A large evergreen shrub 8 to 12, or sometimes up to 25 ft, high, spreading half as much more in diameter; young wood glabrous. Leaves oblong-oblanceolate or oblong-elliptic, 3 to 7 in. long, 1 to 21⁄4 in. wide; pointed, tapering at the base, finely toothed to the base, glabrous, and dark glossy green, of firm leathery texture. Flowers produced during May in a cluster of panicles, terminating the shoots of the previous year, and from 4 to 6 in. long and wide. Corolla pendent, white, pitcher-shaped, 1⁄4 to 5⁄16 in. long, contracted at the mouth, where are five shallow, rounded teeth; calyx-lobes 1⁄8 in. long, green, narrowly ovate; flower-stalk 1⁄4 in. or less long, with a pair of bracts. Bot. Mag., t. 8283.
P. formosa is a wide-ranging species, from Nepal through the eastern Himalaya, Assam, upper Burma to south-west and parts of central China at 6,000 to 11,000 ft; the date of introduction is not known, but it was cultivated at Lamorran in Cornwall in 1881. This shrub is perfectly hardy and reaches a large size in the woodland gardens of southern England, though the finest specimens are to be found in Cornwall, where it attains a height of 25 ft. As in P. japonica and P. taiwanensis, the panicles are produced in autumn, and it has been suggested that when they drop prematurely the cause is dryness at the root rather than frost.
In China, P. formosa appears to be more variable than in the Himalaya, which is the source of all the older plants. In addition to the forms represented in cultivation, and discussed below, there are some with remarkably small leaves, suggesting P. japonica rather than P. formosa – indeed two specimens collected by Forrest in Yunnan during his first journey were originally identified as that species.
P. formosa received a First Class Certificate when shown from Caerhays on April 29, 1969.
At Wakehurst Place in Sussex there is a plant of typical P. formosa raised from Forrest 8945, collected in Yunnan on the Shweli-Salween divide in 1912 at 9,000-10,000 ft. It has made a dense many-stemmed bush about 15 ft high, with leathery, rather stiff, slightly undulated leaves very rugulose above, elliptic to broadly so or slightly ovate, relatively rather broad for the species, 23⁄4 to 31⁄2 in. long, 11⁄8 to 15⁄8 in. wide, dull brownish red when young; in Forrest’s original material under this number the leaves are similar, though rather smaller. The flowers are produced in large panicles about once every three years; corolla about 5⁄16 in. long; calyx pale green. There is a matching plant at Borde Hill which was planted before 1935 as Pieris species F.8945, and is believed to have come from Messrs Marchant. Flowering material from the Wakehurst plant was exhibited by Sir Henry Price on March 20, 1957, and received an Award of Merit. Unfortunately the award was given to it under the cultivar-name ‘Wakehurst’, which traditionally belongs to a clone of P. formosa var. forrestii (see below). The application of the same cultivar-name to two quite different plants has been the source of much confusion and should be rectified. The plant discussed here is inferior to the true ‘Wakehurst’, and slow-growing and tender when young.
A late-flowering form of P. formosa was exhibited by Mrs Warren, The Hyde, Handcross, Sussex, on June 23, 1964, under number Forrest 29002. The flowers are about the normal size for the species but the leaves are unusually narrow, 25⁄8 to 31⁄4 in. long, 5⁄8 to 1 in. wide. There are plants at Borde Hill, Sussex, of unknown provenance, with the same narrow leaves and also late-flowering. The young foliage is bronzy, and the flowers are borne in stiffly branched panicles; calyx white, sometimes tipped with green. They are very hardy and flower every year.
var. forrestii (Harrow) Airy Shaw P. forrestii Harrow; Gaultheria forrestii Hort., not Diels – This variety was described in 1914, as a species, from a plant raised from seeds collected by Forrest. There is no specimen from the original wild plant, but according to Forrest the seeds came from the Tali range in Yunnan. There can be little doubt that they were collected during his first expedition for A. K. Bulley (1904-6), not the second (1910). In 1914 the only plants in cultivation were those growing in the Royal Botanic Garden at Edinburgh and in the nurseries of Messrs Bees (of which firm Mr Bulley was the founder and proprietor). The description was made from a plant at Edinburgh, then some 3 ft high, and was probably drawn up by W. W. Smith, though the name is attributed to R. L. Harrow, who was Principal Gardener there at the time. In the original description it was said that P. forrestii was very near to P. formosa, differing in a number of minor points, ‘the sum of which is beyond mere varietal divergence’. These were, notably, the more pendent habit, the slenderer pedicels with more narrow bracts, the whitish sepals, the rounder, longer corolla, more constricted at the mouth, which had ‘straight-cut pentagonal edges’ and shorter, more erect lobes; and the longer and slenderer style. No mention was made of the colour of the young foliage.
A different view of P. forrestii was taken by the Kew botanist H. K. Airy Shaw, in an article accompanying the plate in the Botanical Magazine, t. 9371. He wrote: ‘Examination of the ample … material of P. formosa and P. Forrestii in the Kew Herbarium shows that the latter constitutes what may be termed the “grandiflora” end of a long series, between the members of which no hard and fast lines can be drawn. Although it is possible that a monographer might feel inclined to sweep the subject of our plate into the oblivion of total synonymy, the middle course of according it varietal rank has been adopted, as being possibly the best compromise between scientific conscientiousness and horticultural expediency.’
P. formosa var. forrestii is represented in commerce mainly by the following clone, which should not be confused with the plant which received an Award of Merit in 1957 under the name ‘Wakehurst’ (see above):
cv. ‘Wakehurst’. – A shrub up to 18 ft high. Leaves oblong-elliptic to oblanceolate, apex acute or acuminate, sharply pointed, base cuneate to narrowly rounded, margins serrated, brilliant red when unfolding in March or April, fading to crimson pink, then almost colourless for a while before turning chlorotic green and eventually the normal deep green. Flowers in large trusses, profusely borne in some years; calyx white; corolla broad-urceolate, about 3⁄8 in. long. It is hardy and vigorous, but the young growths may be killed by spring frost.
‘Wakehurst’ received a First Class Certificate on May 20, 1930, as P. forrestii, when exhibited by Gerald Loder of Wakehurst Place, Sussex. There are still several plants in the garden, and larger ones at Nymans and Borde Hill in the same county, both known to have come from Wakehurst. The history of this clone is not known. According to previous editions of this work, the Wakehurst plant was raised from F.8945, but it differs so much from Forrest’s original specimen, and from plants known to have been raised from this batch of seed, as to suggest that Loder inadvertently misinformed the author about its origin. But for this statement it would never have been doubted that ‘Wakehurst’ derived from the original introduction of var. forrestii. It certainly bears a strong resemblance to the type, i.e., the plant to which the name P. forrestii was originally given.
Six years before the Wakehurst plant received the First Class Certificate, A. K. Bulley exhibited the var. forrestii at the Chelsea Show, when it was given an Award of Merit (May 27, 1924, as P. forrestii). The foliage was said to be salmon-pink – the colour ‘Wakehurst’ would have at that season. There is at the present time a large plant of the var. forrestii in what was once Mr Bulley’s garden, now the Botanic Gardens of the University of Liverpool, at Ness in Cheshire, which has young foliage of a brilliant red. Mr J. K. Hulme, the Director, tells us that one of the old gardeners there remembers having helped to move this plant to its present position in 1919, when it was already a good size. This plant bears a strong resemblance to ‘Wakehurst’; so too does the material figured in the Botanical Magazine, the source of which was a plant at Headfort, raised from a cutting received from Edinburgh in 1920. That the Ness plant is an original from Forrest’s seeds is almost beyond doubt, and it is very likely, though perhaps unprovable now, that the original commercial stock sold as P. forrestii, including the Wakehurst plant, derives from this.
The form of Forrest’s variety that most impressed the collector himself was found by him in April 1925. The note attached to his flowering specimens (F.26518) reads: ‘In every sense a most exceptional species. Habit good, foliage and flowers most attractive, the latter finer than anything I have yet seen of this class, large and purely coloured and produced most freely. A finer thing than even the type.’ He found it on the Burma-Yunnan frontier on the western flank of the Nmai Hka-Salween divide at 10,000 ft, as a shrub 5 to 6 ft high. He introduced it the same autumn (F.27401, which is the duplicate in fruit of F.26518).
In cultivation, this introduction has proved to be very unlike the var .forrestii as generally known. The flowers are of a remarkable size, sometimes not much less than 1⁄2 in. long, borne in stiff, upright panicles, and the young foliage is bright green. Material of F.26518 in the Kew Herbarium is from Borde Hill in Sussex and from Fota, Co. Cork, Eire. There is a similar specimen from Trewithen, Cornwall, without number. Plants at Caerhays in the same county, one now 20 ft high, were raised from seed under F.27765 and F.27165, but these numbers are wrong, the first belonging to a Vaccinium species and the latter to a Camellia species. The clone ‘Charles Michael’ derives from the Caerhays plant under F.27765, and is available in commerce. The panicles are upright, about 8 in. long, 4 in. wide, and the corollas 1⁄2 in. long. The young growths are bronze-coloured. A.M. 1965.
P. ‘Forest Flame’. – Leaves oblanceolate or oblong-oblanceolate, acute at the apex, narrowly tapered to the base, up to 5 in. long by 1 in. wide, margins with close, shallow serrations. This clone arose at the Sunningdale Nurseries as a self-sown seedling at the foot of a plant of P. japonica. It is near to this species in the shape and toothing of its leaves, but their colouring when young and their size, as well as the vigour of the plant, suggests that P. formosa var. forrestii, or possibly P. formosa F.8945, was the other parent. It comes into growth somewhat earlier than ‘Wakehurst’. The foliage is not quite so vivid when young, but is more elegant, and the habit of young plants is more compact and symmetrical. Award of Merit May 1, 1973. Similar to this, and also a hybrid, is ‘Firecrest’, put into commerce by Messrs Waterer, Sons and Crisp. It was originally distributed as ‘Pieris species F.8945’, and presumably a plant under that number was the seed-parent. The other parent was probably P. japonica. ‘Firecrest’ received an Award of Merit on May 1, 1973.