When it comes to planning your crop nutrition strategy, we’ve all been trained to think in three letters: N-P-K.
But here’s the truth: relying solely on nitrogen, phosphorus, and potassium is like building a team and ignoring half your players. Micronutrients may only be needed in small amounts, but their impact on plant health, crop performance, and nutrient efficiency is anything but minor.
So, what are we missing?
Micronutrients like zinc, boron, copper, and iron play critical roles in plant development, enzyme function, and nutrient transport. When even one is low or unavailable, it can limit the uptake of other nutrients, even when your NPK levels are perfectly dialed in.
That’s where the real value of comprehensive soil testing shines: it tells you not just what’s missing, but what might be interfering.
Let’s Talk About Mulder’s Chart
If you haven’t looked at Mulder’s Chart in a while (or ever), it’s worth a closer look. It is a powerful tool for visualizing the relationships between nutrients. It highlights both synergistic interactions (where one nutrient boosts the uptake of another) and the antagonistic effects (where excess levels can block absorption.
A few examples that matter in the field:
- High phosphorus can suppress zinc uptake, especially in corn heavy rotations.
- Too much potassium can reduce uptake of magnesium and calcium, leading to hidden hunger symptoms even when those nutrients are present in the soil.
- Boron improves the uptake of potassium, which is key for fruit and grain development.
- Sulfur helps improve the overall mobility of other micronutrients, like iron and zinc.
What does this mean? Even if your macronutrient numbers look great on a soil test, something as simple as a zinc deficiency (or an oversupply of phosphorus) could be quietly limiting your yield.
That’s the power of understanding nutrient interactions and why a soil test that includes micros gives you the clarity to act before issues show up in the field.
The chart maps out the synergistic and antagonistic relationships between essential plant nutrients. Green arrows show positive interactions, where one nutrient helps the uptake of another. Red lines show negative ones, where excess or imbalance can block absorption.
Boost uptake. Avoid lockouts.
We’re strong believers in synergy over saturation. That’s why we designed Soileos to work with, not against, the soil. Our bioactivated release mechanism ensures nutrients are delivered steadily over time, preventing overloads, reducing antagonism, and improving uptake across the board.
By integrating micronutrients into your crop nutrition plan, you’re doing more than correcting deficiencies, you’re unlocking the full potential of every input.
Why now?
Fall is the perfect time to prepare. A soil test that includes micronutrients gives you the full picture, not just what’s needed, but what’s limiting. That insight can help you make more informed decisions on blends, sources, and application timing heading into next season.
Don’t wait until spring to discover what was missing last year.
Soileos and the 4Rs: A smarter match
Soileos is built around 4R Nutrient Stewardship—Right Source, Right Rate, Right Time, Right Place—because it ensures nutrients stay plant-available longer, interact positively in the soil, and support sustainable crop nutrition. No leaching. No volatility. No antagonism.
Just better results.
Ready to take the next step?
Explore how micronutrient testing can elevate your crop nutrition program
Listen In
Check out our latest podcast 👇
Boost Uptake. Avoid Lockouts.
Start your fall nutrition with Soileos