All analogies have limits, but the similarities between human health and soil/plant health are striking.
Most obvious is the popularization over the past decade or two of the importance of gut health for people, and the similar growth in recognition of how vital soil microbes are to the health of the soil — as well as microbes on the roots, stalks, leaves, and fruits of plants.
There’s something very enticing about the idea of optimizing plant nutrition. To be able to know, with some degree of precision, what a plant is lacking — or overabundant in — and to be able to course-correct mid-season is a powerful idea. Especially exciting is how that ability to be precise is improving with advancements in technology.
For several decades, all we had was plant tissue analysis. It can be a useful tool, but many have found that it doesn’t perfectly correlate to what a soil test is saying, nor what the grower can observe is actually happening with the plant. Now sap analysis is available — a technology that is more precise and useful to growers. There’s really no reason every professional grower shouldn’t be using sap testing. You can’t manage what you can’t measure, and sap testing is the most powerful tool on the market today for measuring plant needs.
Other testing solutions are on the horizon, and many will enable growers to test their soil and their plant right in the field, without having to send samples to a laboratory. These include x-ray fluorescence (discussed in this magazine in an interview with Jill Clapperton in August 2022) to soil biology testing via a phone app (MicroBiometer — see the article by the late Judith Fitzpatrick from April 2022) and compost DNA testing (to be discussed in a future issue by Dr. Laura Kavanaugh).
And, of course, the other half of Moore’s law is that the price of the improved technology goes down over time. Sap analysis is very affordable for a commercial grower right now, but in coming years it will surely become even more accessible — perhaps even to home gardeners.
But we shouldn’t forget that in addition to these technologies for plant nutrition diagnosis, we also have a time-tested, low-tech option: visual observation. This takes training and practice and wisdom, but it shouldn’t be forgotten. To riff on Dr. Albrecht — test your plants, and observe them in the field; and when they disagree, trust your in-field observations. This idea has limits — there’s lots the human senses can’t observe about how a plant is doing (including the ultrasonic sounds they make when stressed, as highlighted in last month’s Eco-Update section). But it’s a good general principle.
In this issue of Acres U.S.A., agronomist Gary Reding explains how proper plant nutrition can lead to increased plant resiliency, quality, and yields — as opposed to the techniques that advocate intentionally stressing plants by depriving them of water or nutrients in order to try to increase potency. Gary Zimmer — who will host a learning experience and tour of his farm this August 15-16 (events.acresusa.com) — discusses how soil health management is a farm management decision. And — this being July — Tim Johnson provides some tips on helping plants survive the summer heat.
And that’s the view from the country.
