Tech Tuesday: Chemical Indicators

When we talk about soil health, it is easy to focus on the visible. While these physical and biological traits are essential, they only tell two-thirds of the story, for the full picture you need to consider chemical indicators as well. Think of chemical indicators as the “fuel gauge” of the soil. They dictate nutrient availability, the efficiency of your inputs, and the survival of the microscopic life that powers the ecosystem.

The Chemical Building Blocks
Chemicals are not just synthetic additions; they are the fundamental elements that nourish both crops and microbial life. The PES Technologies unit focuses on measuring the primary drivers of plant development:
• pH: The “master variable.”
• Available Nutrients: Phosphorus (P), Potassium (K), and Magnesium (Mg).
• Extractable Nitrogen: Ammonium (NH₄+) and Nitrate (NO₃-)

We focus on available and extractable forms of these chemicals, as only a small percentage of the total amount of the indicator in the soil is available to the plant.

pH: The “Master Variable”
Soil pH is more than a measure of acidity or alkalinity; it acts as the gatekeeper for nutrient uptake. Certain nutrients become more soluble within a certain range of pH. Outside of that range, nutrients can become inaccessible to plants, referred to as nutrient ‘lock-up’. Even if your soil is rich in minerals, a skewed pH can “lock” them away, making them physically inaccessible to the plant. For example, highly acidic soil reduces availability of potassium, and highly alkaline can lock up manganese.

Beyond plant life, pH directly impacts microbial activity. If the environment becomes too extreme, the biological processes that drive nutrient cycling and soil structure will slow down or stop entirely.

The Balance of Inputs
While adding chemicals like Nitrogen is a standard practice to boost yields, more is not always better. Achieving a “chemical balance” is a delicate act: Over-application can lead to soil compaction, nutrient imbalances, and a harmful accumulation of salts. Excessive chemical use can suppress or even kill the beneficial biological life that maintains soil structure. Without testing your pH first, you may be applying expensive fertilizers to a soil that is fundamentally unable to pass those nutrients to the plant.

How do we test it?
Our nutrient testing is done by independent labs, with the results fed into our machine learning algorithm. We use the RB209 scales on our nutrient indicators to enable a smoother soil management decision process.

Conclusion: Test, Don’t Guess
Understanding the chemical makeup of your soil explains why plants might show deficiencies even when nutrient levels in the soil are technically “high.” By integrating chemical data with physical and biological observations, you can move from reactive farming to proactive stewardship.