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Soil is alive! Billions of soil organisms create soil structure that allows air, water, and plant roots into the soil, while recycling nutrients, storing water, and protecting plants from disease. Those organisms live on organic matter such as dead leaves, mulch, and compost.
Dig or rototill compost into the soil before planting.
Mulch is any organic material spread on the surface to conserve water, control weeds, and slowly feed the soil. Different mulches work better for different plants:
Chemical fertilizers can pollute our waterways and damage soil and plant health. The best start for all plants is to amend the soil with compost before planting.
Using too much or the wrong fertilizer damages plants, your soil, and our streams. Call the Garden Hotline to diagnose plant problems, pick the right fertilizer, and to find out how to get an inexpensive soil test that will tell you what’s really in your soil, and what your lawn or garden needs. Free soil testing is available through the King Conservation District.
Compost is available in bags or bulk directly from composting companies and through local nurseries and garden stores. See the Compost Resource List (pdf) or call the Garden Hotline for a supplier near you.
Fall leaves make a great free mulch. Arborist wood chips are often free from tree services. Cedar Grove and other suppliers sell wood chip mulch in bulk, or it’s available in bags at garden stores. The Garden Hotline can help with other mulch ideas and local sources.
Growing Healthy Soil (pdf) – How to select and use compost, mulch, and natural fertilizers.
Get to Know Your Soil (pdf) – Diagnose and solve soil problems.
For more information on building healthy soil and other natural lawn and garden tips, contact the experts at the Garden Hotline at (206) 633-0224 (language interpretation available) or at Garden Hotline.
Soils for Salmon – Construction Best Practices - How to protect and restore soil during construction projects, to help restore wildlife and Puget Sound. Includes links to Seattle’s soil restoration code requirements.
Ecologically Sound Lawn Care Manual (pdf) - Tells professionals (and interested residents) how to amend soil for lawns (page 28 of that (pdf)), and how to improve existing lawns by topdressing with compost (page 35).
RainWise: Managing Stormwater at Home - Learn how to slow and filter runoff with compost-amended soil, trees, rain gardens, cisterns, and other RainWise techniques.