Rhododendron Cultivars S

'Saint Breward'

Flowers from terminal and upper axillary buds, forming a compact, globular truss. Corolla about 2 in. wide, rotate-funnel-shaped, deep violet-blue. Stamen-filaments pale blue. Stigma pale pink. Leaves softly downy on both sides, mostly elliptic, acute, about 2 in. long. Late April or early May. A dense bush attaining eventually a height of 6 to 8 ft. A hybrid of R. augustinii raised by E. J. P. Magor of Lamellen, Cornwall, and distributed by Maj.-Gen. Harrison. F.C.C. 1962.

Rhododendron 'Saint Breward' in the Valley Gardens, Windsor Great Park, UK. 22 April 2020. Image John Anderson.

Rhododendron 'Saint Breward' at Arboretum Wespelaar, Belgium. 11 April 2024. Image Tom Christian.

Rhododendron 'Saint Breward' at Arboretum Wespelaar, Belgium. 11 April 2024. Image Tom Christian.

'Saint Merryn'

Flowers in trusses of two to four. Corolla widely funnel-shaped, 1 in. wide, deep violet-blue. Stamens coloured like the corolla, with black anthers. Style and stigma crimson. Leaves glossy, about 3⁄4 in. long, obtuse. Late April or early May. A charming hybrid raised by Maj.-Gen. Harrison from ‘Saint Tudy’ × R. impeditum A.M. 1970. ‘Blue Star’ is from the same raiser and of the same parentage.

'Saint Tudy'

‘Saint Tudy’, also raised at Lamellen, is similar to ‘Saint Breward’

Rhododendron 'Saint Tudy' at Exbury, Hampshire, UK. 18 April 2008. Image John Anderson.

Rhododendron 'Saint Tudy' at Exbury, Hampshire, UK. 6 May 2008. Image John Anderson.

'Sang de Gentbrugge'

Rich tangerine-scarlet with a deep orange flare; tube yellow and pink (Ghent; L. van Houtte, 1973).

'Saotome'

Corolla rosy pink (55c), 11⁄4 in. wide, tube 1⁄2 in. long. Anthers maroon-crimson. Style green (Kurume; Wilson No. 21).

'Sapphire'

Flowers about four in the truss. Corolla about 13⁄8 in. wide, pale purplish blue shading to paler at the centre. Calyx-lobes narrowly triangular, acute. Leaves elliptic, obtuse, about 1⁄2 in. long. Of rounded but not very dense habit. April. A hybrid of R. impeditum raised by Frank Knight when he was at the Knap Hill nursery. The pollen came from a sprig of ‘Blue Tit’, given to him as a button-hole when it was first exhibited by Caerhays in 1931 (Journ. R.H.S., Vol. 94, p. 122). ‘Mayfair’, another seedling from the cross, flowers two weeks later, has darker, bluish foliage, and is denser in habit.

'Sappho'

Flowers about 15 in a dome-shaped truss. Corolla widely funnel-shaped, about 3 in. across, centre lobe of lower flowers often duplicated, mauve in the bud, opening white, with a heavy flare of purple overlaid with black. Stamens ten to twelve, with white filaments. Style variable in length, sometimes shorter than the longest stamens, sometimes slightly longer. Medium size, of rather leggy habit. June. (Waterer, Knap Hill, before 1867, but the same name had been used earlier for a hybrid with rosy crimson flowers.) One of the best-known and most likeable of the older hardy hybrids. When the centre lobe is duplicated, as it often is on the lower flowers of the truss, the extra lobe also carries a flare (see W. Watson, Rhododendrons and Azaleas, pl. III). See also ‘Hyperion’.

The distinctive Rhododendron 'Sappho' in the Valley Gardens, Windsor Great Park, UK. 19 May 2017. Image John Anderson.

Rhododendron 'Sappho' in the Valley Gardens, Windsor Great Park, UK. 19 May 2017. Image John Anderson.

Sarita Loder (griersonianum × Loderi)

Flowers about eight in the truss (9 to 11 in the A.M. clone); rachis 3 in. long, brownish; pedicels 13⁄4 in. long, dark brownish red, sticky from stalked white glands. Corolla seven-lobed, widely trumpet-shaped, soft pink shaded paler. Stamen-filaments red. Style glandular, red; stigma dark reddish brown. A tall shrub. Early June or late May. A fine hybrid raised by Lt.-Col. Giles Loder, The High Beeches, Handcross. There are still many plants there, up to 20 ft high, varying greatly in colour. Some have paler flowers than on the plant described here, which grows at Wisley and appears to be similar to the A.M. clone of 1934.

Sarled (sargentianum × trichostomum)

Flowers about seven in the truss. Corolla tubular with a spreading limb, 1⁄2 in. wide at the mouth, tube about 7⁄16 in. long, slightly scaly on the outside of the lobes, shell-pink in the bud, opening almost pure white, but with a slight flush of pale brownish pink in the tube. Leaves 5⁄8 to 3⁄4 in. long, glossy and reticulate. Dwarf, to about 2 ft high, much more in width. Late May. A very free-flowering and vigorous hybrid raised by Collingwood Ingram, The Grange, Benenden, Kent, only now becoming widely available in commerce. The description is based on a plant from the late Miss Davenport-Jones, who distributed this hybrid from the mid-1950s onward. In order to mate the two species ‘I was obliged to go down on all fours and employ a watchmaker’s glass to see what I was doing. I cannot honestly say that the seedlings from this effort have proved any more beautiful than either of their parents, but I can say they are very definitely more vigorous and consequently easier to grow and to propagate’ (C. Ingram, R.C.Y.B. 1967, p. 14).

The form of R. trichostomum used in this cross was previously known as R. ledoides, whence the grex-name Sarled.

'Satan'

Raised at Knap Hill and distributed by Messrs Slocock, is similar to ‘Devon’.

'Scandinavia'

Flowers 14 to 18 in a dome-shaped truss. Corolla open-funnel-shaped, Cardinal Red (near 53b) on a ground of rose-red (58b), with black speckling on the upper lobe. Bushy. Late May or early June. (‘Hugh Koster’ × ‘Betty Wormald’; M. Koster and Sons. A.M.T. 1950.)

'Sekidera'

Corolla 3 in. wide, funnel-shaped, pure white and light purple speckling on the upper lobes. Stamens seven or eight. Calyx-lobes up to 1 in. long, acute; pedicels and edge of calyx-lobes glandular. Low, spreading habit. May. A lovely azalea, not completely hardy. It belongs to the same complex of Japanese garden hybrids as Mucronatum, but is near to R. macrosepalum.

Seta (moupinense × spinuliferum)

Flowers from terminal and upper axillary buds, about seven in all on the plant seen. Corolla tubular-funnel-shaped, 1 1⁄4 to 1 1⁄2 in. long, about 1 in. across, white or pinkish at the base, shading to bright crimson on the lobes. Anthers chocolate-coloured. Style greenish white with a crimson stigma. Leaves lanceolate to elliptic, up to 2 in. long, margins recurved, obtuse to subacute at the apex, rather stiff, midrib beneath pale, yellowish. A small erect shrub to about 5 ft. March or April. (Aberconway. A.M. 1933. F.C.C. 1970.) Quite a pretty hybrid, of unusual appearance, which has been recommended for an Award of Garden Merit.

Rhododendron Seta at Exbury, Hampshire, UK. 20 March 2006. Image John Anderson.

Rhododendron Seta at Exbury, Hampshire, UK. 20 March 2006. Image John Anderson.

Rhododendron Seta in the Savill Garden, Windsor Great Park, UK. 1 March 2022. Image John Anderson.

'Seven Stars'

Flowers 12 to 14 in a lax truss. Corolla funnel-shaped, 2 in. wide, light magenta pink in the bud, opening white, flushed with light pink along the centre of the lobes. Leaves oblanceolate or narrow-obovate, 4 in. or slightly more long. Compact habit, ultimate size unknown. Late April or early May. (R. yakushimanum × Loderi ‘Sir Joseph Hooker’; Crown Estate Commissioners. A.M. 1967.)

Rhododendron 'Seven Stars' at Exbury, Hampshire, UK. 5 May 2010. Image John Anderson.

Rhododendron 'Seven Stars' in the Savill Garden, Windsor Great Park, UK. 5 May 2021. Image John Anderson.

Rhododendron 'Seven Stars' in the Savill Garden, Windsor Great Park, UK. 5 May 2021. Image John Anderson.

Shilsonii (barbatum × thomsonii)

Flowers about 14 in a loose truss. Corolla campanulate, 2 1⁄2 in. wide, of waxy texture, blood-red, with darker coloured nectaries. Stamens white, glabrous or almost so. Style rather thick, glabrous. Calyx petaloid, irregular, up to 3⁄8 in. long. Leaves dark green, 4 1⁄2 by 2 3⁄4 in., apiculate at the apex, cordate at the base. A tall shrub to 15 ft or so. April. The cross was first made by Richard Gill while he was head gardener to Henry Shilson of Tremough, Cornwall, and received an Award of Merit when shown from there in 1900. The Gill cross had the reputation of being hard to grow well, but the cross was remade by Sir Edmund Loder at Leonardslee in Sussex, with better results, and probably in other gardens too. At any rate, what is now grown as ‘Shilsonii’ is a good grower, quite hardy, taking after R. thomsonii in its foliage and the form of its flowers, but the latter are of a purer red than in R. thomsonii. The description is from a plant in Mr Hillier’s collection at Jermyns House near Romsey.

Rhododendron Shilsonii at Sir Harold Hillier Gardens, Hampshire, UK. 23 March 2012. Image John Anderson.

Rhododendron Shilsonii at Exbury, Hampshire, UK. 16 March 2009. Image John Anderson.

Rhododendron Shilsonii at Mount Usher, Wicklow, Ireland. 7 April 2013. The influence of R. thomsonii in this cross is clear to see, but the flowers are a better red. Image John Anderson.

Bark on a mature Rhododendron Shilsonii at Mount Usher, Wicklow, Ireland. 7 April 2013. Image John Anderson.

'Shin-sekai'

Corolla 1 in. wide with a slender tube 1⁄2 in. long, and narrow, spreading lobes, creamy white, tube deeper coloured. Style contorted. Calyx irregularly petaloid. Dwarf and compact (Kurume; Wilson No. 3, but introduced earlier). A.M. 1921; A.M.T. 1952. Hardy.

'Shiromanyo'

(R. mucronatum f. narcissiflorum (Planch.) Wils.), with double white flowers. The two double forms were introduced to cultivation in the last century, and are mentioned by Millais (1917) as being grown out-of-doors in this country, but seem to have dropped out of commerce.

'Sigismund Rucker'

Flowers about 12 in the truss. Corolla funnel-shaped, 21⁄4 in. wide, coloured a strange shade of magenta-crimson (71b), with heavy black spotting. Style purplish red, with a small dark red stigma. Ovary dark brownish green, glabrous. Leaves elliptic. Medium size. (Waterer, Knap Hill.) An old hybrid now rarely seen. It is named after a well-known amateur gardener of the last century (d. 1875), who had a collection of orchids and ferns in his garden at Wandsworth.

'Silver Moon'

Corolla 21⁄2 in. wide, white faintly spotted with yellowish green on the upper lobes, slightly waved at the margins. Compact habit, attaining probably 4 ft or so in height. Early June, A.M.T. 1973. A promising azalea of recent introduction, flowering later than the white Mucronatum and ‘Palestrina’. It is one of the many clones raised at Glenn Dale, USA, from a complex cross: (Mucronatum ‘Lilacinum’ × ‘Willy’) × (‘Mrs Carmichael’ × ‘Willy’).

'Silver Slipper'

Creamy white with a yellow flare; bud, opening flower and its tube tinged with pink; fragrant (Knap Hill-Exbury, distributed by Waterer, Bagshot, 1948). A.M.T. June 7, 1962; F.C.C.T. 1963.

'Sir Charles Lemon'

Flowers about ten per truss; rachis 3⁄4 in. long; pedicels 1⁄2 in. long, clad with short hairs. Corolla campanulate, 21⁄2 in. wide, white, with purplish spotting on the upper lobes, extending into the throat. Stamens sparsely hairy at the base, with brown anthers. Style glabrous. Ovary oblong-conoid, with a few crisped hairs. Calyx obsolete. Leaves oblong-elliptic, to 6 in. long, main veins deeply impressed above, undersurface clad with a vividly coloured rusty-red tomentum, not extending to the midrib, which is prominent, pale green. A large shrub or small tree. April. Although sometimes placed under R. arboreum the almost glabrous ovary shows that it cannot belong to that species. Lionel de Rothschild, who pointed this out, suggested that it is a hybrid between R. arboreum var. cinnamomeum and R. campanulatum, which seems very likely (Y.B. Rhod. Ass. 1934, pp. 108–9). The original plant grew at Carclew in Cornwall, where it was planted in the time of Sir Charles Lemon (d. 1868). Millais, in his first volume (1917), gives the size of the original specimen as 30 ft in height and 27 yds round. Assuming that the same plant is referred to, which seems almost certain, it was 10 ft high in 1874, and grown under the name R. cinnamomeum (Journ. Hort., Vol. 27, n.s., p. 403). It is reputed to have been raised from seeds collected in the Himalaya by Hooker, but even so, that would be no argument agains its hybrid origin, since such hybrids may well occur in the wild.

‘Sir Charles Lemon’, both in foliage and flower, is one of the finest of rhododendrons, though its full beauty is revealed only after it attains a fairly large size.

Rhododendron 'Sir Charles Lemon' in the Valley Gardens, Windsor Great Park, UK. 16 April 2018. This remains a deservedly popular rhododendron in gardens large enough to accommodate it. Image John Anderson.

Rhododendron 'Sir Charles Lemon' in the Valley Gardens, Windsor Great Park, UK. 16 April 2018. Image John Anderson.

Close up on a truss of Rhododendron 'Sir Charles Lemon'. Achamore Garden, Gigha, UK. 29 April 2024. Image Tom Christian.

The leaf undersides on Rhododendron 'Sir Charles Lemon'. Achamore Garden, Gigha, UK. 29 April 2024. Image Tom Christian.

'Sir Edmund'

Blush, veined with pink when first open, mostly six-lobed. The original plant flowered some years after Sir Edmund Loder’s death in 1920. A.M. 1930.

See notes for Loderi group

Sir Frederick Moore (discolor × St Keverne)

Flowers slightly fragrant, about 15 in a large compact truss. Corolla funnel-shaped from a broad base, seven-lobed, 3 to 4 in. wide, slightly frilled at the margin, light pink, with conspicuous speckling of brown or crimson in the upper part of the throat. Style pale green with a large pale red stigma. Leaves up to 7 in. long and 2 in. wide. A large vigorous shrub. Late April or early May. (Rothschild, 1935. A.M. 1937, F.C.C.T. 1972.) A beautiful hybrid with flowers of a clear pink. It is remarkably hardy considering that St. Keverne is a hybrid between R. griffithianum and R. zeylanicum (R. kingianum Hort.). It is named after a former Director of the Glasnevin Botanic Garden.

– ‘Charlotte de Rothschild’, which belongs to this grex, was named recently and received an A.M. in 1958.

Rhododendron Sir Frederick Moore in the Valley Gardens, Windsor Great Park, UK. 5 June 2020. Image John Anderson.

Rhododendron 'Charlotte de Rothschild', another form of the cross, mentioned in the text. Exbury, Hampshire, UK. 23 May 2013. Image John Anderson.

Sir John Ramsden ('Corona' × thomsonii)

Flowers about ten in a dome-shaped truss. Corolla widely funnel-shaped, 3 in. across, red in the bud and stained with that colour on the reverse, inside flushed and veined pink on a creamy white ground. A vigorous, free-flowering shrub to 12 ft or more. May. (Waterer, Bagshot. A.M. 1926. F.C.C.T. 1955.) Named after Sir John Ramsden, Bt, of Bulstrode Park, Bucks. An attractive hybrid, similar to Cornish Cross.

'Sir Joseph Hooker'

White with a slight blush tinge and very faint greenish or greyish markings in the throat, about 12 in the truss. A.M. May 21, 1973. Quite as fine as ‘King George’.

See notes for Loderi group

Rhododendron 'Sir Joseph Hooker', a member of the Loderi Group, at Exbury, Hampshire, UK. 16 May 2013. Image John Anderson.

'Quite as fine as King George' said W.J. Bean of Rhododendron 'Sir Joseph Hooker'. Exbury, Hampshire, UK. 16 May 2013. Image John Anderson.

Sir William Lawrence

This name was given by Lionel de Rothschild, apparently as a grex-name, to hybrids raised by him from R. kaempferi crossed with ‘Hinodegiri’ (the cross which, in Holland, produced ‘Orange Beauty’). What is usually offered by nurserymen as ‘Sir William Lawrence’ has flat-faced flowers of a pale shade of Rose Bengal, becoming whiter and translucent at the centre, quite unspotted, 2 in. or slightly more wide, opening in early June. This azalea cannot be of the parentage given for Sir William Lawrence, but presumably came from Exbury originally. It is possibly a hybrid of R. simsii. The plant that received an Award of Merit in 1958 as ‘Sir William Lawrence’ after trial at Wisley has pink flowers with maroon spotting, produced around mid-May.

Siren (Choremia × griersonianum)

Flowers about ten in a lax truss. Corolla funnel-shaped from a broad base, 21⁄2 in. wide, scarlet, with slight speckling, especially on the three upper lobes. Anthers black. Stigmas red. Calyx coloured like the corolla, irregularly lobed, up to 11⁄2 in. long. Leaves dark green, narrow-oblong, to 61⁄2 in. long, clad beneath with a pale tomentum. Medium size, to about 8 ft. Late April or May. (Aberconway. A.M. 1942.) A fine scarlet rhododendron, with a strikingly large calyx, derived from R. haematodes, one of the parents of Choremia.

Smithii (arboreum × ponticum)

Flowers about 20 in a dense truss, on glandular pedicels. Corolla campanulate, slightly undulated at the edge, rosy purple, almost crimson, heavily speckled, mostly on the upper lobes. Stamens hairy in the lower half. Style glabrous; ovary ‘rusty’. Leaves oblong or elongate, acute, viscid and hairy beneath when young, becoming glabrous.

The above is based on Sweet’s original description, made from a plant that flowered in 1831. The cross had been made both ways by William Smith, who at that time was still gardener to the Earl of Liverpool at Coombe Wood House, Kingston-on-Thames, but later set up his own nursery at Norbiton nearby. Since Altaclerense also first flowered in 1831 it is likely that the two crosses were made at the same time, i.e., in 1826. The Smithii cross was later made in other places, e.g., by Rogers’ Red Lodge Nursery, Southampton; by Rendall of St Austell, Cornwall; by Davis of Hillsborough, Co. Down (who around the middle of the last century was offering layers 12 to 15 in. high at £3 10s a hundred); and no doubt in other gardens.

Smithii is not much planted at the present time and may not even be in commerce. But it has the distinction of growing to a greater size than any other rhododendron in this country. The examples given by Millais in his first volume (1917) were: Leonardslee, Sussex, 80 years planted, 25 ft high and 3 1⁄2 ft in girth at 5 ft; Tregothnan, Cornwall, 30 ft high, 8 ft in girth at ground level, dividing into three stout branches at 3 ft; Carclew, Cornwall, a tree 35 ft high, 5 ft in girth at 4 ft; also a very large specimen at Saltwood in Kent.

Smithii is perfectly hardy and flowers in late April or early May. Having been raised so many times it is variable, according to the forms of the two parents used. And it may be that the ponticum used was not pure, but one of its early hybrids with R. maximum. A. J. Ivens, in his manuscript notes, provided two descriptions, both agreeing very well with Sweet’s except that in one plant (at Embley Park) the ovary is glandular-downy (as it may have been in the type), while in the other (from Rogers’ nursery) it is almost glabrous.

Rhododendron Smithii at Trelissick Garden, Cornwall, UK. 19 March 2011. Image John Anderson.

A fine old plant of Rhododendron Smithii at Trelissick Garden, Cornwall, UK. 19 March 2011. Image John Anderson.

'Smithii Aureum'

Similar to ‘Broughtonii Aureum’ is ‘Smithii Aureum’ (‘Norbitonense Aureum’), which differs in having the leaves very glaucous beneath; its flowers too are of a paler colour and not so flat and open; the flower-stalk is longer and more slender, and the calyx-lobes somewhat narrower. ‘Broughtonii Aureum’ is the better shrub – more beautiful and growing better.

'Snow Lady'

Rhododendron 'Snow Lady' (Castle Howard Arboretum, UK, March 2026). Image John Grimshaw.

Snow Queen ('White Pearl' ('Halopeanum') × Loderi)

Flowers fragrant, 12 to 15 in a conical truss; rachis and pedicels reddish. Corolla funnel-shaped, 3 3⁄4 to 4 in. wide, five-lobed, flushed with pink in the bud, opening pure white with a small red mark and a few speckles in the throat. Leaves dark dull green, 8 by 2 1⁄2 in. Tall and vigorous. May. This fine hybrid was raised at Leonardslee in Sir Edmund Loder’s time and put into commerce by the Knap Hill Nursery, who got their stock from J. G. Millais. It is very much in the style of Loderi, but easier to grow successfully. Millais gave the name ‘Snow Queen’ to one particular plant, which he thought to be distinct from other plants from the cross, so the name is strictly clonal only, not a grex-name as stated in the International Register. Millais, incidentally, gives the parentage as ‘Gauntlettii’ × Loderi. See ‘White Pearl’ and ‘Gauntlettii’.

Rhododendron Snow Queen at Exbury, Hampshire, UK. 12 May 2014. Image John Anderson.

Rhododendron Snow Queen in the Savill Garden, Windsor Great Park, UK. 29 April 2020. Image John Anderson.

'Snowflake'

Flowers in a conical truss. Corolla widely funnel-shaped, 3 in. across, with rounded lobes, white with a flare of brownish-green speckles, and with a red mark at either side at the base of the two upper sinuses. Anthers large, pale pink. Style white, expanded into a large stigma. Leaves elliptic, acute, 51⁄2 by 2 in. Medium size. June. (Waterer, Knap Hill, before 1875.)

'Soleil d'Austerlitz' ('Sun of Austerlitz')

Flowers up to 30 in a dense truss; pedicels only 1⁄2 in. long, gladular. Corolla broad-campanulate, 21⁄4 in. wide, crimson shading to paler in the tube, slightly spotted at the base of the centre lobe. Style stout, glabrous. Ovary white felted. Leaves silvery beneath, recalling those of R. arboreum. A dense, compact shrub, broader than high. April or early May. This hybrid is usually called ‘Sun of Austerlitz’, but John Waterer had it in 1852 under its French name; also ‘Charles Truffaut’, which is known to have been raised by Bertin at Versailles, before 1851. It is a hybrid of R. arboreum.

'Songbird'

Inflorescences from terminal and axillary buds, forming bunches of as many as 20 flowers at the ends of the shoots. Corolla rotate, 11⁄8 in. wide, hairy in the throat, deep violet-blue. Stamen-filaments densely hairy at the base. Calyx well developed, with lobes up to 1⁄4 in. long, densely ciliate. Leaves glossy, elliptic, obtuse, about 3⁄4 in. long. April. An excellent dwarf shrub, raised by the late Sir James Horlick, Bt, from ‘Blue Tit’ crossed with R. russatum, whose influence shows in the deep colouring of the flowers, the large calyx, and the hairy middle of the corollas, to which both the stamens and the corolla itself contribute. A.M. 1957.

'Southamptonia'

Syn. of ‘Russellianum Southamptonia’

A clone of Russellianum still in commerce is ‘Southamptonia’, distributed by Rodgers’ Red Lodge Nursery and probably raised there. This agrees well with the original Russellianum except that the flowers are Tyrian Rose with a lighter centre, slightly speckled. The flowers are in trusses of about seventeen and open in April or early May.

'Southern Cross'

Flowers fragrant, about ten in a compact truss. Corolla widely funnel-shaped, 41⁄2 in. across, wavy at the margin, white with a pink flush deepest on the upper lobes, and with throat-markings of yellowish brown. Leaves dull dark green, 8 by 21⁄2 in. Strong-growing. June. A hybrid between R. discolor and ‘Lodauric Iceberg’, raised by A. F. George and distributed by Hydon Nurseries. It was highly commended after trial at Wisley. Other clones of the same parentage are ‘Gipsy Moth’, ‘Northern Star’, ‘Star-cross’, and ‘Veldstar’.

'Souvenir de Dr S. Endtz'

Flowers about 16 in a dome-shaped truss. Corolla widely funnel-shaped, up to almost 4 in. across, deep rosy pink in the bud, opening pink, shading to paler in the centre, speckled with crimson and brownish crimson on the upper lobes, nectaries crimson. May. (‘John Walter’ × ‘Pink Pearl’; L.J. Endtz and Co. A.M. 1924. F.C.C.T. 1970.) One of the best of the derivatives of ‘Pink Pearl’, with flowers of a purer and richer pink and differing also in the dome-shaped truss and the presence of coloured nectaries in the corolla. It is also of more compact habit.

Rhododendron 'Souvenir de Dr S. Endtz' at the National Botanic Gardens Glasnevin, Dublin, Ireland. 10 May 2009. Image John Anderson.

Close-up on a truss of Rhododendron 'Souvenir de Dr S. Endtz' at the National Botanic Gardens Glasnevin, Dublin, Ireland. 27 May 2013. Image John Anderson.

'Souvenir of Anthony Waterer'

This hybrid, raised at Knap Hill, is in commerce and described as having salmon-pink flowers with an orange flare.

'Souvenir of W. C. Slocock'

Flowers about 12 in a compact truss. Corolla funnel-campanulate, 3 in. wide, buff-pink in the tight bud, expanding bud and corolla when first open cream-coloured flushed with pink, becoming ivory with a pink flush, with crimson speckling on a paler ground. Compact habit. May (campylocarpum hybrid; Slocock, before 1928.)

Rhododendron 'Souvenir of W. C. Slocock'. Achamore Garden, Gigha, UK. 29 April 2024. Image Tom Christian.

Rhododendron 'Souvenir of W. C. Slocock'. Achamore Garden, Gigha, UK. 29 April 2024. Image Tom Christian.

'Spek's Brilliant'

Bright orange-scarlet with a deeper flare (Mollis; Jan Spek). The true variety is a clone, but seedlings are sometimes sold under the name.

'Spek's Orange'

Bright orange with a greenish flare (Mollis; Jan Spek). F.C.C.T. May 26, 1953. As suggested by the date of the award, this clone is late-flowering for a Mollis azalea.

Spinulosum (racemosum × spinuliferum)

This hybrid was first made at Kew, later at Bodnant and twice at Exbury, the second time using Forrest’s dwarf form of R. racemosum. The flowers are borne in terminal and axillary inflorescences, as in R. racemosum, but the corollas are more tubular, with protruding stamens, and the leaves are larger than in that species. The dwarf Exbury form is considered to be the best. In this the corollas come near to R. spinuliferum in their colouring and the leaves are up to 3 in. long, dark green above. A.M. 1948. In the form that received the same award when shown from Wisley in 1944 the flowers are white shading to pink at the tips of the lobes. This probably represents the Kew cross.

'Splendens'

Corolla 1 to 11⁄2 in. wide, funnel-shaped with a narrow tube, deep rosy pink with a redder centre. Calyx normal. Low, spreading habit. Late May or early June. A hybrid between ‘Amoenum’ and some form of R. indicum, free-flowering and quite pretty. Something very like it is in commerce under the incorrect name ‘Caldwellii’. The type ‘Caldwellii’ had hose-in-hose flowers.

'Stanley Davies'

Flowers about 16 in a compact truss, on whitish-green pedicels. Corolla wide-campanulate, 21⁄2 in. wide, dark glowing red but with a slight blue tinge when seen in diffused light, paling to almost white at the base of the throat and with black markings mostly confined to the centre lobe. Stamens densely hairy towards the base, with bluish-purple anthers. Leaves lanceolate to oblong-obovate, 5 by 2 in. Medium size, bushy. Late May or early June. This hybrid was distributed by Messrs Clibrans of Altrincham, who exhibited it at an R.H.S. Show in 1912, but was probably raised by Isaac Davies of Ormskirk, who certainly bred hardy hybrids, though he is best known for his lepidote hybrids, such as Praecox. It is still available in commerce, and was used by the Dutch breeders, its most famous offspring being ‘Britannia’.

Stanleyanum (arboreum album × campanulatum)

R. stanleyanum appears to be the first name of specific form given to a known hybrid between R. arboreum and R. campanulatum. This was raised by the nurseryman Whalley, of Fairfield Nurseries, Liverpool, and is described in Gard. Chron. (1851), p. 197. The description is sufficient to show how different this hybrid was from ‘Boddaertianum’, which is supposed, almost certainly wrongly, to be R. arboreum × R. campanulatum. Another known hybrid between these two species is ‘Comtesse Ferdinand Visart’, raised by Van Houtte from R. arboreum var. cinnamomeum, and figured in Fl. des Serres, Vol. 9, t. 935. See also ‘Sir Charles Lemon’.

'Starfish'

Flowers about nine in a conical truss. Corolla flat, almost 4 in. across, edges of lobes undulated and recurved, soft pink shading to white at the centre, with markings of crimson and brown. Late May. (Waterer, Bagshot, before 1922.) A curious rhododendron with star-shaped flowers, said to be a seedling of ‘Mrs E. C. Stirling’.

'Stewartstonian'

Corolla 11⁄2 in. wide, deep brownish red (47a), slightly darker in the throat. Stamen-filaments and style red, the latter long-exserted. Leaves glossy, the upper ones obovate to almost rounded, bronze in winter. May. Rather like ‘Addy Wery’. Raised by J. B. Gable, Stewartstown, USA, whence the name, which is often wrongly given as “Stewartsoniana”.

'Strategist'

Flowers about 15 in the truss. Corolla funnel-shaped, 2 to 23⁄8 in. wide, with broad lobes, rosy pink, paling at the centre, with light speckling of crimson and olive-green on the centre lobe. Anthers mauve, filaments white. Style dull crimson. Leaves broadly oblong-elliptic, 5 by 17⁄8 in., rounded at the base. Tall-growing. June. (Waterer, Bagshot.)

'Strawberry Ice'

Light flesh-pink, veined and flushed with deeper pink; flare yellow; truss with twenty or more flowers (Knap Hill-Exbury, distributed by Waterer, Bagshot). A.M.T. May 31, 1962. Recommended for an Award of Garden Merit.

'Streatley'

Flowers about nine in a lax truss. Corolla widely campanulate, 2 in. wide, deep rosy pink in the bud, opening white flushed with pink, lightly speckled with red. Leaves dark green, elliptic, somewhat convex above, with an impressed midrib. Dwarf habit (aberconwayi × yakushimanum; Crown Estate Commissioners). A.M. May 5, 1964. An interesting hybrid, not unlike R. yakushimanum in foliage, but with differently shaped flowers. Another seedling from this cross, so far unnamed, is taller, with broader leaves.

Rhododendron 'Streatley' in propagation at the Savill Garden, Windsor Great Park, UK. 8 April 2024. Image John Anderson.

'Suga-no-ito'

Corolla 11⁄2 to 13⁄4 in. wide, soft shell-pink, paler in the throat with six pale reddish-brown speckles on the upper lobes. Calyx-lobes elongate and partly petaloid (Kurume; Wilson No. 31). Hardy. According to Lee (The Azalea Book, p. 139), the correct name for this azalea is ‘Kumo-no-ito’.

'Sun Chariot'

Golden yellow with a flare of deeper yellow (Knap Hill-Exbury, distributed by Waterer, Bagshot). F.C.C.T. May 31, 1967. One of the finest yellows in the Knap Hill group, flowering in late May or early June.

'Sunbeam'

Chinese yellow flushed apricot, with a tangerine blotch (M. Koster and Sons, 1895). A.M.T. May 16, 1962. A hybrid of the yellow ‘Altaclarense’, usually classed as a Mollis.

'Superba'

Buff-pink in the bud, opening white flushed with pink, becoming pure white, margins frilled; flare yellow, large, occupying most of the central lobe (Occidentale Hybrid; M. Koster and Sons, 1901).

'Susan'

Flowers about 12 in the truss; pedicels almost glabrous. Corolla funnel-shaped, 3 to 31⁄2 in. wide, five-lobed, Amethyst Violet (81d), the three upper lobes somewhat darker than the two lower, heavily speckled with maroon. Leaves dark green, elliptic, thinly felted beneath when young, later greenish brown there, 51⁄2 by 21⁄2 in. A large shrub of compact habit, vigorous. May. This hybrid is as fine in foliage as it is in its flowers, which are near to blue in some lights. It is a pity that there are not six hybrids as good, flowering at fortnightly intervals from the beginning of May. It is perfectly hardy, but needs slight shade. Unfortunately, its history is not fully known. It was raised by P. D. Williams of Lanarth, Cornwall, and originally known as ‘Williams’ Campanulatum Hybrid’, but later named ‘Susan’ and put into commerce by Messrs W. C. Slocock. It received an Award of Merit in 1948 and an F.C.C. in 1954, both after trial (the A.M. of 1930 belongs to a quite different hybrid, raised at Nymans and also called ‘Susan’). It is near to R. campanulatum, but it is difficult to believe that it is a hybrid between that species and R. fortunei, as stated by Lionel de Rothschild, and later in the International Register.

Sussex Bonfire (Cornish Cross × haematodes)

Truss six- to eight-flowered. Corolla campanulate with a spreading limb, 21⁄2 in. wide, dark blood-red, with dark nectaries. Calyx petaloid, to 3⁄4 in. long, coloured like the corolla. Leaves dark green, more or less elliptic, glabrous, to 4 by 2 in. Medium size. Late April or early May. (Loder. A.M. 1934.) The description is made from a commercial plant, of little merit, as the flowers are too dark and rather lustreless. In the Borde Hill form of the cross, the flowers are a lighter and brighter red, and the leaves lighter green. But such variation is only to be expected when such a variable hybrid as Cornish Cross is used as a parent.

'Swansong'

Another white of the same parentage as ‘Silver Moon’, also late-flowering but of lower more spreading habit, is ‘Swansong’, A.M.T. 1972.

'Sweet Simplicity'

Truss rounded, with 18 to 20 flowers. Corolla funnel-shaped, 21⁄2 to 23⁄4 in. wide, white edged with delicate pink, with olive-green markings on the upper lobes. Anthers pale yellow. Ovary reddish green, glandular and downy. Leaves 61⁄2 by 21⁄2 in., dark green and fairly glossy. Medium size. Compact habit. June. (Waterer, Bagshot, before 1922. A.M.T. 1970.) A charming hybrid, not unlike ‘Lady Clementine Mitford’, but whiter in the centre, and with less conspicuous markings.

'Sylphides'

Pale pink with a flare of buttercup-yellow (Knap Hill). A.M.T. 1957.