Example data table
| Scenario | Inputs | Output |
|---|---|---|
| Foliar mix | 2 ppm B, 10 L, 99% purity | ≈ 0.116 g boric acid |
| Watering can | 1 ppm B, 1 US gal, 99% purity | ≈ 0.022 g boric acid |
| Soil application | 0.2 g B/m² over 15 m², 99% purity | ≈ 17.2 g boric acid |
Examples are illustrative; adjust targets to your crop and soil test.
Formula used
This calculator converts a desired elemental boron target into grams of boric acid. Boric acid contains about 17.47% boron by mass.
- Solution dosing: Total boron (mg) = target ppm × liters.
- Convert to grams B: g B = mg ÷ 1000.
- Convert to boric acid: g boric acid = g B ÷ (0.1747 × purity).
- Stock dilution (optional): stock ppm = target ppm × dilution factor.
How to use this calculator
- Select an application mode: solution dosing or soil area application.
- Enter your target elemental boron level and choose units.
- Provide volume (for solutions) or area (for soil) and purity.
- Optionally set a dilution factor to prepare a stock solution.
- Press Calculate. Download CSV or PDF if needed.
Safety tip: start low, mix thoroughly, and keep records.
Practical guidance for boric acid dosing
Why boron accuracy matters
Boron supports cell wall formation, flowering, and fruit set, yet the line between deficiency and toxicity is narrow. Small measurement errors can shift a safe program into leaf scorch, reduced vigor, or yield loss. This calculator standardizes conversions so your inputs translate into repeatable grams, regardless of container size or unit system.
Interpreting ppm targets
In solution mode, ppm means milligrams of elemental boron per liter of final mix. The tool multiplies ppm by total liters to find total boron required, then converts to boric acid using the boron fraction in H3BO3. Use low starting targets for new crops, and avoid frequent applications without soil or tissue feedback.
Purity and product labeling
Labels can vary by grade and additives. Purity changes the effective boron delivered per gram of product, so the calculator adjusts using your entered purity. If your label lists “boric acid” with a percentage, use that value. When unsure, treat purity as lower to stay conservative and verify with a small test batch.
Stock solutions and dilution control
Stock mixing is useful when you need consistent dosing across repeated fills. Enter a dilution factor above one and provide a stock volume; the tool increases the stock ppm by the same factor. Mix the stock thoroughly, then measure dilution water carefully. Record the ratio used, and keep stock containers clearly labeled for safe handling.
Field notes and risk management
Keep a log of date, crop stage, target ppm or rate, weather, and observed response. Foliar applications are more sensitive under heat or drought; soil applications should be watered in for even distribution. If you see tip burn or chlorosis after dosing, stop further boron inputs and reassess with local agronomic guidance or a soil test.
FAQs
1) Is boric acid the same as elemental boron?
No. Elemental boron is the nutrient target. Boric acid is a source that contains only about 17.47% boron by mass. The calculator converts your boron target into the required boric acid weight.
2) What does ppm mean for this calculator?
ppm in solution mode equals mg of elemental boron per liter of final mixture. Multiply ppm by liters to get total mg boron required before converting to boric acid.
3) Should I use soil mode or solution mode?
Use solution mode for foliar sprays or watering mixes you measure by volume. Use soil mode when your plan specifies an elemental boron rate per area, such as g/m² or lb/acre.
4) How does purity affect the result?
Lower purity means less active boric acid per gram, so you need more product to deliver the same boron. Enter the label purity percentage to align calculations with your material.
5) Why is there a dilution factor option?
It supports stock solutions. If you make a concentrated stock and then dilute it, the calculator scales the stock concentration by your dilution factor and computes grams for the stock volume.
6) How can I reduce burn risk?
Start with low targets, apply evenly, avoid hot midday spraying, and do not repeat applications quickly. Track plant response and confirm with soil or tissue tests when possible.