Unlock Better Crop Coverage
Urgent Need for Precision
New EU rules ban 12 pesticide co-formulants, requiring urgent reformulation or withdrawal
This directly impacts how your sprays perform, making accurate calculations crucial.
The Surfactant Solution
Without specific co-formulants, many existing crop protection products will struggle to sp
Accurate surfactant adjuvant calculations ensure your valuable sprays work as intended.
What is a surfactant adjuvant and why is it used
Surfactant adjuvants are substances added to spray mixtures to improve the efficacy of cro
They reduce the surface tension of water, allowing spray droplets to spread more evenly ov
Why use them in farming?
Surfactants ensure pesticides, herbicides, and fertilisers stick and penetrate better.
This is especially true on waxy or hairy leaves, where sprays often bead up and roll off.
How do surfactants help pesticides stick to waxy
Waxy leaves naturally repel water, causing spray droplets to form beads and roll off befor
Surfactants break this surface tension, allowing the liquid to flatten out and cover more
The science explained
Surfactant molecules have both water-attracting (hydrophilic) and water-repelling (hydroph
They orient themselves at the water-air-leaf interface, effectively 'wetting' the leaf sur
What is the recommended percentage rate for agri
The recommended rate is typically given as a percentage volume per volume (% v/v) on the p
This rate varies significantly by product, crop, and the specific pesticide being used.
Common percentage range
A common range might be between 0.05% and 0.5% v/v, but some products could recommend high
Using too little may render the spray ineffective; too much can cause phytotoxicity or exc
The Calculation Challenge
Converting a percentage rate into an exact volume for your spray tank can be tricky withou
Miscalculations lead to wasted product, poor results, and potential crop damage.
How do I calculate the correct surfactant amount
First, identify your spray tank volume (e.g., 500 litres) and the recommended surfactant r
Let's use these common, simple figures for our illustrative example.
How to calculate (Step 2)
Convert the percentage rate into a decimal. For 0.1% v/v, divide 0.1 by 100, which equals
This decimal represents the fraction of the tank volume that should be surfactant.
How to calculate (Step 3)
Multiply your tank volume by this decimal. So, 500 litres * 0.001 = 0.5 litres.
This means you need 0.5 litres of surfactant per 500-litre tank.
How to calculate (Step 4)
For easier measurement, convert litres to millilitres. 0.5 litres * 1000 mL/litre = 500 mL
So, for a 500-litre tank at 0.1% v/v, you add 500 mL of surfactant.
What about total volume?
Now, imagine you need to spray a total area requiring 5,000 litres of spray mixture.
Your 500-litre tank will need to be filled multiple times to cover this larger area.
Number of tanks needed
Divide the total spray volume by your tank size: 5,000 litres / 500 litres/tank = 10 tanks
You will need to fill your sprayer 10 times to cover the entire area effectively.
Total surfactant required
Multiply the surfactant needed per tank by the number of tanks: 500 mL/tank * 10 tanks = 5
This equals 5 litres of surfactant in total for the entire spraying job.
What are the benefits of using a surfactant in c
Surfactants improve spray coverage and adhesion, leading to better uptake of active ingred
This maximises the effectiveness of expensive pesticides and fertilisers.
More benefits
Reduced runoff and evaporation mean less product waste and a more environmentally responsi
Ultimately, this translates to healthier crops, higher yields, and better financial return
Can I use household detergents as a crop spray s
No, household detergents are not suitable for agricultural use. They are formulated differ
They often contain perfumes, dyes, and other additives that can be toxic to plants or caus
Why not use them?
Agricultural surfactants are specifically designed, tested, and regulated for plant safety
Always use products clearly labelled for agricultural adjuvant use to protect your crops a
Pro Tip: Read Labels
Always read the product label for both the pesticide and the surfactant adjuvant. They con
Pay close attention to mixing order, water volume, and any specific compatibility notes.
Pro Tip: Water Quality
Water quality (pH, hardness) can impact surfactant performance. Test your water and adjust
Some surfactants work best within a specific pH range, influencing spray efficacy.
Calculate with Confidence!
Stop guessing your surfactant amounts. Use our free online calculator for instant, accurat
Try the Free Calculator
Enter your spray volume, tank size, and % v/v rate. Get your surfactant per tank, total mL