Calculator inputs
Example scenarios
| Scenario | Inputs | Example output (approx.) |
|---|---|---|
| Foliar spray | 10 L, target 0.5 ppm, borax 11.3%, 90% efficiency | ~0.49 g product |
| Fertigation | 20 gal, target 1.0 ppm, solubor 20.5%, 85% efficiency | ~1.75 g product |
| Soil application | 100 m², 0.2 g B/m², boric acid 17.5%, 90% efficiency | ~12.70 g product |
Examples are illustrative only; confirm rates and compatibility for your crops.
Formula used
1) Solution / spray mode (ppm in water)
ppm is treated as mg/L. The tool calculates the increase needed above any existing boron.
- Δppm = max(0, target_ppm − existing_ppm)
- Elemental B (mg) = Δppm × volume_L
- Elemental B (g) = Elemental B (mg) ÷ 1000
- Adjusted elemental B (g) = Elemental B (g) ÷ efficiency
- Product (g) = Adjusted elemental B (g) ÷ (percent_B/100)
2) Soil mode (rate per area)
The elemental boron rate is converted to grams per square meter, then multiplied by total area.
- Rate (g/m²) = convert(rate_value, rate_unit)
- Elemental B (g) = Rate (g/m²) × area_m²
- Adjusted elemental B (g) = Elemental B (g) ÷ efficiency
- Product (g) = Adjusted elemental B (g) ÷ (percent_B/100)
How to use this calculator
- Select Application mode: solution/spray or soil application.
- Pick your Borate product (or enter a custom % boron).
- Enter volume + ppm targets (solution) or area + rate (soil).
- Set an Efficiency factor to account for practical losses.
- Click Calculate to see grams and teaspoon estimate.
- Use Download CSV or Download PDF to save results.
Important: Small dosing errors can cause boron toxicity. If unsure, reduce the dose and test a small area first.