December 26, 2009
It's the time of year our homes are decked out for the holidays, perfumed with the fragrance of live greens - spruce, firs and pine trees, cedar swags, colorful wreaths - a mixture of all. We relish the sensory delights these plants provide for their short stint indoors, then, come January, we pretty much forget about them for another year.
These oft-neglected garden plants are conifers, a group of generally trouble-free plants with tough constitutions that need little care to keep their good looks throughout the seasons. They have so much to offer, they're worthy of a place in your garden - especially the dwarf varieties that grow slowly and take up much less space, water and nutrients.
Conifers, known botanically as gymnosperms, are plants that bear cones. Native to the earth's Northern Hemisphere, the majority are evergreen with thin needles, or scalelike leaves that help reduce moisture loss and shed snow easily. If you think of conifers, you may conjure up visions of towering trees atop snow-covered mountains, majestic redwoods along the trails of Muir Woods or the ever present utilitarian junipers lining the front yards of entire neighborhoods. And while they are the oldest, tallest and most massive trees on the planet, they're a lot more than that. You can find them in an amazing range of forms, colors, and sizes - from the gargantuan, such as the General Sherman tree (Sequoiadendron giganteum) in Sequoia National Park, with a mass of more than 52,000 cubic feet, to tiny miniature plants such as Picea abies 'Thumbelina' that grows just a bit bigger than a large grapefruit.
"Far from being dull," writes renowned horticulturist and author Adrian Bloom in his book "Gardening with Conifers," "to the observant this group of plants can be both awe-inspiring and magical."
In the garden, conifers provide a rich tapestry of structure, form and color especially this time of year when the luxurious growth provides a striking accent to an otherwise wintry scene. And dwarf conifers can accentuate the tiniest garden space - even a container. The American Conifer Society describes dwarf conifers as plants growing 1 to 6 inches a year, and the even smaller miniature conifers as growing less than an inch a year. Their elfin size may be a result of natural seed mutation, environmental conditions during their evolution or rooted cuttings from witches' broom - tangled, dense, snarled clumps of branchlets that grow on full-sized trees. Yet others may be the handiwork of the cultivators grafting a normal growing species onto a dwarf rootstock, slowing down the growth of the conifer and creating a new dwarf cultivar.
The increasing popularity and availability of dwarf and miniature conifers has grown dramatically in recent years, providing gardeners with fantastic selections of four-season palette color, shape and texture. You'll find plants in every shade of green, unexpected blues to shades of near purple, shimmering silvers, gleaming yellows and golds and variegated combinations. New spring growth may sport lighter and brighter shades while winter foliage can take on hues of red, copper or bronze. Their cones and seed-bearing fruit add yet another dimension to their visual appeal and are useful to wildlife, especially birds by providing shelter and seeds. The plants may be ball-shaped, weeping and pendulous, ground-hugging and carpetlike, or narrow and upright, varying from pencil-thin pillar shapes to columns and slim conical or pyramid shapes. Textures may be fine to coarse and anything in between.
Dwarf conifers make great foundation plants, accent plants, add interest to flower beds, rock gardens, trough gardens and containers. They mix well with a broad range of companion plants from roses to grasses, succulents to perennials.
Generally not fussy plants, they do best planted in full sun and well- draining soil high in organic matter, regular watering during the dry part of the year, and the sparing use of fertilizer.
This time of year you'll see the common Alberta spruce, Picea glauca 'Conica,' in itty-bitty pots. While considered a dwarf, it can reach nearly ten feet tall, while relative, Picea glauca 'Jean's Dilly,' is much smaller, denser and slower growing (four feet in twenty years). If you're looking for a tinge of stunning blue, consider Picea pungens 'Sester Dwarf,' the perfect small form of Colorado blue spruce, only one-fourth the size of its larger parent. In the blue-green range, the long, soft needles of the southwest white pine, Pinus strobiformis 'Coronado,' give a full, fluffy look to this rounded classic beauty.
A favorite of mine, commonly called Hinoki cypress, is Chamaecyparis obtusa 'Nana Gracilis,' adorned with luxurious dense, forest green bunches of shell-shaped foliage on a globelike bush. The golden relative, Chamaecyparis obtusa 'Nana Lutea' displays dense, golden sprays of foliage. And if you like delicate threads of sunny gold, Chamaecyparis pisifera 'Golden Mops' shines in the garden all year on a mounding one- to two-foot-tall plant.
Bright white new growth on Tsuga canadensis 'Moon Frost' nearly glows on a moonlit night, and in winter, it's blushed with pink. If you like Deodar cedars, the striking Cedrus deodora 'Feeling Blue' is covered with soft, gray-blue needles on a gracefully weeping plant that may reach 3 feet tall in ten years.
So, after you pack away the holiday season, keep the sensory pleasures of conifers in mind. Whether you have lots of gardening space, or a postage-stamp lot, you can find space for a few dwarf conifers.
The University of California Marin Master Gardeners are sponsored by UC Cooperative Extension. For questions about gardening, plant pests or diseases, call 499-4204 from 9 a.m. to noon, and 1 to 4 p.m. weekdays, or bring in samples or pictures to 1682 Novato Blvd., Suite 150B, Novato.