To most people, the name bellflowers mean campanulas, but the late L. H. Bailey expanded the term to include, too, those other members of the family whose flowers are also bell-like the ring bellflowers, such as (Symphyandra), the lady bell (Adenophora), the trailing bellflower (Cyananthus), the balloon-flower (Platycodon), the grassy bellflower (Edrianthus), the bonnet bellflower (Codonopsis), and other sorts that are not so hardy.
Many of these deserve to be grown more widely, and the qualities that make some of the lesser known kinds so desirable deserve to be known by more gardeners.
More than 200 species of these genera have been offered in the American trade in recent years. Many are commonly known, others are neither so common nor so readily available. Sometimes one must search the seed lists to find an especially desirable item but, next to possessing the rarity, seeking it becomes one of the real pleasures of gardening.
For the most part, this article treats the desirable but lesser known sports. Not every one of them may be available in a given season, but all are known to be grown in our gardens.
Campanulas – Time Tested Border Favorites
Of the common time-tested campanulas there are such perennial border favorites as Campanula lactiflora, long-lived, stately, and most floriferous; the equally large C. pyramidalis, sometimes called the chimney bellflower, with its stiffer spikes and usually shorter lived character; the purple-flowered, clump-forming C. glomerata, long-lived and most dependable, but somewhat less showy than the others, and C. trachelium, a rather coarse, stiff-hairy plant of two to three feet in height, with large tubular flowers that are erect or borne horizontally, a species sometimes confused with the drooping flowered, weedy naturalized “invader” that bears the name C. rapunculoides.
The common rock garden species include the trailing C. elatines, a variable Grecian species of which one minor variant is widely known as C. garganica, and the clump-forming, open-cup-flowered species C. carpatica, whose white-flowered form is as well known as is the blue.
Related to C. elatines, but immature tender is the Italian C. isophylla, usually grown as a window-box or hanging-basket subject. In connection with C. carpatica, it should be noted that most of the material offered as C. reineri is a dwarf race of the Carpathian species.
To C. carpatica belongs also the material passing as C. pseudo-raineri. In true C. carpatica and its allies, the lower stem leaves are heart-shaped or truncate, whereas in C. raineri the lower stem leaves taper basally.
Less Common Campanulas
The less common sorts may be annuals, biennials, or perennials. All are grown readily from seed. None of the annual species equal the others in beauty, although C. macrostyla, of Turkey, is certainly most bizarre, with its shallowly cup-shaped flowers of bright lilac, flecked with white, that open skyward and become two inches and more across at maturity.
In this species, the style extends for an inch or more and is terminated by three large lobes that spread and recurve as the flower matures. It is a curiosity, easy to grow, and certain to attract attention.
A second annual species, showier than the first, is Crassifolia, which grows to six inches in height and spreads by a repeated forking of the gray-hairy branches. The flowers are violet-blue to white and bell-shaped and are produced abundantly in cymose clusters.
Aside from the famous Canterbury bells, C. medium, two other biennial species especially deserve inclusion in the border. One of these is C. formanekiana, a delightful plant, native to northern Greece and Albania. It produces a single stout stein a foot or so high, with a large, pale blue, bell-shaped flower in almost every leaf axil.
It also produces several short prostrate stems about the base, each bearing several flowers. The flowers are of good substance, about one inch long and not unlike those of Canterbury bell. The plant is made further attractive by its soft gray-pubescent foliage and stems.
Sometimes it is distributed in the trade as C. Ephesian and, sometimes too, seed sold under the name C. formanekiana has proven to be the unrelated perennial C. porscharskyana, discussed later in this article.
A second biennial species is C. celsii, another gray-pubescent kind from Greece, where it is native in the Cyclades Islands. It is attractive in foliage because of its lobed to deeply toothed leaves, and especially so in flower for its cylindric-bell-shaped lavender corollas that open skyward and are about an inch long.
The flowering stems may be repent on the ground or ascend to six inches in height. A succession of blooms assures a showy plant for several weeks.
Perennial Campanula Species
With the perennial species, one finds the greatest range of material and the largest number of desirable items. For the rockery, there is the dwarf central European mountain species, C. Alpina.
It forms tufts, producing flowering stems three to six inches in height and a profusion of deep blue, bell-shaped, nodding flowers, about three-quarters of an inch long. Usually, there are three to 12 on each stem.
When in flower, in late May and early June it is a mass of bloom, the narrow-leaved foliage scarcely showing. A colony of five to six plants can be a focal point of color.
Another dwarf member from the Alps is C. alpestris, known also by its later synonym, C. allionii. It is a species whose branching rhizomes produce a dense mat of plants with flowering stems two to three inches in height, each usually bearing a single large erect to drooping blue or white bell-shaped flower that is nearly two inches long.
It requires good surface drainage and establishes itself well in a rock garden pocket if not kept too wet in the summer months.
A neat plant suited for the rock garden or the border is C. barbara. It is distinctive by its very hairy herbage, the basal rosette of spatulate leaves, and the one to few mostly simple stems that arch over at the tip.
In bloom, it is a beauty, with its gray-green foliage and its abundance of bells of lilac-blue or white flowers that droop from long pedicels up and down the stem. Each flower is about an inch long and is usually hairy inside. It, too, is native to the mountains of central Europe.
Two other rock garden species, much resembling C. elatines are C. portenschlagiana and C. poscharskyana. Their long names commemorate those of their discoverers: Father Edler von Portenschlag-Lcdermayer, an Austrian priest who collected extensively in Dalmatia, and G. A. Poscharsky, a plant collector and horticulturist of the Balkans, respectively.
Both species are more or less trailing or with decumbent stems. However, in the first, the corolla is tubular with the lobes about as long as the tube. In C. poscharskyana the corolla is broadly funnelform or the lobes spreading nearly at right angles to the style and are always longer than the short tube.
Both are species of mountainous parts of Dalmatia, with the first occurring also in adjoining Croatia. The latter is sometimes used as a bedding plant in place of C. isophylla mentioned previously.
A Distinctive Bellflower
Among the taller perennial species for the border is to be recommended, C. alliariifolia. Its stems are one and one half to over three feet in height and bear cordate-ovate leaves that are gray-felty beneath. The open raceme hears up to 25 cream-white, long-bell-shaped drooping flowers, each about an inch long.
Plants of this species are also grown erroneously under the names of C. bononiensis and C. saxatilis.
A less showy member of the genus is C. punctata, a species native in Siberia and northern japan, represented in cultivation by at least two unnamed strains or races — one whose large drooping flowers are short-lobed and not much speckled, and the other with similar flowers, bearing broadly lanceolate lobes, which arc much speckled.
These flowers are a muddy, dull, pale reddish-purple basally speckled darker. The stems are about two feet tall and arise from spreading rhizomes — a character that may cause the plant to become weedy.
The common harebell, C. rotundifolia, derives its species epithet from the rounded blades of the rosette leaves — those of the stein are usually grass-like in form. It is a most variable species and to it are allied many species that may be only geographical races, differing by minute characters.
All may be recognized by their foliage, by the slender wiry stems that may be erect or semi-prostrate, and by the small, usually nodding, pale lavender-blue bell-shaped flowers. In this alliance belong most of the plants bearing such names as C. arcuata, C. bellardi, C. caespitosa, C. cochlearifolia, C. heterodoxa, C. hostia, and C. trigionodes. None is particularly striking as a garden subject.
Other bellflowers of allied genera deserve equal consideration with the campanulas. Very distinctive are the sturdy conical-shaped plants of Symphyandra hofmannii, with pale apple-green foliage and a profusion of pure white drooping cylindrical bell-shaped flowers.
The plants grow to about two feet tall. Technically it differs from a campanula in that the anthers are fused in a ring or tube about the style — hence the name, ring bellflower. The plants flourish in my garden as perennials, but some people have found them so short-lived as to treat them as biennials.
Another close relative of the campanulas is the lady bell. These are members of the genus Adenophora — a group of 40-50 species, mostly Asiatic in origin. Much of the material distributed as adenophora represents one or more species of campanula and too often of the weedy C. rapunculoides.
In the flower of an adenophora, there is a globose solid gland situated on top of the ovary and covered by the stamen bases. There is no such gland in any campanula.
A Confused Plant
One of the most commonly grown species of adenophora is Adenophora confusa, and confused it is! The material in the trade under such names as Adenophora Jarreri, A. bulleyana, A. diplodonta, A. marsupial flora, and A. verticillata, all are usually this A. confusa.
It grows to three feet in height and produces, in profusion, a panicle of intensely blue bell-shaped flowers, made more attractive by their recurving sharp-pointed corolla-lobes.
Another desirable species is A. latifolia (whose name often is misspelled Anethifolia). It is of lower stature than A. confuse’ and has paper flowers whose calyx-lobes are toothed rather than entire. Several Japanese species are now becoming available and are to be sought under the names A. remotiflora, A. nikoensis, A. strata, A. Takeda, and A. thunbergiana.
The Siberian — Japanese species A. verticillata is distinctive by its small, but abundant lavender flowers, being borne in whorled clusters about the flowering stem and its branches. It is one of the most attractive of the genus, quite unlike any campanula in its habit and deserving of greater popularity.
The trailing bellflowers are Himalayan perennial members of the genus Gyanantlars. They are prizes of the rock garden and while difficult to propagate, are usually prolific in bloom when well grown. They are low, mat-forming, and bear their deep blue solitary flowers at the end of each branch or stein.
Persons familiar with them should know that the plant cultivated as Cyanantlzus integer is properly C. microphyllus. The true C. integer is not known to be grown here or in Europe.
Other favorites of the rock garden, and I find them a welcome addition, too, in the front of the border, are the species of Edrianthus, the grassy bellflowers. A half dozen or more are in the trade and all are similar in their more or less tufted prostrate habit, with an abundance of grassy-leaved stems about eight inches long radiating from a central crown.
Each stern is terminated by a few too many purple bell-shaped flowers, aggregated into head-like clusters in Edraianthus graminifolius and E. dalmaticus, and borne singly at the stem tips or on short lateral branches in such species as E. primal° and E. serpyllifolia. The plants are perfectly hardy and moderately long-lived.
The Bonnet Bellflower
While almost everyone knows the oriental balloon flower, Platycodon grandiflorum, and its dwarf variety P. g. mariesii, too few persons know the bonnet bellflowers, codonopsis. The latter are species to be admired for their usually scandent to vine-like habit, their delicate skim-milk-blue coloring of the corollas (often suffused with a greenish cast), and the nodding effect of the inverted-cuplike flowers.
They are not suited for cutting, not because of the short flower stems, but because of the musky somewhat offensive odor of the foliage, especially when bruised.
However, they bloom profusely from July through August and I find that, when given the support of some birch brush, they will cover it to a height of nearly three feet, with a delightful mound of soft-hairy foliage by mid-summer. One of the species most commonly grown is Codonopsis clematidea, illustrated at the heading of this article.
A similar dwarf species growing to about a foot high is C. avatar. A species less scandent than the others, and which grows almost erect without support, is C. Meleagris of Yunnan, China. It grows to two feet in height and has the largest flowers of any – about one and one half inches long — that are greenish-yellow in color, flecked and veined with purple over much of the lower half.
No account of bellflowers should omit the beautiful tuber-producing giant bellflower, Ostrowski. A native of Turkestan, it thrives in our Pacific northwest southward to San Francisco, succeeds in Philadelphia and the District of Columbia, but does poorly, and rarely develops to a flowering state in the northeast or central regions.
In Great Britain and throughout south-central Europe it is a garden favorite. It grows from a huge parsnip-shaped tuber, two feet or more in length, and reaches a height of six to eight feet, with a half dozen or more stems arising from a mature five- to ten-year-old tuber.
King of the Bellflowers
The flowers of this bellflower are very pale lilacs, with darker veining, and open to a size of four to six inches across, at first, facing upwards but later nodding with age. The foliage of large whorled leaves is a lovely glaucous blue and provides a conspicuous accent point in the border, even when the plant is not in bloom.
We have flowered it in Ithaca recently, but the plants were small, seemingly lacking vigor, and were not at all praiseworthy subjects. Nevertheless, Ostrowski is the king of the bellflowers and is a “must” for the gardener living in an environment where it will thrive.
Start Them from Seed
Most bellflowers are easy to grow although, as in most large groups, there are the inevitable “difficult species” that challenge the skill of the plainsman. Propagation is generally by seed, but named varieties are usually multiplied by cuttings or by division.
Most perennial sorts will flower when a year old, but some require two full years from seed, and Ostrowski plants rarely blossom until four or five years old. One concern of which the bellflower enthusiast is spared is that of noxious insect pests and diseases.
There just do not seem to be any that favor these plants. When next you order some seeds, seek some of the less common, but truly attractive members of this bellflower clan.
44659 by George H. M. Lawrence