Herbicide Performance & Spray Stress
When sprays don’t work as expected
Many growers notice that herbicides or foliar sprays don’t always give the results they expect. Weeds persist, crop response is uneven, or chemical performance seems inconsistent.
Spray performance isn’t always about the product — often, it’s influenced by plant and soil health, environmental conditions, and application technique.
Common causes of spray stress
Plant condition
Stressed or nutrient-deficient plants absorb chemicals less efficiently, reducing herbicide effectiveness.
Environmental conditions
Heat, cold, wind, or rain during and after application can reduce uptake and performance.
Soil health and microbial activity
Healthy soils produce stronger, more resilient plants. Plants with well-functioning root systems take up sprays more effectively.
Application factors
Incorrect timing, poor spray coverage, or incompatible products can also limit performance.
How to reduce spray stress
Improving spray outcomes involves supporting the whole system, not just relying on chemicals:
Maintain healthy, nutrient-balanced plants
Improve soil biology to support root function and plant resilience
Apply sprays under optimal environmental conditions
Use products that enhance spray uptake when needed
Where our products fit (practical tools growers use)
Our Weed Spray Enhance product is specifically designed to support spray performance:
Weed Spray Enhance
Helps improve herbicide uptake
Supports plant resilience during spraying
Compatible with most common herbicides
Other products like Lazerhume, Restore, and Optimise iO indirectly support spray performance by improving soil health and plant robustness, ensuring sprays are more effective across the paddock.
When this approach won’t help
Spray performance may remain limited if:
Environmental conditions are extreme (frost, rain, or wind)
The wrong product is used for the target weed
Physical application errors occur (coverage, tank mixing, etc.)
Supporting plant and soil health enhances results but doesn’t replace correct chemical application practices.
Related growing problems
Spray stress is often connected with:
Addressing these underlying issues helps maximise both chemical and natural plant performance.
Frequently asked questions
Can Weed Spray Enhance replace herbicides?
No — it’s designed to improve uptake and effectiveness, not replace chemicals.
When should I use it?
Apply alongside herbicides according to label directions and under suitable environmental conditions.
Will it help stressed plants absorb sprays better?
Yes — it supports plant resilience and improves herbicide absorption for more consistent performance.
Key takeaway
Spray stress often results from plant and soil health issues, not just the herbicide itself. Supporting robust plants, healthy soils, and correct application practices helps chemicals perform more reliably, saving time and resources.
Explore all common growing problems and solutions in our “Growing Problems Hub.”