Winter-blooming Trees
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The weather of winter 1989 was so disastrous that no flowers and few flower buds survived unhurt by the numbing, frigid temperatures. Fortunately, arctic air is a rare visitor to Puget Sound, so during normal winters, we can enjoy several kinds of blooming trees.
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| Prunus subhirtella |
| Most familiar is the tree that is called both autumn- and winter-flowering cherry (Prunus subhirtella 'Autumnalis'). It is heartening when seen in full bloom of its palest pink flowers against a background of evergreens or dark buildings --in December! When sun rays part our customary gray cloud layer, a landscape of this cherry with an underplanting of shiny, fragrant Sarcococca shrubs is a very real foretaste of spring. The tree aptly signifies "deceit" in the Language of Flowers, and an innocent and welcome lie it is. |
| This atypical timing is the tree's only virtue. As a street tree, against a pale sky, 'Autumnalis' is vapid; up against a white or pale house it is weak. If it were otherwise identical, but bloomed only in March or April with the dozens of other cherries, we would scorn its sparse, pale display, for other spring-flowering cherries offer better floral ornament, with greater strength and constitution. |
| The autumn cherry is one of the weakest, most disease-prone, and frequently the ugliest of trees we grow! For one to be a first-class specimen, it must be scrupulously situated on an ideal site (which most home owners do not have), then painstakingly cared for. It needs a well-draining soil, excellent light exposure and air circulation, and a dark backdrop. Then it must be guarded against canker, blight, rot, and like abominations. This, and the need for pruning dead twigs out, does not make for a low-maintenance tree. |
| When not in bloom, which is from about May through September, it is a delicate, but plain, sight at best, and a rough, ill-favored eyesore more often. In order to shore up its weaknesses, some nurseries graft it high upon an attractive birchbark cherry (Prunus serrula) trunk, thereby giving it a rich, shining red pole upon which it can spread its knobby gray twigs. |
We can sum up the prevailing attitude towards autumn cherry thus: If properly located and maintained it will be a welcome joy during winter --the best of all winter-blooming trees. If planted just any old place, even with spray programs and pruning, it will be at best an expensive, sub-par ornamental. For those of us who do have the perfect site or the patience to baby an inherently weak tree, several alternative choices are better.
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| Punus subhirtella 'Rosea' |
If we insist upon a cherry, none are truly as winter-defiant as 'Autumnalis', but several are indeed late winter to earliest spring in their blooming time --that is to say, they are more harbingers of spring than companions of winter. The best is Punus subhirtella 'Rosea' which is locally known as Whitcomb cherry (and ideally is sold as 'Whitcomb'). In about 1925, David Whitcomb of Woodway Park (northwest of Seattle) supplied nurseries with propagating stock of this tree. Unlike the autumn cherry, it is healthy and strong (in recent years it has been very disease-prone), deep pink in bloom, and easily placed in a landscape. It blooms mid-February into March. The largest specimen known in the state is 32 feet tall and 48.5 feet wide, with its trunk circumference nearly 7 feet. It is a large tree, so use caution by planting it where there is plenty of room.
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| Punus 'Okamé' |
'Okamé' cherry is a hybrid between the Japanese Mame (Prunus incisa) and the red-flowered Taiwan cherry (Prunus campanulata), which arose in England before 1944. From late February through March it displays a spectacle of clear pink, dainty flowers on an irregular, intricate crown. It is of average strength, but has to be planted much more extensively before firm judgments as to its virtues and vices can be made. The specimens in the Washington Park Arboretum are the only old ones known around the region. Only in the last few years has 'Okamé' been available in the Pacific Northwest wholesale nursery trade (it has proved disease-prone but offers winsome fall color). Because its twigs tend to be rigidly congested, it is best used as a background tree for an early explosion of color.
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| Cornus officinalis and Cornus mas |
| A truly flawless tree is needed for a more prominent site. A flawless ornamental tree! What? Does such a thing exist? What are we seeking? How about attractive flowers; attractive foliage; attractive bark; attractive branch structure; attractive fruit; blazing autumn color (if it is deciduous); pest and disease resistance; ease of propagation, transplanting, and siting; and climatic adaptability --no watering needed in summer, no worry of winter damage. |
| Let us go all out and ask, if possible, for fragrance and an uplifting, moving "aura"! None I know fits this "Cinderella's slipper." But it has been said "aim high to hit the mark." Many of the listed attributes are united in Cornus officinalis, the Chinese Cornelian Cherry. It lacks fragrance and blazing fall color, and will not inspire us as can a noble American elm. However, the fruit is edible, and the rarity of the species in cultivation should also be an incentive to grow it, for it is always a pleasure to grow a plant both choice and scarce. |
| This tree is larger and better than its familiar European cousin the Cornelian Cherry (Cornus mas). But both species bid adieu to winter by bedecking their dark slender twigs with a bright display of clear yellow flowers --small in size, delicate in parts, yet freely borne and more showy than witch-hazel blossoms. |
| In Seattle Cornus mas flowers appear sometime from late January through March, usually in February. Then the leaves flush as the flowers fade, and until the fruits darken in August, the aspect is best described as quiet; people neither stop and stare admiringly, nor avert their eyes and flinch. The "cherries" ripen for eating between mid-August and early November; the bulk of them are eaten by birds between August and early October when they change from shiny green to deep crimson and become very juicy. Each is oblong and has a single large stone. Seedlings are easily found. |
Cultivars of the Cornelian Cherry with large, abundantly-borne fruit are being imported from Bulgaria. These will be both more ornamental and of value to those of us who enjoy growing unusual edibles. The trees are just right for most city lots, because without decades of growth and some shade they are rarely seen 30 feet tall. The wood is slowly added and very hard. The Chinese species grows larger, has larger flowers and leaves, produces more attractive bark, and blooms a bit earlier in the year. But it, as well as the large-fruited European cultivars, is presently almost impossible to obtain. For now, most of us must be content with ordinary old Cornelian Cherries.
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| Azara |
| Chile and Argentina are home of the boxleaf Azara (Azara microphylla), or chinchin, as it is known there. A slender, delicate, tiny-leaved broadleaf evergreen that is usually seen less than 20 feet tall, it makes an arching, semi-pendulous crown that is airy and sparse, except on the healthiest specimens. The sparkling little leaves are about a half-inch long and are strung along thread-like twigs. Complementing the leaves are similarly minute yellow flowers, which scent the air deliciously of vanilla sometime between December and April (chiefly in February or March). |
| Tiny quarter-inch long berries, at first a reddish-orange color, ripen in June or July to the color of chocolate milk, yet shiny and speckled. They are one-seeded and taste faintly of bitter vanilla. |
The azara is reasonably hardy, yet exposed specimens are noticeably hurt in our severest winters. The plant is perfect for the fragrance garden, and not bad for beauty. Its flaky cinnamon bark is attractive, and its variegated cultivar is a knock-out beauty. It can grow without irrigation, and in full sun or considerable shade, but is best in a rich soil, with partially full sunlight and some protection from cold winds.
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| Loquat |
Loquat (Eriobotrya japonica) is most often regarded as a fruit-producer or as a bold-foliage ornamental, but it also bears dense clusters of creamy white flowers sometime between November and February. They are not an eye-arresting delight, but seen at that time of year, and against a contrasting dark background of large, rugged, evergreen leaves, they are conspicuous (and modestly fragrant). In June or July the delicious orange fruit ripens. Loquat grows lusher in shade, but fruits best in sunnier exposure. It is a large shrub and eventually can become a tree to about 30 feet tall.
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| Pussy willows |
| Another winter-blooming tree is one of the native pussy willows (Salix Hookeriana). This species is associated with proximity to salt water, and has been called accordingly the shore, coast, or beach willow. In the wild, it extends from southern Alaska to northwest California. Setting it apart from the various other pussy willows are its relatively large leaves, which are deep glossy green on top and white woolly beneath. They can measure up to 7 inches long by 3 inches wide, and are preceded by equally outsized catkins, borne on stout velvety twigs. The tree can reach 40 feet in height or can be kept pruned to shrub size. Unlike many pussy willows, it is definitely a tree, well-trunked, rather than merely a scrawny collection of slender stems. It is rarely galled or disfigured by ugly fungal spots and is a very good species for garden usage (though less disfigured than Seattle's other native pussy-willows, it can become blighted, and like the other species is short-lived). |
| Another rare pussy willow is also worth further planting. This is a European hybrid properly called Salix x sericans (S. caprea x S. viminalis), but usually called in America Salix x Smithiana (S. cinerea x S. viminalis). The leaves are long and pointed, up to 6 by 1.5 inches, and are ruggedly textured, dark green above, and gray fuzzy beneath. As with the Hooker pussy willow, they are also borne on stout, felty twigs and are resistant to the problems besetting the common native species (chiefly Salix Scouleriana). They are not as plain, small. and crinkly as those of the "French Pink" pussy willow (S. caprea). |
| This great rarity came to my attention as I chanced to be walking through an alley on Seattle's Queen Anne Hill. It clearly was a willow, but I had no idea what kind, having never seen anything like it before. It stood about 35 feet tall and wide, and its trunk was over 8 feet around (in 1988. It was cut down in 1990). Inquiry revealed that it began life as a twig in a 1958 Valentine's day bouquet! |
Winter here is usually December and January, and the trees just featured are about the best we have for flowers then. Many shrubs are equally valuable or better. For example the Chinese witch-hazel (Hamamelis mollis) and Japanese osmanthus (Osmanthus heterophyllus) are richly fragrant, highly desirable, and can become trees. Beginning in February, an array of colorful plums, apricots, almonds, and cherries (all manifestations of Prunus) come into bloom, along with the earliest magnolias. Golden, dainty hazel catkins, the dusty pollen of some conifers, and many other natural signs, all proclaim resurrection.
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(Originally published in the Winter 1989-1990 Washington Park Arboretum Bulletin.)
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