Gaultheria × wisleyensis Marchant ex D.J.Middleton

[Text from Bean’s entry ×Gaulnettya wisleyensis, rearranged July 2023]

A bushy evergreen shrub 3 ft or more high, spreading by suckers. Leaves mostly elliptic or elliptic-oblong and 1 to 11⁄2 in. long (somewhat longer on sterile shoots), pointed at the apex, wedge-shaped or rounded at the base, of firm, leathery texture, almost glabrous, medium green above, paler beneath, strongly net-veined on both surfaces. Flowers pearl-white, borne in downy, glandular clusters of terminal and axillary racemes near the end of the shoots, each 11⁄2 to 21⁄2 in. long, carrying six to fifteen flowers and opening in May and June. Fruits dark purplish red, fleshy, oblate-globose, about 1⁄4 in. across, clasped at the base by the enlarged fleshy calyx.

The hybrid described above was noticed in 1929 in the garden of the Royal Horticultural Society at Wisley, where it grew on a mound in the Wild Garden in the company of other ericaceous plants, including Gaultheria shallon and [what was then known as] Pernettya mucronata [now Gaultheria mucronata]. There can be little doubt that it is a hybrid between these two species, showing the influence of the former in its net-veined foliage and in the enlarged fleshy calyx seen at the base of the fruits; and of the pernettya parent in its inflorescence and fleshy fruits. For an illustrated note on this hybrid by B. O. Mulligan see Journ. R.H.S., Vol. 64 (1939), pp. 125–127.

This shrub, now common in cultivation, makes a neat evergreen and is attractive in flower and fruit. It was given an Award of Merit at Vincent Square on 20 June 1939. It is propagated by half-ripe cuttings or by division.

The name ‘Wisley Pearl’, published by Mr Mulligan in the note referred to above, should be regarded as a clonal name for the descendants by vegetative propagation of the original plant.

[Gaultheria and Pernettya were formerly regarded as distinct genera based on the capsules being dehiscent in the former and fleshy in the latter, but all are now treated as Gaultheria. The nothogenus ×Gaulnettya Marchant was used for hybrids between the two groups. JMG 2023] [Bean’s text continues:] The plant described here – ‘Wisley Pearl’ – arose in cultivation and is of interest in that it unites a Californian species of Gaultheria with a very dissimilar species of Pernettya from South America. Hybrids between the two genera also occur in the wild. Dr Philipson records (Philipson and Hearn, Rock Garden Plants of the Southern Alps, p. 80) how he discovered a colony of such hybrids in the Southern Alps of New Zealand: ‘I paused to look at one plant [of Gaultheria depressa] that seemed different and saw that its berries instead of being spherical were all shaped like five-pointed stars. Between the spreading fleshy rays was set a globular centre-piece. The whole looked like a flower fashioned in wax, and its beauty was heightened by the delicate shell pink flush that deepened on the broad points of the star.’ The other parent of this gaulnettya was Pernettya nana. Among the other crosses recorded in New Zealand are G. depressa × P. macrostigma and G. antipoda × P. macrostigma. Gaulnettyas have also been found in Central and South America.

It should be noted that the correct name for this hybrid genus is × Gaulnettya Marchant (Choice Trees, Shrubs, 1937). The name was there published with a statement of the parent genera and that is sufficient under the rules of botanical nomenclature (Code, 1966, Art. 40); it has priority over Gaulthettia Camp (1939). But the name × G. wisleyensis has never been validated by a Latin description.