It's that time of year again. Another year of watering has left your soil badly in need of a boost. According to all the gardening experts, it's the dirt that really matters. So if you do one thing to prep your garden for spring planting this year, we recommend you make rich, nutrient-dense soil. We've dug in and unearthed a few "dirty little secrets" to help you along your way.
The Nitty Gritty
From a relatively dry winter to a fast-approaching spring, 2012 will be the year to add drought-tolerant plants to the garden. Curator Don Mahoney gives some tips for creating optimal soil conditions.
Most drought-tolerant shrubs, including rosemary and lavender, need very well-drained soils to survive. Sometimes planting on a slope is enough, but flat clay soil areas need amending.
- What to do about clay
To improve drainage, the best amendments for clay are pea gravels, road base rock, or medium bark chips added at a ratio of at least one part drainage material to two parts clay soil. Natives like manzanitas, ceanothus and fremontododenrons appreciate being planted on small mounds to six inches high so that excessive water will run away from the crowns.
- Too much sand?
If your soil is too sandy, the best amendments are organic materials such as redwood compost fortified with nitrogen, compost, rotted leaves or needles.
Never add raw wood chips into the soil as their decomposition robs the soil of nitrogen.
Don't add sand to clay, as it can turn into hard-pan.
Organic material decomposes rapidly and needs to be replenished yearly.
Wood chips are a good surface mulch to conserve water and suppress weeds.
Books on Soil
Here's a selection of favorites from Garden Bookstore Manager Dennis Gutmann. To reserve your copies, contact Dennis at (415) 661-1316 ext 408.
Secrets to Great Soil by Elizabeth P. Stell
Teaming with Microbes: The Organic Gardener's Guide to the Soil Food Web by Jeff Lowenfels and Wayne Lewis
Gardening Month by Month in Northern California by Bob Tanem and Don Williamson
Planning Your Vegetable Garden
Master Gardeners of Santa Clara County describe the best location, the most efficient use of space, preparing a garden plan and tools.
Adjust Your Soil Acidity
The East Bay Express reports on East Bay soil and how to test and adjust the pH.
The East Bay Urban Agriculture Alliance lists key points in evaluating your soil.
Norm's nursery, an East Bay blog, emphasizes the importance of soil and recommends a new product.
Gardening for the Environment
A great local resource for urban composting tips, including a Gardening & Composting Educator Training Program.
From the Ground Up
Learn how to identify your soil type and discover backyard composting,
mulching and other soil-building techniques in this free March 10 workshop. Co-sponsored by the Marin Municipal Water District and the Urban Farmer Store.