Our Life in Gardens Read online

Page 7


  The genus Colchicum includes approximately forty-five species native principally to stony hillsides around the Mediterranean, but extending well into northern India and even western China. (The genus name is classical, from Colchis, the ancient Roman name for the Black Sea region of Georgia.) In their native habitats, one species or another will be in flower from August to April. Still, the bulk of the genus flowers from mid-September to early October. They are all a play on shades of lilac mauve, some deepening almost to magenta, others washing out to pinkish gray. There are a few doubles and a sprinkling of precious albino whites. All are beautiful in their subtly different ways, and all are gifts, for the time in which they bloom.

  The first colchicum to appear here is C. agrippinum, showing its flowers just as the August drought gives way to September rains. Each flower is checkered over, the deeper mauve ground hashed with lighter lines. Botanists call this pattern “tessellation,” and it is most familiar to gardeners on the petals of the snake’s head fritillary, Fritillaria meleagris. Do not, however, expect too much precision in this design. For if dishevelment is part of the charm of autumn, it is certainly part of the charm of colchicum, and C. agrippinum possesses that to a rather large degree. Its six or so pointed petals stand about four inches tall, when they don’t flop over, and the pattern is often blurred to dots. Still, it is beautiful. And the first.

  On the heels of C. agrippinum is C. byzantinum. A much more vigorous species, it can produce as many as two dozen blooms from a single bulb, each standing five or so inches tall, and each making way for the next by falling over on its side, a habit that irritates tidy gardeners. The petals are rather watery, and so the effect of a bulb in bloom is of a puddle of soft pinkish lilac, or when several bulbs are grown together, a pond. A very fine white form exists (C. byzantinum‘Album’) that is equally vigorous, and manages somehow to be a little more upstanding. We have planted both in adjacent drifts, for the white is very clear and pure, and the lilac very moody and autumnal, and each seems prettiest when allowed to create its own effect.

  Sometime in early October, just as the woods that surround our garden turn to their full autumn splendor, C. speciosum comes into bloom. To say that it is the most commonly cultivated species is not to detract from its great beauty, for it is perhaps the jewel of the genus. It bears the largest flowers of all, chalices up to seven inches tall, with oval, rounded, overlapping petals clasping yellow anthers. Buds emerge pale ivory, but quickly color up to a rich, pinkish purple. And though flowers are not born in the profusion of C. byzantinum, their size and the intensity of their color more than make up the difference. Surprisingly, this colchicum is fragrant, though the great early-twentieth-century gardener E. A. Bowles found in its scent an underlying smell “like that of a stable.” No flower is perfect.

  But as close to perfection as one can get is the white form of C. speciosum, C. s. ‘Album’, which is the pearl of the genus. It is pristine white, a beautiful cup of six petals held perfectly upright, no matter what insults autumn storms may deal. It is odd anywhere in gardening to find the albino form of a flower with more substance than its colored counterpart. Here, however, it is so, and this might be the colchicum above all others to plant, were they not all so wonderful in different ways. We have no idea whether it also smells of stables, but if it did, it would hardly matter.

  The last of the commonly cultivated colchicum to bloom is C. autumnale. Actually, however, though it usually brings up the end of the parade just as autumn leaves begin to fall here in mid-October, it sometimes gets out of step and overlaps its cousins. It is a neat plant, producing six or so blossoms about five inches tall, all at once from each bulb, a tight little bouquet. Though other colchicum show off best on bare ground in bays of shrubbery or the sunny edges of woodland verges, C. autumnale always looks best in rough grass, as its popular name, meadow saffron, indicates. It is an effect we would love to have here, but as we have no rough grass except the high, rank growth of the meadow that gets brush cut at just about that time, all our C. autumnale mingle with our other colchicum in one great sweep. There is a very fine white form of C. autumnale also, ‘Album’, which again is best kept adjacent to, but not mingled with, the rose magenta of the typical form.

  We have somewhat ambiguous feelings about the three double forms of colchicum, ‘Waterlily’, ‘Pleniflorum’, and ‘Alboplenum’. All three emerge quite late, as if their quadrupling of petals required more energy to push above ground. Because the essential form of a colchicum flower is so elegant, they can all look rather odd, like penwipers, and it must be said that their numerous petals seem to attract the splashed mud of autumn rains. For this reason, we grow all three of them far away from their slim relatives. ‘Waterlily’ is planted in an open bay of the rhododendron garden, where its many pointed petals of lilac pink bunch tight against mulched ground. ‘Alboplenum’ is similar in form, but snow white, and its flowers rise higher and tumble over quickly from their own weight. It grows in an open patch of one of our woodland walks, where, if we forget to visit it, we find it no great loss. ‘Pleniflorum’ grows in the rock garden, surrounded by gravel mulch, where its pale lilac blossoms are actually quite beautiful.

  There are gardeners—and we are unabashedly among them—for whom the knowledge of a genus of mostly hardy plants of easy cultivation and aristocratic demeanor, with subtle permutations from species to species, creates an insatiable appetite. Give us two species within any such genus, and we must have them all. Rarer species and hybrids begin to appear each year on the more adventurous bulb lists. There are dainty colchicum like C. baytopiorum, whose flowers are half the size of those of C. autumnale and would be wonderfully suitable hovering against a granite stepping-stone. There are even colchicum that flower in spring, C. hungaricum being perhaps the easiest, producing up to eight goblet-shaped pale, pinkish-mauve, three-inch-tall blooms per bulb. A rare white form of it also exists.

  But perhaps the rarest of the spring colchicum is the only yellow-flowered species in the genus. Colchicum luteum is native to northern India into Tibet. Though said to be abundant there, and hardy to Zone 4, it is perhaps the rarest in the trade. We are certain to run it down, sooner or later.

  CORYDALIS

  FEW GARDENERS can resist a fern, or something that looks like one. So all by themselves, the delicate, finely divided leaves of corydalis always win hearts. But unlike ferns, corydalis produce dainty racemes of four-petaled tubular flowers that look like little stretched-out snapdragons, or possibly like schools of tiny fish swimming just above the leaves. Their delicate beauty suggests fine porcelain or a rare botanical print. Even the name (pronounced co-RI-da-lis) is pretty, from the ancient Greek word for “lark” because each flower bears a nectar spur at its base that resembles the spurred feet of that bird. Collectively, the genus carries the very old popular name Fumitory, from the Latin fumus terrae, “smoke of the earth,” because the leaves of many species are a delicate shade of blue-gray or purplish blue.

  Many corydalis are notoriously cranky to establish and keep in the garden. But fortunately, many years ago, we started out with Corydalis lutea, one of the prettiest and easiest to grow. It produces clumps of ferny leaves about one foot tall, and its three-quarter-inch-long flowers are a blend of yellow and white, like quickly scrambled eggs. It is never so happy as when it can find a crevice in an old stone wall, where it will flourish seemingly only on dust and air. In fact, however, old stone walls usually have a core of rich humus within, made up of years of decomposed leaves and debris falling on and through them. We had no such walls on our property, but we knew how to fake them. And we had plenty of fieldstone, usually at least one with every shovel-thrust into the dirt. So we constructed wall beds—”planted walls” as they are called by rock gardeners—across the front of our lower greenhouse and on its shady side. The stones are essentially a veneer, behind which is a core of stiff gravelly soil. The lichens that come quickly on exposed fieldstone increase the impression that the walls are ver
y, very old.

  We planted a single C. lutea halfway up the wall on the shaded side of the greenhouse, since we had read that it would flourish in cool, shady rock crevices. All corydalis are unwilling transplanters, and the usual advice is to buy a plant, set it in its pot near a likely place, water it all summer, and wait for seedlings. But we were impatient, and more than a little cocky in our confidence, so we gently bare-rooted our first specimen and planted it directly in the wall as it was built. By luck or skill (probably the former), it took hold, grew vigorously, and within a year or two, small plants began showing up in other crevices along the wall, not only on the shaded side but also across the sunny greenhouse face. For once a single plant is well established, C. lutea is uncanny at finding the places it likes to grow. It has even made its way, somehow, up the whole length of the property to appear in the low retaining walls of the perennial garden. Experienced gardeners of a snobbish bent call it a weed because of its promiscuity. But if that is so, it is such a pretty weed that we are content to let it come where it will, most of the time. We yank it out only when its ferny growth, light as it seems, threatens to smother out a more precious plant.

  Corydalis ochroleuca is quite similar to C. lutea, though it bears slightly pendulous flowers of creamy appearance, with more white than yolk in them. It is also as easy to grow, though it so far sits comfortably in a trough garden in back of the house and refuses to produce seedlings. We are sorry for that, because the two plants grown together would be a wonderful blend of creamy white and light yellow. A magical effect is always created when flowers of two or more closely related shades mingle. Perhaps it will happen yet.

  There are seventy species in the genus Corydalis, most of which share the family birthright of grace and beauty, but many are very rare and can be quite fussy if their preferences are not exactly suited. Those preferences are usually—not always—for deep, humus-rich woodland soil that is constantly moist but never waterlogged. Light, dappled shade is best, such as would be provided by high old trees, but sometimes the canopy of a large shrub provides a perfect spot. They are not greedy feeders, and so fertilizers should be withheld, especially granular ones that can burn their sensitive roots. Still, a very dilute wash with liquid fertilizer, such as Peters 20-20-20, at half the strength called for on the package, can often encourage weak plants to catch hold and thrive.

  Among the true woodland species, C. cava is the easiest to grow, producing airy, blue-green, fringy leaves topped by cobs of flower of a haunting misty lilac, making it seem especially fumitory. Even in the cool, moist shade it demands, it is apt to melt away in summer heat, causing anxious gardeners to fret. But it will usually reappear with the cool rains of either autumn or the following spring. Corydalis solida differs from it in that its tuberous roots are solid rather than hollow, a trivial botanical distinction that would not prevent most gardeners from thinking it just as wonderful. In the “pure” form (if such actually exists), it shares the predominately lavender or purplish color of C . cava, though it has given rise to many wonderful seedlings and crosses with pink, cherry-red, or even coral-colored flowers.

  Corydalis dyphilla is also irresistible, not so much for its leaves, which are the least delicate of all, as for its upended dancing flowers. They appear in mid-spring, colored a pale whitish mauve with violet-purple lips and throat. Each flower, hardly an inch long, is carried loosely above the foliage in a panicle of six or eight others that seem to nod to one another in curious animation. All corydalis require good drainage at their roots, but give this one the best gritty soil you have, in light shade or morning sun.

  As corydalis gain in popularity, more species and hybrids seem to appear each year. Among those recently made available, the present aristocrat is C. flexuosa. For one thing, its flowers are an electric blue, produced in late spring above foot-tall fringy growth, and to many gardeners blue is the best color a flower can come in. Several selections have been made, of which the best are ‘Père David’, with turquoise flowers; ‘Blue Panda’, almost gentian blue; and ‘China Blue’, with royal blue flowers animated at their tips by a spot of purple and white. More than one gardener has noted that the flowers, with prominent upturned spurs and flared mouths, resemble a school of tiny, vivid blue tropical fish. We have grown them all, but we’d have to confess, not as well as we would like. Our best claim would be, perhaps, that they persist here, offering us enough encouragement to keep trying. Give all forms of C.flexuosa the coolest, richest spot in the garden, in moist, dappled shade, and when they go dormant in the heat of summer, pray for their return in spring.

  The Russian C. turtschaninovii, though impossible to pronounce, is far easier to grow. At its best, as in the collected form ‘Blue Gem’, the flowers are bluer than any gentian or delphinium. In ‘Eric the Red’, the blue flowers are set off against copper-hued foliage for a frankly breathtaking effect.

  Among the blue- or purple-flowered corydalis is the nicely named ‘Blackberry Wine’, which was introduced only in 2001 but has quickly become a sensation. Its name serves it well, for its flowers are a complex blend of deep and pale purple shading to blue. And though many corydalis possess a slight, delicate fragrance, ‘Blackberry Wine’ is rich in scent. To all its other virtues it adds ease of cultivation. Its parentage is vexingly uncertain, though its tolerance of heat and sun suggest our old friend C. lutea. If that is in fact one of Blackberry Wine’s parents, whether it will seed about as freely remains to be hoped for.

  Most corydalis cultivated in gardens are perennials—or at least, you hope they will be perennials—but the genus contains annual and biennial species as well. Among the annuals the most charming is C. sempervirens. It is a much-loved native American wildflower with a range from Nova Scotia to Georgia, and the only corydalis we know of that has its own popular name, rock harlequin. It is typically found growing on thin soils atop rocky ledges, but once established in gardens, it faithfully returns from year to year, its airy sprays of flower appearing on delicate, ferny plants up to two feet tall. The flowers are an engaging blend of color, each tube beginning pale yellow and then transitioning into hot pink, just the sort of costume Harlequin might wear.

  All these corydalis grow in our Vermont garden, so their hardiness extends northward at least to a cold Zone 5, but southward only to Zone 7 or so, for they all dislike summer heat. Their greatest enemy is heavy clay, all too common in the upper South, the Ohio River Valley, and parts of the Midwest. If we gardened in those areas, we would have a bucket of sharp builder’s sand ready to dig into the soil while the corydalis was still in its nursery can. Digging in a bucket of good compost or well-rotted cow manure is also always a very good idea, anywhere. All this is trouble, of course, but corydalis are worth it. For some, such as the wonderful coral-flowered C. solida‘George Baker’ that has (so far) eluded us, we would dig in pearls, if we had them.

  CYCLAMEN

  AT NORTH HILL, from earliest September to late in April, the most watched and watched-over part of the whole garden is actually indoors, in a small quarter of the lower greenhouse. On its bench lives our collection of cyclamen, which includes many of the nineteen or so species in the genus. Cyclamen grow outside too, in the open ground, but sadly, only one species is truly hardy in Vermont, the ivy-leaved Cyclamen hederifolium. Though all the others relish a cool winter when they are in active growth, they need protection both from the arctic cold that sweeps over Vermont in winter and from its lush, wet summers. That is because all cyclamen are native to the Mediterranean basin—southern Europe, Asia Minor, and northern Africa—and so, like all denizens of that world, they want a wet, mild winter balanced by a dry, baking summer. Fortunately, plants that crave a summer dormancy are among the easiest tender plants for the northern gardener to grow, since during the most active part of the year they can be stood outdoors in a dry place or left in pots in the then-emptied greenhouse. Ours remain just where they have lived out most of their long lives, in their section of the front bench in the lower greenhou
se. There they sleep out the summer from late June until September, with no foliage, very little water, and internal temperatures that may reach 100 degrees on a hot summer day. Since the Aegean is not close by, that greenhouse is as near to Greece in the summer as any place in Vermont might be. Or Corsica, or Libya, or Lebanon, or Turkey. The comparison is even reinforced by an old potted grapevine, ‘Datier de Beyrouth’, which is trained up into the eaves and casts a light transparent shade over the bench.

  Cyclamen are such tractable plants that we wonder why more northern gardeners do not collect them. But though ease of culture is always a plus for any plant, it is not the main reason we grow them. Quite simply, they have a charm all their own, with small dancing, inside-out flowers tinted white, pale pink, or deep rose, held pertly on long stems above their beautifully patterned foliage. Many of them are intensely fragrant, to the extent that when we open the greenhouse door on a wintry day, we become lighthearted. It is a complex fragrance—sweet, certainly, but with strong hints of fresh-cut lemons and honey. It is unmistakably Mediterranean.

  All cyclamen are variations on a theme, differing one from another mostly in small but significant ways. Our friend Ellen Hornig, at Seneca Hills Rare Plant Nursery (from which some of our best have come), compares them to snowflakes, no two of which are alike. Our collection of fifty pots or so resembles a little village, where each face is recognizable both for its family relationships and its uniqueness. Each small clay pot, never more than six inches across and sometimes just two, contains an individual, with its own distinct personality and its own way of being in the world.