Foliar Spray PPM Calculator
Foliar sprays work at much lower PPM than root feeding — and leaf burn from overdoing it is instant and ugly. Enter your sprayer volume and target PPM for a safe mix.
Calculator
Foliar Spray PPM Calculator
Was this calculator helpful?
Your feedback helps us improve the calculator and its explanations. This is CalculatorsPPM user feedback, not a Google review.
Foliar sprays work at much lower PPM than root feeding — and leaf burn from overdoing it is instant and ugly. Enter your sprayer volume and target PPM for a safe mix.
How to use this calculator
- Enter sprayer volume.
- Enter target PPM (often 250–1,000 for foliar).
- Get grams.
- Spray in cool evening hours.
The formula
Grams = target PPM × liters ÷ 1,000 ÷ active fraction.
What the inputs mean
The target is the concentration you want, in PPM. The volume is how much liquid you are treating. The active ingredient (%) corrects for product strength, because most products are not 100% active ingredient. The result tells you exactly how much spray product to add.
Worked example
10 L sprayer, 500 PPM, product 20% active: 500 × 10 ÷ 1,000 ÷ 0.20 = 25 g.
Quick reference
| Sprayer | Grams for 500 PPM (20% product) |
|---|---|
| 5 L | 12.5 g |
| 10 L | 25 g |
| 20 L | 50 g |
Adjust for product strength.
Where you will actually use this
Leaves absorb fast; the margin between feeding and burning is thin.
- Micronutrient correction
- Calcium foliar sprays
- Pest/disease products
Mistakes that give wrong answers
- Spraying in hot sun (burn risk)
- Using root-feeding PPM for foliar
Key takeaways
- Formula: Product (g) = Target PPM × Spray volume (L) ÷ 1,000 ÷ active fraction
- Remember: Adjust for product strength.
- Watch out for: Spraying in hot sun (burn risk)
- Next step: run your own numbers in the calculator above, then verify with a measurement — calculated values are only as good as the inputs.
Frequently asked questions
What PPM for foliar feeding?
Typically 250–1,000 — much lower than root zones.