My tips for developing regenerative systems
In my final column (for now!), I’d like to share my opinions on how we can reduce our reliance on chemical agriculture. These seven practices have helped my clients move toward more disease-resistant and profitable systems.
1. Ca:Mg Ratio
My first step may sound obvious, but I feel it’s often overlooked: the Ca:Mg ratio. In our high-magnesium soils here in California, lack of air exchange is a huge problem. As we get these ratios in line, water movement through the profile improves and the soil can oxygenate much more quickly after irrigation. I’ve seen disease set in on saturated soils, especially when temperatures are elevated and root respiration is in high demand. We also see higher humidity in these environments, enhancing fungal growth.
Like I’ve mentioned in an earlier article, in heavy soils, a 7:1 ratio is desired. In the Sacramento Valley, we are lucky to see a 2:1 Ca:Mg ratio. If you can move it to a 3:1 ratio, you will see immense improvement in creating a more disease-suppressive soil. In lighter soils, a 3:1 or 4:1 ratio is sufficient. To create less reliance on chemical treatments, you must get your soil to breathe. Another benefit of a proper Ca:Mg ratio is that you will see your biology thrive and your pH will line up much faster.
2. Focus on Excesses
Second, you have to get rid of your excesses. With proper testing, you can observe nutrient ratios. Most of our deficiencies are caused by antagonisms. Look first at your major cations: calcium, magnesium, potassium, and sodium, along with ammoniacal N. Any excess will antagonize one another. In our situation, with high magnesium, we have limited nitrogen and potassium uptake. I’ve been able to overcome the high Mg by using injectable solution-grade calcium products. This saves money and time versus amending the whole soil profile. I still advocate amending your soil profile, but you can only do so much in a small amount of time.
Another group I look at is the major anions — phosphorus, sulfur, chloride, and nitrate nitrogen. I see many advisors in our area promote the application of nitrate nitrogen. Nitrate nitrogen does create a quick vegetative response, but it creates self-induced excesses. Not only does the plant require 10-12 percent of its photosynthetic energy just to convert nitrate nitrogen into amino acids, but nitrate nitrogen also antagonizes the all-important phosphorus and sulfur.
Chloride is also a common problem we must address, regardless of whether you are conventional or in a regenerative system. I have used many different forms of carbon inputs to reduce chloride, including leonardite, humic, fulvic, and biochar formulations. By reducing chloride at the critical time of cell division, you will allow phosphorus to function at full capacity, thus giving you better fruit, vegetable, or nut size.
Trace element excesses are also often overlooked. You need the proper ratios for optimum uptake. Iron, manganese, zinc, and copper all interact with each other. I see overapplications of copper that create problems with zinc uptake, along with antagonism with biology (the Zn:Cu ratio should be 2:1 in the soil).
3. Carbon
Third, you’ve got to have carbon, and in a variety of types. Green carbon (freshly cut) has a low C:N ratio and is attractive to bacteria to break it down. Brown carbon has a higher C:N ratio, becoming attractive to fungal species. Here in northern California, rice is a staple, and our high-Mg soils are ideal for holding water in the rice fields. Many growers started removing their rice stubble after burning the straw was restricted. After repeated removal of the rice straw, we started seeing nutrient deficiencies, along with a higher incidence of stem diseases. My opinion is that the lack of available silica was the culprit of the high incidence of disease pressure — rice happens to take up silica in amounts higher than nitrogen, and the rice straw does have high amounts of silica. Most rice growers have shifted their practices by incorporating the rice straw.
Black carbon, such as leonardite, biochar, and oxidized lignite, are great for creating exchange sites for many elements, especially in difficult environments where ratios are out of line. Black carbon is key to buffering salts, thus helping biology thrive.
The photo accompanying this article was taken this past April. The almond orchard on the left is using conventional agriculture inputs; the one on the right has been managed regeneratively. The calcium in these two fields is over 90 percent, creating the iron chlorosis seen on the left. By adding leonardite, we can chelate trace elements, making them available even in these high-pH soils. This is a case where amending the soil will take large amounts to get it corrected. While we are adding some small amounts of amendments, the carbon is allowing us to farm profitably despite the huge imbalances.
4. Reducing Abiotic Stresses
Fourth, use products that help reduce abiotic stresses. Products that I have found very useful are kelp, silica, triacontanol (found in waxy layers of alfalfa leaf), resveratrol (Japanese knotweed), and humic and fulvic acids. By reducing abiotic stress, the plant can prioritize its energy with reproductive growth. I find that combining humic acid with a low-biuret urea in a foliar spray is a very efficient source of nitrogen. Also, humic acid mixed with soil-applied sodium borate chelates it, making it easier to handle and preventing leaching.
5. Trace Elements
Fifth is the addition of the trace elements molybdenum, nickel, and cobalt. Though widely overlooked, they are extremely important for enzyme activity to aid in fixing nitrogen or converting nitrogen to amino acids. I often observe conventionally grown crops that have nitrate nitrogen stuck in the plant — not being converted to an amino acid. Production agriculture’s excessive use of nitrate nitrogen makes molybdenum availability even more important so that this conversion to amino acids can happen. Nickel is required to produce the urease enzyme so that urea can be converted to ammoniacal N. And I find cobalt critical for a thriving biology, but also for nodulation and nitrogen fixing in legumes.
6. Biological Inoculants
Sixth, I use biological inoculants such as compost teas, bacterial inoculant (bugs in a jug), mycorrhiza, and Trichoderma. While nature has innate abilities to heal itself, we have put her in a difficult position with our practices. These inoculants, combined with trace elements, kelp, chitin-based products, and humates, seem to fast-track the process. I’m not saying I put it all in one tank and pray that it works. I use these products individually at first to observe responses, but I’ve starting to learn certain combinations that have great synergism. For instance, combining kelp, humic, and bacterial inoculants works very well. Another pairing I like is cobalt with a chitin-based product. I can’t say one is better than the other — I would have a hard time if I was told I needed to eliminate one. I have also used mycorrhiza lately in my permanent crops to increase the fungal-to-bacteria ratio with great success.
7. Calcium, Boron, and Silica for Disease Resilience
Finally, I highly recommend the trio of calcium, boron, and silica. If you want to create a very disease-resilient plant, this trio is required. All you need to do is read the book “Mineral Nutrition and Plant Disease” and look up these three elements — when levels are good, this trio will not only suppress most diseases but will create an immune response to most attacks. You can’t go wrong with these three, but managing boron is probably the most difficult. Most plants can’t get enough calcium and silica, but boron must be closely monitored in the soil and in the plant.
Even though we have made great advances in understanding the importance of biology, mineral interactions, and carbon’s role in nature, we still have a long way to go. We must not outsmart ourselves and think we are smarter than nature (the green revolution proves that!) — we need to learn from nature before it’s too late.
