Dig This: For Life in the Soil, Consult Grandma’s Thumb


My grandmother was a superb gardener. Her neighbor, Mildred, who knew her well, thought Grandma had some sort of magical powers. But then Mildred got her advice from her cat, so who can know for sure?  One thing is certain, Grandma could grow anything better than anybody. Best tomatoes you have ever tasted.

When I was a child, she enjoyed pulling my leg by sticking her thumb in the garden soil and declaring it ready to plant in — or not. Then she would have me check for myself. Having no idea what I was doing, I always went through the motion of sticking my thumb in the soil just like she did and agreeing with whatever she said.

Grandma understood soil. She knew how a fertile soil feels, smells and tastes, and she knew that in order to keep your soil fertile you needed to put back more than you took out.  She was proud of the fact that she never bought commercial fertilizer, and she grew a LOT of food.

She believed it is a farmer’s responsibility to the commons to improve soil fertility, and that is a metaphor we would all do well to ponder, whether you garden or not. It is neither sustainable nor ethical — it is, in fact, foolish — to consume more than we invest, giving small thought to the future. It is not good for health, business, bank accounts, relationships, forests, the Earth, or anything else we would wish to sustain.

Soil fertility is not just about the presence of available nutrients that plants need to grow. True and sustainable fertility is about vitality. Life. Aside from food safety (no poisons) the most important thing about organic agriculture concerns the life in the soil from which our food derives the building blocks of nutrition and flavor. The life it passes to us.

There is a far more important substance in rich organic soils than the mineral elements which enable soil to hold vitality. It is called humus. To test for that you need Grandma’s thumb.

Just kidding.

The humus content of a soil provides steady fertility and supports the microbial life upon which nutrient transfer to plant roots depends. There is a greater number of micro-organisms in a handful of humus-rich soil than there are humans on the Earth. Eliminate the population of soil creatures and the soil dies.

Mother Nature makes the finest humus around, but very slowly. It normally takes her about a zillion and a half years to make enough soil to fill a clay pot. Since so few of us have that much time, it is good to know that we can make our own soil far more quickly. In just a few weeks time, we can make organic waste materials into compost, which we then feed to our soil where it becomes humus. Super soil.

There are lots of materials available to help nature build humus — from rock dusts to kelp meal — but the only thing you really need is compost. Compost is far better than any organic fertilizer you can buy to enrich your soil. And you can make better compost less expensively than you can buy it.

Making compost is both simple and fun. There are many different ways to make compost and many materials to make it with. I would advise visiting a good bookstore or going online and find a method that suits your needs and capabilities, and use the materials that are readily available where you live.

And as a bonus, by making compost we are also doing our small part to sequester carbon in the soil and contribute to the mitigation of climate change — no small thing these days.

Soil is one of our greatest and most neglected resources. Enriching the soil may be the most sustainable and far-reaching investment anyone can make to the prosperity and health of our nation, or the lives of future generations. It could easily be argued that a nation’s self-determination is grounded in its ability to produce its own food, and history has many tales to tell of the fate of those who have been unable to do so.

Photographs by Melita Bena

Upcoming workshops at the Teaching Garden:

September 25: Cool Weather Gardening Hands-on Workshop, 10 a.m. to noon

Presenters:  Wayne Kessler and Jim Collins 
Community Teaching Garden, Shasta College Main Campus

For registration information, call 530-225-4835


Jim Collins is a local ecopsychologist, organic farmer and founder of a regional seed bank. He is currently garden manager of the Community Teaching Garden project at Shasta College. A pioneer program promoting self-reliance, sustainable practices, regional food security and ecological literacy, the Teaching Garden provides information, instruction, and practical experience in sustainable organic food gardening.

Wayne Kessler is a local organic farmer, nurseryman and activist for local food security. He is the owner of Shambani Organics nursery in Manton with his wife Laurie. Wayne is a technical advisor to the Community Teaching Garden.

Dig This is a regular biweekly column offering ecological wisdom and garden advice. If you have questions or would like Jim and Wayne to address a particular issue, you may contact them at the Teaching Garden by e-mail at teachinggarden@shastacollege.edu.

A News Cafe, founded in Shasta County by Redding, CA journalist Doni Greenberg, is the place for people craving local Northern California news, commentary, food, arts and entertainment.

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