Asia, not Europe, is the center of these elegant woodland perennials BY DANIEL J. HINKLEY
THE GENUS PARIS comprises a group of woodland perennials with an elegant and understated allure that stirs the blood of serious gardeners. Although the name of the genus is identical to that of the French city, they have different origins, the plant genus having been named for its equal numbers of floral parts and leaves (from the Latin par or paris, meaning equal), whereas the city received its name from the Parisii, an ancient Celtic tribe. Closely allied to the genus Trillium and assigned to the family Trilliaceae, Paris occurs only in the Old World, and is geographically centered in China, with 23 of the 26 known species occurring within its borders, and 12 species endemic to that country. Only two species occur in Europe.
Though there are significant differences between the species, all exhibit an arrangement of foliage and flower that makes virtually any member of the genus recognizable. The single flowers are borne slightly above a whorl of four to ten leaves on stems from six inches to six feet from early to late spring. The flowers are composed of broad green (occasionally white) outer tepals and (in most species) threadlike, golden inner tepals. Yellow anthers surround a globular pistil of green, violet, or (rarely) white.
THE EUROPEAN SPECIES
Paris quadrifolia is the type species, usually more highly esteemed in homoeopathic medicine than in the garden. It is common in cool, moist woods throughout most of northern Europe, Siberia, and northern China, where it has garnered such vernacular names as true love, one berry, wolf berry, and herb paris. The four (or occasionally five) broadly ovate leaves of the species are borne atop stems to six inches, capped by diminutive flowers of green outer tepals and wispy greenish white inner tepals in May and June. Pollination is effected by flies attracted by a reportedly disagreeable smell, and is followed by striking, plump, dull blue berries.
The other European representative of the genus occurs further to the east, where I have observed it in the Pontic Alps of northeastern Turkey. There, P. incompleta grows at rather high elevations, always in association with the Oriental beech, Fagus orientalis. Whorls of five to nine narrow leaves are carried atop stems to one foot, while the flowers rising slightly above, as its specific epithet implies, lack the whorl of inner tepals. The fruit is a simple berry of glistening purple black.
How to Grow and Propagate Paris
PERHAPS BECAUSE OF THEIR SCARCENESS IN CULTIVATION, paris have garnered an undeserved reputation for being difficult and resentful of disturbance and division. In the cool, moist climate of the Pacific Northwest, the genus presents few challenges. I cultivate a large collection of Paris species in well-drained, humus-rich, slightly acidic soil under a high overstory of Douglas firs, and similar woodland conditions would seem the best bet in other parts of the country. However, I have also encountered thriving specimens sited in full sun and growing in clay soils in southeastern England.
Plants can be propagated by seed or division, though the latter is much easier. (Like trillium seeds, the seed of paris possesses a double dormancy, and may take up to three years to germinate, with an additional three to five years to first blossoming.) A plant that is dug up in early spring as vegetative growth resumes will reveal an abundance of dormant buds along the rhizome. If a piece of the rhizome with one or more of these buds is removed and replanted, it will usually break growth the same spring, although some divisions may remain dormant for an additional year. Root growth begins in late summer and early autumn, and it is best to avoid disturbing the plants during that time.–D.J.H.
PARIS IN JAPAN AND KOREA
A total of three species of Paris occur in these countries, two of which are quite similar to their European counterparts. Paris tetraphylla is common in the moist, cool mountains of northern Honshu and Hokkaido, where it can be found growing beneath dense stands of cercidiphyllums and magnolias in thickets of Aucuba japonica, Skimmia japonica, Pachysandra terminalis, and Trillium tschonoskii. As its specific epithet implies, this species normally possesses four broad leaves atop stems to 10 inches, while the broad outer tepals become strongly reflexed shortly after opening. Upon ripening, the plump, blue-black berry is sometimes accentuated by the outer tepals taking on hues of violet.
Growing at lower elevations, often in valley bottoms, throughout much of Japan, Korea and China, is P. verticillata, which bears false terminal whorls of five to eight narrowly oblong, short-petioled leaves to six inches atop eight- to 16-inch stems. Both the outer green tepals and golden inner tepals become strongly reflexed upon fertilization, which results in a small black fruit.
Like P. quadrifolia and P. tetraphylla, this species has formed sizable stoloniferous colonies in our woodland garden. To my knowledge, this species offers the only double-flowered form of any paris. With a trebling of the outer tepals, P. verticillata ‘Flore Pleno” presents a beguiling display of precious green “roses,” though it is rarely available, and then only for a princely sum.
Paris japonica is certainly the most distinctive of the genus as well as the most challenging to grow. Above false whorls of six to eight broadly ovate leaves appear striking flowers composed of linear white outer tepals and narrow bright golden inner tepals. Paris japonica is found only in the moist, subalpine meadows of the Japanese Archipelago, where it occurs in great abundance. Because of its exacting climatic and soil requirements, most of the specimens purchased worldwide probably fail to establish.
Current taxonomy suggests that six additional taxa within the subgenus Paris occur within China. I suspect that few of these, however, are in commerce under valid names. With that said, I have successfully germinated and brought to flower P. rugosa, a beautiful species from Sichuan Province that possesses four glossy green, somewhat undulated leaves on short stems to five inches. The flowers, of four green outer sepals and golden strands of inner sepals, result in a large, single, succulent red berry.
If the nomenclature of the subgenus Paris is in trouble, the taxonomy of the subgenus Daiswa is in international crisis (See, “Why Botany Matters,” opposite). Enter P. polyphylla. This widely distributed and notoriously variable species has undoubtedly been in cultivation longer than any other paris. Ornamentally speaking, it is truly sensational, though I hesitate to define what actually comprises this taxa. I have encountered vast colonies of the typical Himalayan form of this species, P. polyphylla var. polyphylla, in eastern Nepal growing at relatively low elevations in moist, shaded forests. This form produces a whorl of seven to ten dark green linear leaves held by long purple petioles atop stems to 12 inches. On short pedicels above the foliage, the typical paris flowers of broad green outer tepals and wiry golden inner tepals surround (after fertilization) a swollen, green, berrylike capsule that splits and expands to reveal a treasure trove of brilliant scarlet (occasionally yellow) seeds. It is my experience that the Himalayan populations of this species emerge much earlier in the spring than the Chinese varieties, and are in full blossom by early May in our US-DA Zone 8, maritime climate.
The first paris that I grew under the name of P. polyphylla, however, is an utterly different creature. Often not appearing aboveground until mid-June, the leaves and flowers unfurl like scepters of fine art glass as the stems rise to four feet or more. Ovate leaves ultimately expand to 10 inches in length, while the typical flowers of green and gold remain unblemished for a full four months. I credit this characteristic to the lack of a compatible partner for cross-pollination and hence fertilization, as I have never had seed produced on this clone.
OTHER ASIAN SPECIES
The tallest of all paris I have encountered is P. vietnamensis, from the mountainous region of Fan Xi Phan in northern Vietnam. Here the plants rose to an astounding six feet or more, with substantive whorls of leaves to one foot and large disks of green-tepaled flowers. As it is from relatively low elevations, it is unlikely to prove hardy in temperate climates, though it will certainly make for an enticing candidate for containerization, a method of cultivation to which the genus as a whole seems very adaptable.
Two species in subgenus Daiswa are known for their colorfully veined leaves, intricately netted in silvers and yellows. Paris luquanensis has proven to be extremely gardenworthy, with squat stems to four inches carrying four rounded ovate leaves that appear almost cyclamen-like. The demure flowers, held slightly above this handsome foliage, curiously lower themselves to ground level after fertilization, while offering a startling display of orange-red fruit in late autumn. The foliage of P. marmorata differs primarily in possessing a leaf undersurface of purple red and outer tepals veined in silver white.
Certainly the years ahead will give us a better understanding of the taxonomy and natural distribution of this remarkable genus. Fortunately, we don’t need to wait until then to appreciate its remarkable qualities in our gardens. The genus Paris awaits a wider audience that will soon enough, and for good reasons, be singing its praises. H
For sources of plants featured in this article, turn to page 92.
1. P. rugosa
2. P. polyphylla var. chinensis
3. P. polyphylla var. yunnanensis
4. P. thibetica
5. P. polyphylla var. stenophylla
6. P. polyphylla var. polyphylla
Why Botany Matters
Botanical splitters have attempted to dismember the genus into three separate genera, based on fruiting characteristics. Current thinking, however, favors retaining the original umbrella name while delineating three subgenera: Paris, Daiswa, and Kinugasa. Those taxa with fruit as a single indehiscent berry, either red, blue, or purple black, have been placed in the subgenus Paris. Taxa that possess dehiscent fruits that split in a starfish fashion to expose seed enveloped by a brilliant orange or red aril are assigned to the subgenus Daiswa, while P. japonica, with an intermediate fruit type, is referred to the monotypic subgenus Kinugasa. Though this division may seem overly academic, these characteristics are essential to identifying the species, and are hence of interest to keen gardeners who have discovered the delights of the genus.–D.J.H.
Facts & Figures
TYPE OF PLANT: herbaceous perennials FAMILY: Trilliaceae (trillium family), formerly Liliaceae ORIGINS: temperate Europe to eastern Asia HARDINESS: USDA Zones 5/6–9 (most species) HEIGHT: 6 in.–6 ft., depending on species LEAVES: borne in an apical whorl of 4–10, obovate to linear, acuminate, to 12 in. long, medium green, sometimes variegated FLOWERS: spidery, with 4–8 (usually) broad, green outer tepals and 4–8 (usually) narrow, yellow inner tepals and up to 20 stamens FRUIT: a simple berry or a fleshy capsule containing (usually) scarlet seeds BLOOM PERIOD: early-late spring SOIL: humusy, moisture retentive, well drained EXPOSURE: dappled shade WATERING: not tolerant of drought PLANTING TIME: spring; do not move plants in summer and fall FEEDING: annual mulch of leaf mold (optional) PROPAGATION: by division in spring or ripe seed sown in fall PROBLEMS: none serious