January thawed
Mild weather brings unusual activity, both distressing and delightful, to the garden
I was in Ireland a few winters ago to visit gardens and soon came to the realization that for all the bone-chilling dampness, the Emerald Isle never loses its green glow.
You will find seemingly delicate plants in bold bloom, including snowdrops, cyclamen and winter aconites, but the vitality flows more from the sense of a whole landscape still radiating life. This extends to the broadleaf evergreens, plump and showy, and the naked twigs of the deciduous shrubs, either glowing in the soft sun or fully budded.
In the Mid-Atlantic, winters used to be predictably long and cold. As this winter has once more demonstrated, we no longer live in such a place. After some November freezes, we have seen a long stretch of above-average temperatures. The mildness has brought about a sort of vegetative awakening redolent of Ireland or other temperate, maritime climes.
The question is, should we worry that this shift is an indicator of destructive climate change or should we revel in its January bounty? The answer is yes, to both.
The idea of planting for winter interest becomes more compelling as the coldest season warms. This year, the displays of winterberry are spectacular, fueled by the abundance of moisture during last year’s growing season. Camellias, too, are having a banner year, particularly the hybrids developed for fall and winter display. If you had three or six in your garden, you would be pleased this winter. So far. Early next week will bring temperatures in the teens, according to forecasts, and this will check much of the display. The Japanese camellias of February and March are plump-budded but seem furled enough to ride out the chill.
Witch hazels are putting their toes in the water. They have the capacity to curl up their straplike petals in a light frost – but once fully open the blooms can perish with a hard freeze.
At Green Spring Gardens in Northern Virginia, the highly fragrant Chinese witch hazels are blazing away, even if the display is lessened by the death grip of brown leaves. Some of the popular Japanese-Chinese hybrids do this, too; when I grew the red-flowered Diane, I would have to cut away the previous season’s withered leaves in advance of bloom time. This winter, the problem is particularly widespread, said Green Spring’s curatorial horticulturist, Brenda Skarphol.
“We had a sudden freeze in November,” she said, which stopped the leaves from aging to the point of dropping.
The witch hazel, though an expansive shrub, is such a lovely addition to any garden that this leaf-clinging can be overlooked if you don’t want to groom it in December. I was struck by a variety named Harry, whose flowers and calyxes were a confetti of yellow, magenta pink and apricot. Another hybrid between the Japanese and Chinese witch hazels, Harry is known for its prolific and showy blossoms. If you want native witch hazels, a species from Mississippi named Hamamelis ovalis and related to the vernal witch hazel is a delightful thing with profuse clusters of spiky, carmine-red blooms. It may be hard to find.
The leatherleaf mahonia is about a month from flowering, as is the Japanese apricot, but a hybrid mahonia at Green Spring, remarkable for its size (15 feet by 8 feet) and named Winter Sun, is on the edge of full bloom.
The gardener is ambivalent about mahonias – they are prickly and coarse to a point where drama touches ugliness – and they get leggy and open. But a compact stand has its textural value, and it is so heartening to smell the primrose yellow blossoms in later winter and to see honeybees drawn to them then.
I have seen daffodils not only up but in full bud, probably February Gold. This is alarming, but daffodils will stop developing when it turns frigid, and the blooms, when they come, will be fine. In my experience, the only worry is if the daffodils are in full bloom when a hard freeze comes along, at which point they will collapse.
The bearsfoot hellebore (Helleborus foetidus) deserves much greater use, with its upright and lacy foliage and early appearance (with a faint, malodorous scent). It likes a little shade and insists on welldrained soil, where it will seed around when happy.
More common are the related Lenten roses (Helleborus x hybridus). It is easy to shear off or even mow the old foliage before the new leaves and flower buds emerge from the ground, but it is too late for that this year. At this point, you have to get down and remove each of the older leaves individually for an optimum show between now and April.
That spiky agave look-alike, the yucca, seems particularly perky. In one bed at Green Spring, you can see the dark, faded inflorescence of Yucca x gloriosaVariegata while the foliage below is fully awake. Strangely, this one flowered in December, Skarphol said. Perhaps it thought the November freeze constituted the entire winter.
Nearby a red-flowered honeysuckle is preparing to flower. Dropmore Scarlet is a hybrid of two native species and worth tucking in a place where it can recede after flowering. As with the trumpet honeysuckle, one of its parents, you have to watch for an impressive buildup of aphids as early as March. Soapy water will send them packing.