If you want to grow healthy plants, you need to build healthy soil.
Healthy soil is full of nutrients, microorganisms and organic matter. It has good drainage and water holding capacity and helps keep the water and air free of pollutants. Improve the quality of your soil by adding compost and mulch. Before you add fertilizer, test your soil to find out what your garden needs and make sure the soil is free of contaminants. You can build healthy soil by planting cover crops, using a “no-till” technique such as sheet mulching or straw bale gardening, and rotating your crops to prevent attacks from pests and disease.
Soil Testing
King Conservation District Soil Testing Program
Tests for fertility, pH, and organic matter. Does not include testing for heavy metals.
Free testing for landowners who reside within the eligibility area, one time only, five samples.
Additional soil tests can be added for a fee.
www.kingcd.org, soiltesting@kingcd.org (425) 282-1905 or (425) 282-1900
UMass Extension Soil & Plant Tissue Testing Laboratory, Amherst, MA
Tests for fertility, pH, cation exchange, lead and aluminum. Extra charges for organic matter and soluble salts.
soiltest.umass.edu, soiltest@umass.edu (413) 545-2311
Cascade Analytical, Inc
Tests for fertility, organic matter, pH, and soluble salts. Extra charges for lead and arsenic.
www.cascadeanalytical.com/analytical-services/agricultural/soil-fertility (800) 545-4206
Soiltest Farm Consultants, Inc.
Offers a variety of tests for fertility, heavy metals and other elements.
www.soiltestlab.com (800) 765-1622 or Local (509) 765-1622
Kuo Testing Labs, Inc.
Offers a variety of tests for fertility, heavy metals and other elements.
www.kuotestinglabs.com Toll Free (800) 328-0112 or Local (509) 488- 0112
Edge Analytical Laboratories
Tests for heavy metals, bacteria, pesticides and other contaminants.
www.edgeanalytical.com (800) 755-9295
Sheet Mulching and Straw Bale Gardening
Find local sources of arborist chips, organic straw bales, cardboard or burlap bags:
Chipdrop, free chips from local arborists – sign up service
The Garden Hotline, gardenhotline.org (206) 633-0224, help@gardenhotline.org
Cover Crops
Mail Order:
Fedco Seed Company, (207) 426-9900
Johnny’s Selected Seeds, (877) 564-6697
Osborn Seed Company, (360) 424- 7333 Canadian rep (607) 518- 6953
Peaceful Valley Farm Supply, (888) 784-1722
Territorial Seed Company, (800) 626-0866
Local Retail – King County:
Bellevue Nursery, (425) 454-5531
McLendon’s Hardware, Renton (425) 235-3555 Woodinville (425) 485-1363
Molbak’s Nursery, (425) 483-5000
The Grange in Issaquah, (425) 392-6469
Local Retail: Seattle:
City People’s Garden Store, (206) 324-0737
Magnolia Garden Center, (206) 284-1161
Sky Nursery, (206) 546-4851
Swansons Nursery, (206) 782-2543
Walt’s Organic Fertilizer Co., (206) 297-9092
West Seattle Nursery, (206) 935-9276
Certified Organic Soil Products
Bulk
Bailey Compost, (360) 568-8826
Cedar Grove Composting, (877) 764-5748
DirtExchange, (206) 599-3478 (carries Cedar Grove products)
Sky Nursery, (206) 546-4851 (carries Cedar Grove products)
Yelm Earthworm & Castings Farm, (877) 339-6767
Bagged
Black Gold OMRI certified products – available at local retail stores including Fred Meyer
Cedar Grove Compost & Potting Soil – available at local retail stores
Zoo Doo compost. Call the ZooStore at (206) 548-1535 to check for availability.
Organic Fertilizer Sources
Walt’s Organic Fertilizer Co., (206) 297-9092. Granular certified organic ‘Rainy Pacific NW Blend’ fertilizer and others blended for local conditions.
Hendrickus Organics, 425) 392-9977. Granular certified organic fertilizers and soil conditioners blended for local conditions.
Dr. Earth, Granular and liquid fertilizers
E.B. Stone, Granular and liquid fertilizers
Neptune’s Harvest, Granular and liquid fertilizers
WISErganic, All-purpose organic liquid fertilizers made from food scraps collected at PCC Natural Markets and made into fertilizer in Issaquah.
Wiser Worm Farm, Worm tea fertilizer made from certified organic worm castings.
Crop Rotation for Integrated Pest Management and Fertility
“The Maritime Northwest Garden Guide”, Tilth Alliance, rev. ed., 2014.
“Your Farm in the City”, Lisa Taylor, 2011, Black Dog and Leventhal Publishers, Inc.
“Growing Vegetables West of the Cascades”, Steve Solomon, 2007, Sasquatch Books.