Mar 2, 2021

We need to talk about the soil

{Sponsored} Spare a thought for your soils this season. We expect a lot of them, but so too do modern agricultural practices, says Dean Konieczka, consultant agronomist with OMEX® Agrifluids.

Is there a ‘good’ soil for fruit? Well, it depends what type of fruit, but in general, a rich, moisture-retentive but well-drained soil will have your fruit thanking you. In practice, that means a soil with a sandy, loamy nature: easing planting, agronomic operations and harvesting.

We don’t do enough to look after our soils. Applications of plant protection products, fertilizers and the effects of heavy machinery, at often less-than-perfect timing, all take their toll. Then we still expect them to deliver strong, high-yielding healthy crops.

Truth is, like a rock star at a concert, these ‘made for fruit’ soils demand careful management to see them perform to their full potential.

Cultivation and chemical activity can leave the soil unable to support uniform plant growth, both vegetative (leaves and stalks) and reproductive (flowers and fruits). It’s under these intense conditions that organic matter, what we call ‘sustainable carbon’, can be lost from the soil. Without a minimum level of organic matter, there won’t be enough microbe activity to adequately colonize the crop’s root zone.

These microbes aren’t a ‘nice to have’, but essential. Without them, applied fertilizers become largely ineffective: plants rely on microbial activity for nutrient absorption, uptake and utilization.

It’s often said we don’t fully understand the soil on which we stand. It’s easy to see why. A single teaspoon of ‘average’ soil contains about one billion bacteria, yards of fungal filaments, thousands of protozoa and scores of nematodes — each playing its role in the soil merry-go-round.

Some of those players — certain nematodes, for example — aren’t welcome, but plenty more are essential for healthy crops.

Rhizobium bacteria fix nitrogen from the atmosphere — a staggering 70 million tons a year. Various fungi — mycorrhizae — form partnerships with plant roots, refining absorption of soil nutrients. Both rhizobium and mycorrhizae produce polysaccharides and nutrient salt complexes, substances that bind soil particles into larger aggregates, improving water retention and preventing soil erosion.

Protozoa, meanwhile, constitute an important link within the soil food chain, consuming bacteria and producing as much as 80 percent of the soil nitrogen that eventually ends up in plants, while themselves a food source for invertebrates.

Then there’s earthworms: mixing up soil, deep-diving with surface organic matter to stimulate bacteria and increase water retention.

It’s easy to see the fragility of this complex web; even basic forms of agriculture affect the equilibrium of soil health. Although we’ll never farm without modifying this soil jungle, remedial action can be taken.

Enter organic acids. These aren’t acids in the broader sense — they won’t dissolve anything, nor acidify the soil — but weak chemical acids from decomposition of organic matter. Research shows their crucial roles in mineralization and solubilization, while contributing to the carbon cycle, detoxification of metals and, importantly, uptake of applied nitrogen and nutrient complexes like DAP and MAP.

Organic acids comprise a variety of biological compounds, produced from biotic and abiotic soil processes. ‘Humic acid’, insoluble in water, is instrumental in soil binding. Water-soluble ‘fulvic acid’ acts both as nutrient facilitator and ‘chelator’ — binding nutrients like phosphorus, calcium and iron — that would otherwise bind together, inaccessible to the plant.

Common to both compounds, alongside another called humin, is that we still don’t fully understand them! Observations in soil research — such as those conducted by the universities of Ohio State and North Carolina — have shown how even small doses of humic acids increase plant growth and root mass, but the chemistry and function itself remains the subject of much debate.

It’s this lack of understanding, the inability to explain fully how these substances work, that has often left them on the periphery of crop nutrition. And because they’re naturally occurring substances, which can’t be protected by patents, there’s little incentive beyond the research community to conduct studies to encourage commercial use. Vitamin D in human health is a good parallel; we know it can help protect us against respiratory disease, but we don’t know why or how, and no drug company will fund such research without prospect of a return on investment.

Despite these issues, OMEX® has stuck — perhaps stubbornly — with organic acids. We recognize that when growers use products such as Cell Power® SLYCE® and our other formulations, not only do they produce a result but an evidently valuable result, especially for soils low in organic matter. Typically, we see the effect of SLYCE® in vigor: good shoot and root development. But it also promotes chlorophyll development and improves potassium transport, both of which increase the plant’s ability to cope with stress situations later in the season, such as hot weather and drought.

Developing the proper form, timing and rates to use organic acids through the growing cycle is crop and climate specific. You, or your agronomist, will need to consider factors such as nutrient use, water availability and soil type — and of course, OMEX® is always available to help you get the most from organic acids for the soil beneath your fruit.

Learn more at www.OMEXusa.com.

The product names and brands referenced here are registered and trademarks of OMEX® Agrifluids, Inc.

© OMEX® Agrifluids, Inc. 2021.