| First described by Thunberg in Transactions of the Linnean Society 2: 327. 1794.
| Sealy (1937) in defining the Iris Watti relatives provided the following description; "Rootstock a rather slender greenish rhizome, prominently marked by the scars of fallen leaves and leaf-scales, bearing roots throughout its length, becoming upturned at the apex when the growing season starts and producing a tuft of leaves, from among which arises a flowering stem. The rhizome grows some distance between the leaves and flowering stem of one season and those of the next, and from the axils of its scale-leaves it may produce thin stolons which grow out some distance (about 10.5 cm) from the parent rhizome and give rise to new plants. Leaves thick, smooth, glossy on one side glaucous on the other, usually 30-40 cm. long, and 1.7-3 cm. wide, but in small field specimens as small as 24 cm. by 1.5 cm, and in cultivation up to 70 cm. by 4 cm. Flowering stem often over-topped by the leaves, usually 30-50 cm. long, but in some field-specimens only 21 cm. long, bearing five to eight branches of which the lowest is sometimes itself branched, and one or two leaves which are 9.5-22 cm. long and 1-1.5 cm. wide, and which pass upwards into the bracts, the latter being mostly 2-5 cm. long; outer spathe-valves 1-1.7 cm. long.This species has much the same habit of growth as I. tectorum, from which it is easily distinguished by its much branched inflorescence, smaller flowers, etc. The relationship to I. Wattii is referred to under that species, and it is quite possible that these two species may have evolved from the same stock, or that one may have originated from the other. The most striking difference between them is, of course, in habit, for whereas in I. Wattii the tuft of leaves is carried some distance above the level of the ground at the end of a leafy stem, in I. japonica the leaves are wholly basal and are bourne at ground level. So far as the inter-relationship of the two species is concerned, however, the habit-character is perhaps not so important as it might seem at first, for it depends solely on the elongation or otherwise of the vegetative axis of the plant. In I. japonica the axis is very short and cosequently the leaves are crowded at ground level, but if we imagine this very short axis growing out a little so that it forms a stem with the lower leaves scattered along it and the remainder of the leaves aggregated in a tuft at its apex, then the plant of japonica would be an exact counterpart of a plant of I. Wattii. I. japonica would of course, still differ from Wattii in its thicker, narrower leaves, smaller bracts and leaves on the flowering axis, smaller spathe-valves, serrate tepals, etc., and the two would still be treated as distinct species. A characteristic of I. japonica is its refusal to set seeds, both in cultivation and in the wild. Dykes mentions one instance where an imperfect capsule with a few seeds of doubtful fertility was formed, but apart from this there seems to be no record of the production of seed by this sp[ecies. According to Dykes, the pollen also in I. japonica is always imperfect. The explanation of these features may perhaps lie in the chromosome constitution of the plant, and it is possible that I. japonica either has an odd set of chromosomes, that is it may be a triploid, pentaploid, etc. or that its chromosome-complement is not quite complete.
| I. japonica is figured in the Botanical Magazine t. 373 as Iris chinensis; Distribution: Japan, China.
| Iris japonica Thunb. [as Iris fimbriata Vent.] Redouté, P.J., Les Liliacées, vol. 3: t. 152 (1805-1816) [P.J. Redouté]
| Iris japonica Thunb. [as Iris fimbriata Vent.] Ventenat, E.P., Description des plantes nouvelles et peu connues, cultivées dans le jardin de J.M. Cells, t. 9 (1802) [Sauvage]
| Iris japonica Thunb. [as Iris fimbriata Vent.] Collection des vélins du Muséum national d’histoire naturelle, vol. 11: t. 62 () [P.J. Redouté]
| Iris japonica Thunb. [as Iris fimbriata Vent.] Mordant De Launay, F., Loiseleur-Deslongchamps, J.L.A., Herbier général de l’amateur, vol. 6: t. 412 (1817-1827) [P. Bessa]
| Iris japonica Thunb. [as Iris fimbriata Vent.] Redouté, P.J., Choix des plus belles fleurs et des plus beaux fruits, t. 46 (1833) [P.J. Redoute]
| Iris japonica Thunb. [as Moraea fimbriata (Vent.) Loisel.] Revue horticole, serié 4, vol. 39: p. 271 (1867) [F. Yerna]
| Iris japonica Thunb. [as Iris fimbriata Vent.] The garden. An illustrated weekly journal of horticulture in all its branches [ed. William Robinson], vol. 28: (1885)PLATE 503. THE FRINGED IRIS OF JAPAN. (Iris fimbriata)The graceful Iris figured in the accompanying plate was first described by Thunberg in 1793, and named by him I. japonica. It must before this have been introduced into England, for Mr. Baker states that the Banksian herbarium contains a specimen from Kew Gardens dried in 1792. Curtis figured it in the Bofanical Magazine, in 1797, as I. chinensis, and in Redoute's " Liliaceae " it appears as I. fimbriata. On the ground of priority, which certainly should in most cases decide a question of nomenclature, the plant ought to be called I. japonica; but I. fimbriata is so happy a term, and I. japonica so little distinctive a one, that I venture in this case to break a wise rule and adopt the name I. fimbriata.In a considerable number of Irises the fall or outer perianth segment bears along the medium line of the claw and the adjacent part of the blade not a beard composed of hairs, as in the ordinary bearded Irises, but a crest — that is to say, a ridge cut up into a number of tooth-like projections. These crested Irises, as distinguished both from bearded Irises and from beardless Irises, in which the whole of the fall is smooth and even, have been classed together in a group under the name Evansia.I have myself some doubts about the validity of this group, since, on the one hand, a crest more or less developed appears in certain bulbous Irises — ex.gr., in the Juno group — while traces of a crest appear in some species whose allies are clearly beard-less; and, on the other hand, the group, thus constituted by the possession of a crest, seems to me to contain plants wholly diverse from each other. Be that as it may, however, the Iris which we are considering now is a crested Iris and belongs to this group of Evansia.It is a native of Japan (middle and southern islands) and of the middle and southern regions of China. The rhizome bears, fanwise, broad ensiform leaves, and sends out numerous runners or stolons, by which it may be rapidly multiplied. The stem, I foot or 2 feet high, is branched, bearing clusters of flowers. The individual flowers are short-lived, lasting only for a couple of days or so, but they are borne in profusion, a well-established plant giving a succession of flowers lasting many weeks. The plate gives a fair idea of the form of the flower, the crisped and broken margins of the falls and standards, and especially the fringed edges of the crests of the styles, justifying the name of fimbriata, or fringed.But it is very difficult to reproduce the charm of the colouring, the delicate light blue-purple or lavender forming the ground colour of the whole flower harmonising pleasantly with the yellow and orange of the crest by help of patches and veins of darker purple scattered here and there. A well-grown plant with several stems covered with these graceful flowers, which make up in delicacy and refinement what they lack in size and depth of colour, is a very acceptable sight; and in a warm atmosphere a slight, but agreeable, fragrance makes itself felt.Although, as I have said, I doubt the solidarity of the Evansia group as a whole, this I. fimbriata has certainly allies. Iris tectorum, also a Japanese and Chinese plant, with its much larger and more gaudy flowers, has many affinities with it; and intermediate between the two comes an Iris which was introduced by seed from the Himalayas by Mr. Frank Miles, and which Mr. Baker proposes to call I. Milesi. And I am inclined to think that the I. nepalensis of Royle, when we come to know it more fully, will also prove a very close neighbour, as indeed does an unnamed Iris from Lahul, which M. Max Leichtlin has kindly given me, but which proves to be a most difficult plant to grow. The I. nepalensis of Don, which is identical with the I. decora of Wallich and with an Iris from Kumaon called I. kumaonensis (which name accordingly ought to be withdrawn), though a crested Iris, differs in most important features from the others just named. Confining ourselves to the narrower group to which I. fimbriata belongs, We thus find that, while its centre is in China and Japan, it stretches away westward to the Himalayas, where it disappears. Strange as it may seem, and yet in accordance with what we know of the laws governing the geographical distribution of plants, we can pick up the group again if, moving eastward instead of westward, we cross the Pacific Ocean and North American continent, for the little Iris lacustris of the shores of Lake Huron and I. cristata of the States of Virginia and Carolina are not only crested Irises, but Irises in their essential features closely allied to I. fimbriata. In accommodating themselves to their American homes they have become dwarfed, though they have not lost all their beauty. The effects of conditions of life are still further seen in the little I. verna of the more northerly Eastern States, for this seems to me to be in reality a crested Iris which has lost its crest. All the specimens which I have hitherto seen of I. fimbriata are exactly alike. I have never met as yet with any distinct variations. I have, however, in my possession two named kinds from Roozen, but as they have not yet flowered with me, I can say nothing about them.In this rough climate of England, I. fimbriata — save perhaps in some southern paradisiacal garden, such as that of Mr. Ewbank — must be grown as a cool greenhouse pot plant. Even with me it will live out of doors (I did not try it, however, in the winters of 1879 to 1881), but it only lives. To flower adequately it must have the protection of glass and the help of artificial warmth in winter. In its native home it is found in moist and shady situations, and must not, therefore, be dried off like I. tectorum, which, as its name implies, may be and is grown in its native home on a dry house-top. I have not found it very particular as to soil ; a rich open one, composed of loam, thoroughly rotten manure, a little peat perhaps, and a good deal of sand, seems to me to suit it best ; with too much peat the rhizome is apt to rot. I usually take a runner in winter, grow it on during the rest of the winter, spring, and early summer, shifting it from a 3-inch to a 4i-inch pot, and then to a 5 -inch pot, giving plenty of water and a genial temperature. By that time the pot has become well filled with roots and most of the foliage has been made. I then place it out of doors, not wholly in the shade, but exposed freely to our feeble English sunshine, taking care that it never gets quite dry, but keeping it, as respects water, rather stinted than otherwise during the late summer and autumn. In the winter it comes back into the house; as growth begins again water is given more freely, and, according to the temperature to which it is exposed, the bloom may be expected from Christmas, or even earlier, onwards. If the young plant thus treated does not bloom the first winter, I keep it in the same pot, or one slightly larger only — for it seems to do rather better for being somewhat potbound, provided that it gets adequate nourishment — and subject it to the same treatment. The chief points of culture to be attended to seem to me to be — ample moisture, air, and light in the winter and early part of the year, and a season of comparative, but not absolute, rest during the latter half of summer and autumn. M. Foster.
| Useful Pl. Jap. 3: tab. 935. 1895, illustrated in color.
| Dykes in the Genus Iris, 1913;Description. Rootstock , a somewhat slender greenish-coated rhizome, widely creeping by means of stolons or underground shoots, often 6 in. or more in length. Leaves , ensiform, dark green with a polished upper- and glaucous under-surface, three or four to each fanlike tuft, narrowing gradually to a point 18-24 in. long by 1-2 in. broad. Stem , about 1 8 in. long, bearing many heads of flowers in a regular raceme. Spathes , 3-5 flowered, valves pale green, ½--¾ in. long. Pedicel , about I in. long, triangular in section. Ovary , ¼ in., rounded trigonal, with a shallow groove on each surface, bright green. Tube , ½--¾ in. long, slightly funnel-shaped, white. Falls . Obovate cuneate with a serrated wavy edge. The groundwork of the centre of the haft and of the blade is white, bordered with deep mauve blotches, which fade into the pale lilac mauve colour of the circumference. From the base of the haft there start three parallel ridges. The centre ridge is at first white with an orange tip becoming entirely orange on the blade, where it is covered with fine silky white hairs. The two flanking ridges are white blotched with yellow brown and fade away on the blade, where the central crest becomes conspicuous. I½ in. long by 1 in. broad. Standards , nearly horizontal, oblong unguiculate, with a serrated, and widely emarginate, upper edge, r ¼ in. long by ½ in. wide, pale lilac mauve. Styles , ½ in. long by ¼ in. broad, of a slightly deeper shade of mauve than the rest of the flower. Crests , large, very deeply fimbriated. Stigma , with slightly crenate edge, entire. Filaments , white, longer than the anthers. Anthers , white, not much more than ¼ in. long. Pollen , white, and always so imperfect that I have not been able to determine its shape. Capsule , small, elliptical, ¾-7/8 in. long. Seeds , pyriform, with slight arillus as in I. tectorum.Observations.When well grown, I. japonica is a very decorative plant. The broad dark-green foliage is evergreen with a little protection from severe frost. Unfortunately, owing to its early flowering habit', it is rarely able to produce its blooms out of doors in England. The rhizomes themselves are quite hardy and have even been naturalised in Chitral, where very low temperatures are recorded in winter. I am indebted for plants from this source to the kindness of Major-General Lorne Campbell of Abbottabad, and I had hoped that this undoubtedly hardy strain would perhaps consent to flower in England but unfortunately this has not proved to be the case. Indeed, the plants are at their worst in spring and early summer, when our sun is not hot enough to cause vigorous new growths and flowers to develop. It is true that the hot summer of 191 I ripened the growths so well that the plants were prepared to flower early in 191 2, but the hard frost at the end of January destroyed all the flower shoots while they were quite immature.In spite of the fact that the individual flowers are very shortlived, the number that are produced on each flowering stem make this Iris a valuable cool greenhouse plant, where it does well, either planted out in a border or in pots. Plants cultivated under glass can be given that rest and ripening which is necessary if the plant is to flower.Forms with variegated leaves are known but it is a question of taste whether such monstrosities are really desirable. It is also possible that a pink-flowered form exists in China, if we may trust the colour of a drawing made in that country before 1844 by a Mrs Julia Allport (K). For some reason, this Iris seems very reluctant to set seed. Maximowicz (1. c.) states that he nowhere found capsules or seeds in Japan, and artificial pollination seems useless in England. Sir Michael Foster tried in vain to obtain seeds and my own efforts to fertilise flowers have met with no better success. Dr D. D. Cunningham of Torquay, and his neighbour, Mr Eden Phillpotts, very kindly undertook experiments in their milder climate, but their combined efforts only produced one puny capsule with a few seeds of doubtful fertility. If seed could only be obtained, it is possible that plants might be raised, which would become better adapted to English climatic conditions and give us a valuable garden Iris. Probably, in this case, the greatest chance of success would be to grow the plants in a sunny, sheltered nook in stony, well-drained soil in a rock garden. Even the ordinary form of this Iris is occasionally able to produce its flowers in the open. Instances of this in Jersey and Devonshire occurred in 1912.Cultivation is not difficult and it is possible that the plants would do well in a half shady position among shrubs. The soil should be well drained and not too rich, though care must be taken that the plants are not starved when they have been growing for several years in one position or in a pot.
| Fig. 29. Waddick & Zhao, Iris of China, 1992, illustrated in color;