Simple and Successful Market Gardening

A few weeks ago, I was a mentor for the Market Gardener Institute’s CANOPY leadership program, an intensive workshop for 25 emerging leaders in agriculture. I gave a seminar to the attendees on nutrition management in market gardens. I’ll be distilling some of that information in a series of blog posts here over the coming weeks.

Many growers are interested in implementing regenerative practices at a small scale or with a broad diversity of crop types. In these cases, the standard tools we rely upon at AEA, like sap analysis and targeted foliar sprays, are not practical management options, either because of cost, scale, or complexity. There is still a whole lot you can do without these management techniques, by focusing on some simple principles.

The simplicity on the other side of complexity

On the surface, the following principles seem very simple. But their simplicity is only possible because they are founded on a tremendous amount of scientific research, grower experience, and understanding the intricacies of plant physiology. They are the simplicity on the other side of complexity.

The simplification of fertility management is based on the Pareto Principle: the idea that 80% of effects come from 20% of the actions taken. So the question is: what 20% of the actions are the most important ones, the ones that cause the vast majority of effects in our farm biology and fertility? And therefore what are the 20% of actions that we as farm managers need to focus our energy on?

The goal of managing nutrition in regenerative market gardens should be to make our program as simple as possible, but no simpler! I have simplified the process down to six essential steps. But none of these steps can be skipped–if you skip any step, you won’t get nearly the same results. The six steps are:

1. Create the right physical environment
2. Add biology that has been lost
3. Feed biology with mulch or cover crops
4. Provide balanced mineral nutrition
5. Use foliar nutrition to speed up the system
6. Avoid excess nutrients

I’ll devote an entire post to each of these steps, but for now I will explain some of the foundational principles behind them.

Biology Supersedes Chemistry

The fundamental principle behind each of these steps is that your farm will only be successful when plants get most of their nutrition from biology. When it comes to plant nutrition, biology supersedes chemistry. Think of it like this: perfect chemistry with poor biology will fail. But imperfect chemistry with good biology will succeed. All six of the steps help create a soil system with thriving biology, which can provide all of a plant’s nutrient needs through the complex metabolites they produce, as well as through rhizophagy.

Rhizophagy

The rhizophagy cycle is the process in which plants absorb living microbes through their root tips–basically swallowing bacterial cells whole. The plant then strips the membranes off the bacterial cells. Some of these bacterial cells are basically “eaten” through endocytosis, and are fully absorbed by the plant’s cells. Others are re-emitted by the plant through its root hairs. These microbes become “messengers,” advertising the plant’s nutritional needs throughout the soil microbiome. The plants farm the microbiome in much the same way that we farm livestock.

Essentially plant digestive systems are similar to our own, or to the rumens of ruminant mammals–they are driven by the microbiome contained within.

The discovery of the rhizophagy cycle is a really big deal. It means that plants do not derive their nutrition from simple ions, as the mainstream chemical approach to agriculture has presupposed, but that they rely on whole microbes for a substantial part of their nutrition.

Rhizophagy has been studied extensively by Dr. James White of Rutgers University, who I interviewed on the Regenerative Agriculture podcast. I’d recommend listening to that episode to learn more.

In the next post, I describe the steps needed to create the right physical environment for microbes to thrive.