A deciduous shrub of lax habit, 3 to 4 ft high, making coarse, erect, reddish growths, but little branched, silky, half covered with the large silvery stipules. Leaves pinnate, 2 to 4 in. long; leaflets five to nine, shortly stalked, oblong, 3⁄4 to 11⁄2 in. long, 1⁄4 to 5⁄8 in. wide, increasing in size towards the end of the leaf, with broad angular teeth, dark green and glabrous above, grey-woolly beneath. Flowers rosy-tinted white, produced in June and July at the summit of a long-stalked corymb 4 to 6 in. high, each of the three to seven flowers 11⁄2 in. across; petals obovate; calyx-lobes lanceolate, and as long as the petals, the five bracts smaller, linear, and about half as long, very downy.
Native of W. Siberia, Central Asia, Mongolia, N.W. China, Tibet, and the Himalaya; introduced in 1823. This species is very distinct from the other shrubby species in cultivation in its larger, more numerous, toothed leaflets, and in its coarser growths, which are hollow and die back considerably in winter. It belongs to the subgenus Comarum, which is treated as a separate genus by some botanists, on the ground that the receptacle becomes spongy in the fruiting stage, instead of remaining dry as is normally the case in Potentilla. The marsh cinquefoil (P. palustris), which is widespread in the northern hemisphere (including Britain), also belongs to this group.
With regard to its cultivation, Farrer wrote: ‘… it has been at Ingleborough these ten years, and has there in the fat, comfortable place assigned to it once produced (I think) one flower. But from what Purdom tells me I learn that P. Salesoviana requires quite other treatment, and requites it. For it is a plant confined to river shingles and suchlike barren, hungry places: there, as Purdom saw it, the bloom is free, and its effect of remarkable beauty. Let all those, then, who have P. Salesoviana immediately learn its true character by putting it on hunger-strike’ (Gard. Chron., Vol. 59 (1916), p. 100). Purdom saw it during his expedition to Kansu with Farrer, when he went off on his own to the Kokonor.
The clones described below are those most widely available in commerce at the present time (1974). Some of these are of garden origin; others derive from seeds sent home by collectors from western China. In catalogues it is usual to list all the clones under P. fruticosa and this is not wholly incorrect, since the allied species recognised here – P. arbuscula, P. davurica, and P. parvifolia – have been treated as varieties of P. fruticosa by some botanists. But it should be remarked that none of the clones described below belongs to P. fruticosa in the narrow sense, with the possible exception of ‘Jackman’s Variety’ and ‘Gold-finger’.
The shrubby potentillas are among the most valuable of small shrubs, growing well in any moderately fertile soil and flowering over a period of many months. The start and duration of the display depends on the season and to some extent on the variety. Those that are of bushy habit – as most are, with the notable exception of ‘Vilmoriniana’ – make excellent weed-smotherers, and some of the larger sorts could be used to make a dwarf hedge.
Not so long ago it could have been said that the shrubby potentillas are free of serious pests and diseases, but in recent years some have suffered from a disorder that causes the petals to wither in the bud. ‘Elizabeth’ seems to be the worst sufferer. It is thought that Red Spider mite may be the cause of this trouble, and in view of this possibility it would be as well to cut affected plants heavily in early spring and later to spray them with some modern insecticide known to be effective against this pest, e.g., malathion. ‘Elizabeth’ is also subject to mildew.
Flowering as they do on the young shoots, the shrubby potentillas may be pruned quite hard in early spring, but such treatment delays the first flush of flowers and is certainly not necessary. It is more important to cut out old stems periodically to make room for new growth from the base.
The usual method of propagation is by soft-wooded cuttings, which are best taken in early summer. Cuttings of harder wood will also root, but the plants do not develop so quickly.
‘Beesii’ (‘Nana Argentea’). – Flowers buttercup-yellow, about 3⁄4 in. wide, in few-flowered cymes, producing stamens only. Leaves with three or five leaflets, the lateral ones elliptic, about 7⁄16 in. long, silvery above from the coating of appressed silky hairs, papillose beneath and with spreading hairs on the midrib and main veins; venation dense; hairs with swollen bases. Slow-growing but eventually 2 ft high and more in width. Put into commerce by Messrs Bees, who raised it from seed collected in China. It belongs to P. arbuscula, probably to var. albicans. A.M.T. 1966.
‘Elizabeth’ (“Arbuscula”). – Flowers rich, soft yellow, up to 13⁄4 in. in diameter, very pale on the back of the petals, borne in condensed cymes; segments of outer calyx mostly broad-spatulate and about as long as the sepals. Leaflets five, obtuse, shortly mucronate, the lateral ones more or less elliptic, 1⁄2 to 5⁄8 in. long, sparsely covered with appressed silky hairs above, densely coated beneath with erect or spreading hairs, which, like those on the petioles and stems, have a swollen base. Of bushy habit, to about 3 ft high, flowering at the end of every shoot for about five months, and one of the most delightful and useful of dwarf shrubs, though rather subject to mildew (and see the remarks in the introductory note). A.M.T. 1965.
The origin of ‘Elizabeth’ has not been ascertained. It was originally grown as “P. arbuscula” and has been in commerce under that name since the 1950s or perhaps earlier. It was named ‘Elizabeth’ by Messrs Hillier, but it is possible that this name is now used for two very similar clones. ‘Elizabeth’ is probably a hybrid between P. arbuscula and P. davurica var. veitchii. See also ‘Longacre’.
‘Farreri Prostrata’ (“Pyrenaica”). – This name covers two clones descending from plants raised from Farrer’s Kansu seed. One (not seen) is described as being completely prostrate, with rather small flowers, the other low and spreading, about 11⁄2 ft high, 3 ft wide, with flowers about 11⁄4 in. wide, buttercup-yellow in both cases. Neither is common in cultivation. For the name “Pyrenaica” see P. fruticosa var. pyrenaica.
‘Friedrichsenii’ (‘Berlin Beauty’). – A putative hybrid raised in Späth’s nurseries from seeds of a plant of P. davurica (glabra) growing in the Copenhagen Botanic Garden, and described by Koehne in 1896. He considered the pollen-parent to have been P. fruticosa, which seems very likely. Several plants were raised, so the name is not clonal, but according to Koehne they were all very similar. ‘Friedrichsenii’ is little cultivated in this country and is inferior to ‘Moonlight’. It makes a large shrub, with leaves resembling those of P. fruticosa but lighter green, plane, with the lateral veins scarcely raised beneath. Flowers light yellow. The plant examined by Bowden (op. cit.) was diploid, so the pollen parent must have belonged to the subsp. floribunda; typical P. fruticosa would produced a triploid.
‘Ochroleuca’ is a seedling of ‘Friedrichsenii’, raised by Späth, described as having creamy-white flowers and bright green leaves. Plants seen in cultivation under this name have flowers coloured as in typical ‘Friedrichsenii’. Späth also raised and propagated a white-flowered seedling – ‘Beanii’ (P. fruticosa friedrichsenii leucantha Späth; P. fruticosa var. leucantha Bean, not Mak.; P. fruticosa f. beanii Rehd.). It is doubtful whether the true clone is in commerce here.
‘Gold Drop’. – Flowers about 7⁄8 in. across in few-flowered cymes, the later crop borne on growths which overtop the first flush. Segments of outer calyx slender, Leaflets bright green, mostly in sevens, sparsely hairy, bluish green beneath, more or less elliptic, about 3⁄8 in. long. Stipules mostly shorter than the petioles, brown. Dwarf, bushy habit. It was originally grown as P. fruticosa farreri and was correctly given a distinguishing clonal name in the USA. See further under P. parvifolia
‘Jackman’s Variety’. – Flowers bright yellow, 11⁄4 to 11⁄2 in. wide, borne numerously in cymes on shoots from the upper leaf axils, on pedicels 3⁄8 to 3⁄4 in. long; segments of epicalyx narrow-elliptic or sometimes wider and bifurcate. Leaves bluish green above, rather coarse, leaflets often seven, the lower four whorled, up to almost 1 in. long and 1⁄4 in. or slightly more wide. A vigorous large shrub to 4 ft high, more in width. The original plant was found in the nursery of Messrs. Jackman in a row of shrubby potentillas grown under the name P. fruticosa grandiflora, and was presumably a self-sown seedling. The parental stock was discarded, so no comparison can be made. F.C.C.T. 1965.
‘Katherine Dykes’. – Flowers canary-yellow, 1 in. or slightly more wide, in small condensed cymes, very freely produced. Leaflets medium green with a slight glaucous tinge, with five or seven leaflets about 1⁄2 in. long, sparsely hairy on both sides. Habit dense, to about 4 ft high, 5 ft wide. Deservedly one of the most popular of the group, this shrub occurred as a self-sown seedling in the garden of W. R. Dykes, and is named after his wife. After the wife’s death, Mrs Gwendolyn Anley was given the choice of one plant from the garden, and chose this. It received an Award of Merit when she showed it in 1944. It is possibly P. parvifolia (from N.W. China) crossed with P. × friedrichsenii (the latter entered into the parentage according to Mrs Anley’s recollection (Journ. R.H.S., Vol. 71 (1946), p. 101).
‘Klondike’. – Flowers 11⁄2 in. wide, deep bright yellow, in dense cymes, tending to become convex as they age; segments of outer calyx linear or oblong-elliptic. Leaflets mostly in fives, bright green above, blue-green beneath, up to 3⁄8 in. long. Raised by Kruyt of Boskoop, Holland, from P. parvifolia var. farreri and showing no signs of hybridity, though the flowers are unusually large. It is taller-growing than ‘Gold Drop’. A.M.T. 1965.
‘Longacre’. – Resembling ‘Elizabeth’, but of lower, more spreading habit, the stems more slender, the foliage a trifle darker, and the flowers not so cupped when they first open. It arose in Northern Ireland as a self-sown seedling in the garden after which it is named, and was put into commerce by the Slieve Donard nurseries. A.M.T. 1965.
‘Manchu’ (“Mandshurica”). Flowers white, up to 11⁄8 in. wide, scantily borne over a long period; segments of outer calyx more or less elliptic, acute, or sometimes broader at the apex and bifurcate, Leaflets five, elliptic, 3⁄8 in. or slightly more long, silky-hairy above, more densely so beneath, lateral veins and cross-veins stout, prominent; hairs swollen at the base, giving to the midrib a decidedly warty appearance. A dense shrub of mounded habit, not much over 1 ft high. It appears to be a dwarf form of P. davurica var. veitchii, possibly introduced by Wilson. It does not belong to P. davurica var. mandshurica (P. fruticosa var. mandshurica Maxim.).
‘Moonlight’ (‘Maanelys’). – Flowers about 11⁄4 in. wide, soft yellow, fading as they age but remaining darker at the centre; segments of the outer calyx oblanceolate, as long as the sepals, enlarging during flowering, often split. Leaflets mostly five, the laterals elliptic, 1⁄2 to 5⁄8 in. long, soft grey-green and silky above, underside whitish, hairy on the veins; hairs swollen at the base. A large, fairly dense shrub 4 to 5 ft high, 8 ft wide, well furnished to the base, flowering from May to July (to September in a good season). Raised in Denmark.
‘Primrose Beauty’. – Flowers about 13⁄8 in. wide, pale primrose with a deeper centre, cup-shaped, flattening and paling as they age, few in each cyme. Leaflets five, those of the lower pair rather broadly elliptic or slightly obovate, up to 1⁄2 in. long and 1⁄4 in. wide, grey-green and very silky above, undersides densely hairy, papillose; hairs with thickened bases. Of dense, picturesque habit, up to 4 or 5 ft high and 6 ft or so in width. Raised by Cannegieter of Hattem, Holland. It shows some affinity with ‘Vilmoriniana’, but is a far better garden plant and perhaps the finest of all the garden hybrids. A.M.T. 1965.
‘Sandved’ (‘Sandvedana’). – Flowers ivory-white, about 13⁄8 in. wide, short-stalked. Leaflets mostly in fives, sparsely hairy, pale grey-green beneath, about 3⁄4 in. long, rather narrow. A bushy shrub to about 3 ft high, raised in Norway.
‘Tangerine’. – Flowers 11⁄4 in. wide, medium yellow more or less flushed with orange-red or sometimes evenly coloured tangerine red; segments of outer calyx oblanceolate-spatulate, as long as the sepals. Leaflets five, sometimes seven, oblong-elliptic or oblanceolate, obtuse, about 1⁄2 in. long, medium green above, grey-green beneath, sparsely hairy on both sides. A low, spreading shrub up to 2 ft high, 4 ft or more across. The flowers are striking but are never produced in quantity at any one time. The colouring is best developed in half-shade and in cool, cloudy weather; in hot, sunny weather the flowers are yellow.
‘Tangerine’ was raised at the Slieve Donard Nurseries, Newcastle, Co. Down. The history of this remarkable plant, given by the late Leslie Slinger, is as follows: In 1928 he found in the nursery an unnamed stock of a shrubby potentilla with golden-yellow flowers and was told by his father that it had been raised from a pinch of seed labelled ‘Potentilla Red Flowered’, which had been sent home by Farrer. Thinking that the parental plant was the result of a mutation which might recur, Mr Slinger raised generation after generation of seedlings and finally one was found which had a distinct tangerine blotch on some of the petals. This was named ‘Donard Gold’; it had a poor constitution, and was hard to propagate. But a batch of seedlings from this plant produced ‘Tangerine’.
As noted under P. parvifolia, Forrest found plants resembling ‘Tangerine’ on the Burma-Yunnan frontier. According to his field-notes under F.25010 and F.26944, Farrer had earlier sent seed from the same locality, though there is no reference to this in Farrer’s published field-notes. ‘Tangerine’ is a fairly good match for Forrest’s specimens under these two numbers.
‘Tangerine’ has given rise to two sports. ‘Sunset’ has flowers of a deeper colour than in the parent. ‘Daydawn’ is a remarkable break, with flowers in which the ground-colour is cream, flushed or overlaid with peach-pink. For the new ‘Red Ace’, see The Garden (Jn. R.H.S.), Vol. 101 (1976), pp. 252-3.
‘Vilmoriniana’. – Flowers creamy white with a yellow centre, up to 11⁄2 in. wide; segments of outer calyx mostly elliptic, up to 1⁄8 in. wide. Leaflets mostly 1⁄2 to 5⁄8 in. long (much larger on strong shoots), broad elliptic, silky and silvery above, densely white-silky beneath. A stiffly erect shrub to 4-5 ft; flowers borne sparsely over a long period. See also P. × vilmoriniana, under P. arbuscula.
‘William Purdom’ (“Purdomii”). – Flowers canary-yellow with a deeper centre, 11⁄8 in. wide, borne in dense cymes at the ends of the laterals from the previous year’s wood, or on continuations of the previous season’s laterals; anthers very small, apparently sterile, Leaflets five, those of the lower pair narrow-elliptic, acute, 1⁄2 to 3⁄8 in. long, bright green above, pale beneath, with a few hairs above on the midrib beneath. A large shrub with erect main stems, about 4 ft high, 6 ft wide. F.C.C.T. 1966.
This potentilla was introduced by William Purdom from Shensi during his expedition in 1911 for the Arnold Arboretum and Messrs. Veitch. It is known as ‘Purdomii’, but is not the same as P. fruticosa var. purdomii Rehd., for which see P. × rehderiana. The present plant shows no obvious sign of hybridity, though it is certainly more robust than the plants from Kansu such as ‘Gold Drop’. It is perhaps the finest of the yellow-flowered sorts. The flowers are of a very pleasing shade – one, too, that shows up better in the garden than the conventional buttercup-yellow.
‘Woodbridge Gold’. – Flowers buttercup-yellow, about 11⁄4 in. wide, borne plentifully for several months; pedicels very short. Leaflets five, sometimes three, rich green and rather glossy, up to 5⁄8 in. long, 1⁄4 in. wide, narrowly oblong-oblanceolate. Low-growing, to about 2 ft by 3 ft. A.M.T. 1965. Raised by Messrs Notcutt.