Until now, my answer to creating good dirt has been this: Make it mooly. I explain, using a good Scottish word, that good growing soil needs to be soft and crumbles easily, but retains enough body to hold moisture. I tell them creating mooly garden soil takes years of painstaking work – troweling, shoveling, hoeing, raking – in short, tilling one’s arse off.After years of watching me putter in the garden, my grown sons have taken to the soil, planting, like most men, vegetables.
They turn up their trowels at the mention of flowers, like most men, and ask about good soil and practical results. Although I love flowers, I indulge their interest in efficiently producing food. They want to know, like most men, how to create the best growing medium with the least amount of effort.
In commercial agricultural fields, it also takes years of tilling to get mooly soil using heavy equipment and field crews. But mooly soil is only part of the equation. Plants need water, an ingredient that has been in extremely short supply in California lately, this year being an epic drought. It has been so dry here that the wooden door frames in my house have shrunk and doors are out of true and don’t properly latch anymore.
So I got excited the other day when I learned a company in Virginia has found a way to grow and sustain vegetables, fruits and flowering plants using nothing more than gravel, sand and cotton based fabric. They say using gravel to grow crops is the most efficient method in history.
I’ll grant them the over-statement, ignoring the dry-land growing techniques used since the beginning of time and all the research and successful demonstrations of deficit crop irrigation. And that’s not to mention the ancient art of bonsai, the sculpting of miniature trees grown in crushed rock, with bits of organic matter. See a feature story on “Bonsai: Shaping Nature’s Narrative,” explaining how these living artworks thrive in a growing medium of crushed rock and bits of bark.
But, experts are calling geological agriculture is a new science defined as the study of using rocks to grow crops without soil and fertilizer. Commonly known as gravel gardening, they say this form of crop cultivation will bring significant sustainable agriculture benefits to populations around the world, predicting that a variety of industries will find value from gravel gardening, including home and community gardeners, real estate developers, commercial farmers, landscapers, restaurant owners, health care providers and international development organizations.
Promoted by To Soil Less, a family business founded in 2010, owner Richard Campbell (no relation) shares the growing body of information on gravel-based growing techniques and practices with the agriculture and gardening communities. Download a free how-to guide from the company’s website.
Professor Arvazena Clardy Ph.D., Assistant Professor of Horticulture at Tennessee State University, has been researching the practicality of gravel gardening and calls Campbell’s techniques a “significant step for plant sciences.” She and 39 TSU agriculture students conducted a germination study of various crops using river pea gravel as the growing medium.
Their research conclusions can be found in Campbell’s guide Grown in Gravel: The Sturiculture, available online from Amazon and at participating Ace Hardware locations. Combined, he says these studies begin to shape the academic building blocks of this new science.
The book includes a 16-page gravel gardening gallery of the past year, along with the first geological agriculture glossary of terms, which introduces a variety of new terms to describe the process of rock-based crop production.
Campbell says gravel gardening benefits include:
1. No soil needed.
2. Less Watering.
3. No fertilizers.
4. Less Weeding.
5. Less Cost.
7. Efficient Irrigation System.
In the meantime, for sustainable gardening ideas using drought tolerant plants and native soils, check out the Poetic Plantings website. Marianne Simon founded the Southern California landscape design company, Poetic Plantings, with the vision of creating gardens that nurture the spirit and the earth. Many of her designs use native soils, rather than top soils and potting mixes. Take a look at her online portfolio of completed garden.