply double- or triple-too hed, the principal teeth often lobe-like; stalks half to fully as long as the blade. Plants grown from seed go through a juvenile phase in which the leaves are broadly ovate to almost orbicular and deeply lobed, the lobes crenately toothed. Flowers white, 1 to 11⁄2 in. across, borne two to five together in cymose clusters in the leaf-axils of the current season’s growth (sometimes solitary), each flower on a slender drooping stalk 1 to 11⁄4 in. long. Petals overlapping; almost translucent, usually five in number. Anthers purple. Styles ten to fifteen; stigma set obliquely on the style and often adnate to its upper part (decurrent). Carpels ten to fifteen, downy, slightly winged.
Native of the South Island of New Zealand, found in the mountains east of the divide, where the climate is more ‘continental’ than on the rainier west side. This species is discussed below together with its ally H. glabrata. Here it should be pointed out that the latter species was only separated from H. lyallii in 1926, so that references to Hoheria or Plagianthus lyallii in garden and botanical literature before that date refer to one or the other species and more frequently to H. glabrata so far as garden plants are concerned, for that was and still is the commoner species in cultivation.
H. glabrata Sprague & Summerhayes Hoheria lyallii var. β Hook. f.; Plagianthus lyallii Hook. f. in Bot. Mag. under t. 5935; Gaya lyallii T. Kirk and other authors; H. lyallii var. glabrata (S. & S.) E. H. M. Cox – In the Kew Bulletin for 1926, pp. 214-20, Sprague and Summerhayes show that the material originally described as Hoheria lyallii by J. D. Hooker in 1852 actually comprises two species. One is the true H. lyallii, as described above. The other, which they named H. glabrata, differs from H. lyallii in the following characters: stems and leaves glabrous or almost so when mature; margins coarsely toothed but not lobulate and the toothing simpler; apex of leaves usually acuminate and sometimes drawn out into a ‘drip-tip’; stigma capitate or only slightly decurrent; carpels scarcely or not at all winged.
H. glabrata, like H. lyallii, is confined to the South Island of New Zealand but is found west of the divide, where the climate is rainier and somewhat more equable than on the eastern side of the divide, where H. lyallii has its home. It was introduced before 1871 and is figured in Bot. Mag., t. 5935.
Both species are beautiful. Perhaps H. lyallii, with its grey leaves and its more tree-like habit, is the finer species, though it seems to be less common in commerce. H. glabrata is more of a shrub and faster growing, but perhaps softer-wooded and hence more subject to die-back. But a form of H. lyallii distributed in the 1930s under the name H. lyallii var. ribifolia seems to have been tender or at least difficult to cultivate. There is a fine specimen of H. lyallii at Wakehurst Place, Sussex, at the top of the Slips.