BY JEFF COX / Kenwood, California, USDA Zone 9
NURSERIES OF NOTE
Sonoma Horticultural Nursery
Amid the host of specialty nurseries in Sonoma County, California, Sonoma Horticultural Nursery stands out for its collection of shade-loving woodies and perennials. Its eight acres of mature gardens are home to 800 varieties of rhododendrons, 500 varieties of azaleas, and much more. The nursery is located at 3970 Azalea Avenue, Sebastopol, CA 95472. For more information, call 707-823-6832 or visit www.sonomahort.com.
Before I moved from Pennsylvania to California, the idea of having a 300-day growing season seemed paradisiacal. I pictured the last of my roses decorating the table at Christmas, daffodils blooming in February, and fresh food from the garden almost year round.
And so it has proved. That’s the good news.
The downside to such a long growing season is the constant need to keep the soil stocked with actively decaying organic matter. You don’t have to be a gardener for very long before you realize that the quality of the soil determines the health and quality of the plants that grow in it. Good-quality soil is dark and crumbly from the humus that’s accumulated in it. Water percolates quickly and plant roots grow easily through it. Spongy humus soaks up water and holds it until plants need it. Humus also holds plant nutrients on its surfaces, releasing them into the soil only as fast as plants deplete them. It’s key stuff in creating a loose, easily worked, nutrient-rich garden soil.
Now consider a tropical soil. There’s very little humus in it. All its nutrients are aloft in the form of trees and other plants, and as animals. As soon as a leaf falls to the ground, decay microorganisms, fungi, insects, and other creatures quickly tear it apart and recycle its nutrients. Clear-cut a tropical forest and the soil soon turns hard and lifeless. Now consider a soil of the northern forest. The forest floor is thick and springy with humusy duff. Sometimes the accumulations of decayed plants are many feet thick. The difference is that in the warm tropics, the digestive processes of soil life are always working, always turning plant remains back into plant nutrients, which are quickly taken back up by the plant life there. In the northern forest, decay only operates when the soil temperatures warm up for just a few summer months. Dead plant matter accumulates faster than the soil life can dismantle it.
Here in California, as in all warm climates—especially wet ones like Florida and the Gulf states—a 300-day-plus growing season means that the soil is digesting organic matter nearly year round. I’ve made raised beds of pure compost that a year later were almost devoid of actively decaying organic matter and its end product, humus.
When I lived in Pennsylvania, gardening ended for me around mid-October and didn’t really start again in earnest until mid-April. That’s six months off. In California, the grand wheel of life spins inexorably from mid-February to mid-December, and I’m running along with it, hauling wheelbarrows full of compost to the insatiable garden in fall, more in spring, and still more in summer. That’s in addition to the effort needed to make all that compost, plus all the rest of the gardening chores. Not that I’m complaining, mind you. H
Botanica North America
by Marjorie Harris (HarperResource, 2003; $59.95)
After reading just a few pages of Botanica North America. I fell in love with it. It is at once intelligent, beautifully written, wildly informative, and vast in scope—its subtitle, “The Illustrated Guide to Our Native Plants, Their Botany, History, and the Way They Have Shaped Our World,” says it all. The informative entries are filled with anecdotes, quotations, poems, and arcane knowledge. It’s expensive, but worth every penny.