What Plant Tissue and Soil Sampling Is Telling Us This Season
- absoluteagronomyne
- Jun 5
- 4 min read
Here’s what we looked at, what it told us, and how that shapes our product recommendations
When we pulled plant tissue and soil samples the week of May 15, we weren’t just after data — we were looking for direction.
It’s easy to get caught up in a wall of data, but what really matters is this:
What’s actually making it into the plant?
What’s just sitting in the soil?
And where can we step in to help close the gap?
That’s where tissue and water-soluble testing comes in. By comparing what’s available in the soil to what the plant is actually taking up, we can make in-season adjustments that protect yield and help you get the most out of every pass.
Why Pair Tissue and Soil Sampling?
Standard soil samples tell us what’s present in the soil. Tissue tests show what’s in the plant. But neither tells the full story on its own.
Water-soluble testing bridges the gap, helping us answer questions like:
Is the crop getting what it needs when it needs it?
Are nutrient levels trending the right direction — or starting to slip?
Is there a better form or timing that would improve uptake?
This side-by-side approach helps us spot issues early and respond with the right product, rate, and placement.
Field-by-Field Observations
Field A
Observations:
Tissue Nitrogen: 3.65% (Low–Deficient)
Tissue Potassium: 2.10% (Deficient)
Water-Soluble P & K: 5 ppm P, 52 ppm K
Ammonium N: 5 ppm
Interpretation:
Nitrogen and potassium uptake are both under target — likely due to weather, root development, or nutrient form. It's also worth remembering that the reported N level reflects just the top 8" of the soil profile. Depending on application method, there may be more N present deeper in the profile.
Organic matter also plays a big role here — for every 1% OM, there’s roughly 1,000 lbs of nitrogen stored in the soil. That nitrogen just needs biology to break it down into plant-available form.
Next Step:
A smart move would be to include a product like Power Pass in the post-emerge herbicide pass to keep metabolism moving and reduce crop stress. If UAN is in play, adding a biological like Phase II can help convert and stabilize that nitrogen investment until it’s taken up by the plant.
Field B
Observations:
Tissue Phosphorus: 0.25% (Deficient)
Tissue Manganese: 61 ppm (Deficient)
Water-Soluble Mn: 7 ppm
Ammonium N: 27 ppm
Interpretation:
Micronutrients like manganese are present in the soil but not getting into the plant — likely a timing or uptake issue. The demand is there, but the delivery isn't lining up.
Next Step:
Including Gainz in the post-emerge application will support micronutrient uptake and help drive tissue levels in the right direction quickly.
Field C
Observations:
Tissue P, Mn, Zn: All tested deficient
Water-Soluble P: 3 ppm
Ammonium N: 52 ppm
Interpretation:
This field is short on both availability and uptake— confirming a true shortage, not just poor timing. When both tissue and soil samples agree, it’s a strong signal to act fast.
Next Step:
We’d recommend running Power Phos alongside Power Pass in the post application. That’s especially important during the V4–V6 window when you’re determining the number of rows around on your corn crops. Gainz would also be a good fit here for addressing low zinc, magnesium, and boron levels.
Field D
Observations:
Tissue Nitrogen: 3.60% (Low–Deficient)
Soil K: 294 ppm
Water-Soluble K: 38 ppm
Ammonium N: 8 ppm
Interpretation:
Nitrogen is trailing behind despite relatively good cation levels. With lower organic matter in this field, there's less free N available — meaning applied N needs to do more of the heavy lifting.
Next Step:
A top-dress N pass would make sense here — whether liquid or dry depends on the operation. We’d also recommend adding phosphorus to that pass: either Power Phos in liquid form or Power Hog as a dry option, both of which convert into plant-usable forms quickly.
Field E
Observations:
Tissue Phosphorus: 0.26% (Deficient)
Tissue Magnesium: 0.17% (Low)
Soil Mg: 425 ppm (Very High)
Water-Soluble Mg: 36 ppm
Ammonium N: 7 ppm
Interpretation:
Despite high magnesium in the soil, uptake is low — a clear case of poor root zone availability or nutrient interaction. Excess magnesium also has another downside: for every 1 lb of excess Mg, about 1 lb of nitrogen can be gassed off.
Next Step:
This field will likely need increased N rates to offset that loss. Adding Phase II to help harmonize the biology and keep N in a usable form is a smart move. A phosphorus source should also be part of that pass to address the tissue deficiency and support root development.
What’s Next
Since this initial round, we’ve already completed a second pull on our corn fields and started sampling soybeans. As those results come in, we’ll keep comparing and refining product recommendations.
If you’re interested in sampling your own acres, let’s talk. We’ll help you understand what’s going on beneath the surface — and how to make the most of every acre.
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