What makes the lowland Puget Sound area distinctive?
|
Seattle, in winter, has many a cold, wet, dark day --such weather as drives natives to testiness and Californians to despair. Well, perk-up! Do you realize that most of North America endures serious freezing right now? Our Seattle winters are relatively mild, but the price we pay is exasperating cloudiness and rainfall. For weeks on end the sun can be a mere memory. From a psychiatrist's perspective, it helps explain our high depression and suicide rates. From a gardener's viewpoint, we are blessed by an ability to expand our range of plants, be they edible or ornamental, far beyond what can grow in severe-winter regions. Hence, my garden has flourishing plants from Mexico, Brazil, Tasmania, New Zealand, South Africa, etc. --virtually all of which would freeze to death in Spokane. Seattle has a truly rare gardening scene, and for the sake of newcomers, here are its highlights.
|
GEOGRAPHIC AND CLIMATIC FACTORS:
|
From about 13,500 to 15,000 years ago, the Vashon Glacier carved the landscape, dug Lake Washington and Puget Sound, while depositing gravelly "till" soil. |
The Pacific Ocean, Puget Sound, and Lake Washington all serve to moderate the temperature and affect the precipitation. The Olympic and Cascade Mountains affect the precipitation. |
No region in the U.S., except Alaska, gets fewer heat units. The Puget Sound's cloudy, temperate conditions and level of rain are ideal for coniferous forests. For 229 out of 365 days it is overcast, and for the latitude, remarkably warm in winter and cool in summer. The low humidity during periods of hot weather is also unusual, and a blessing. Annual rainfall in Seattle averages some 32 to 37 inches. Sea-Tac averages 39 inches, Bellingham 33 inches, and Olympia 52 inches. |
Seattle's average annual temperature is about 53°F (11.7°C).
|
THE SCENE FOR GARDENERS:
|
The summers are bone dry compared to those "Back East," so gardeners must either "go native" or water. Yet the lack of summer heat makes it difficult to grow heat-needing plants such as okra, pomegranates or eggplant. The winters are sopping wet, yet mild; winter vegetable growing is easy (if plants don't drown). The soils are usually poor, infertile gravelly till or blue clay, and need enriching with compost or manure. |
The exact microclimate in any given garden depends on such factors as its elevation, exposure to sun, proximity to bodies of water, degree of slope, existing plant cover, nature of soil, presence of buildings and concrete. Generally, if one lives north or east of Seattle it is colder and more rainy, if one lives west or south, it may be drier, may be warmer, but varies a great deal. |
Likely no other area in North America has so much to offer by way of garden clubs, programs, libraries, tours, classes, excellent nurseries, and other opportunities. Talk about uneven allocation of resources! Horticulturally, Seattle has boomed recently --in the last 30 years all of the following came about:
|
- Bellevue Botanic Garden |
- Cedar Grove Compost / Clean Green program |
- Center for Urban Horticulture |
- Community College Horticulture classes |
- Flora & Fauna Bookstore |
- Food composting with worms |
- Green Gardening program |
- Master Gardeners |
- Northwest Flower & Garden Show |
- Northwest Gardener's Resource Directory by Stephanie Feeney |
- Northwest Horticultural Foundation |
- P Patches |
- PlantAmnesty |
- Seattle Tilth Association |
- Washington Big Tree program
|
(Originally written in November 1995 for a Seattle Tilth lecture; rewritten for a January 1996 Montlake Flyer; rewritten in part for the introduction (page 10) to the book Wild Plants of Greater Seattle. And the version above is yet more rewritten.)
Back |