Calculator Inputs
Example Data Table
| Scenario | Target | Volume / Area | Product Strength | Purity | Efficiency | Estimated Product Needed |
|---|---|---|---|---|---|---|
| Fertigation iron batch | 5 ppm Fe | 1,000 L | 13% Fe | 100% | 90% | ≈ 427 g |
| Foliar zinc spray | 2 ppm Zn | 200 L | 15% Zn | 98% | 85% | ≈ 32 g |
| Soil boron correction | 0.5 mg/kg B | 50 m², 15 cm, 1.3 g/cm³ | 20% B | 100% | 90% | ≈ 2.7 kg |
Formula Used
Solution dosing
- Element (mg) = Target (ppm) × Volume (L)
- Element (g) = Element (mg) ÷ 1000
- Product (g) = Element (g) ÷ (Assay × Purity × Efficiency)
- Product per 100 L (g) = Product (g) ÷ Volume (L) × 100
Soil application
- Soil mass (kg) = Area (m²) × Depth (m) × Bulk density (kg/m³)
- Element (mg) = Target (mg/kg) × Soil mass (kg)
- Product (kg) = Element (g) ÷ (Assay × Purity × Efficiency) ÷ 1000
- Product per m² (g) = Product (kg) ÷ Area (m²) × 1000
How to Use This Calculator
- Select Solution / Tank Mix for fertigation or foliar tanks, or Soil Application for incorporation.
- Pick the micronutrient and enter your product’s element %.
- Enter purity and a realistic efficiency to account for losses.
- For solution mode, set target ppm and total volume.
- For soil mode, set mg/kg target, depth, and bulk density.
- Click Calculate Dose. Results appear above the form.
- Use Download CSV or Download PDF to save your report.
Target setting based on delivery method
Micronutrient targets depend on whether nutrients are delivered through a tank, a sprayer, or soil incorporation. In solution mode, ppm equals mg per liter, so targets scale directly with batch volume. For soil mode, mg/kg targets are applied to the estimated soil mass within the selected depth, making area and bulk density essential.
Product strength, purity, and efficiency adjustments
Commercial sources vary widely: chelates, sulfates, borates, and blended mixes may list elemental percentages that must be converted into true product mass. Purity accounts for inert material, while efficiency represents practical losses from runoff, fixation, uneven spreading, or incomplete uptake. Using these factors avoids under-dosing that fails to correct symptoms and over-dosing that risks burn or toxicity.
Soil mass estimation and incorporation depth
Soil application calculations hinge on the soil mass in the treated layer. The calculator estimates this using area × depth × bulk density, with common garden ranges around 1.1–1.5 g/cm³. Deeper incorporation increases soil mass and therefore raises required product. For banded applications, use the treated strip area rather than the full bed area for realistic doses.
Example data for quick verification
Use the examples below to sanity-check inputs and results. If your output differs greatly, re-check units, strength %, and the selected mode.
| Mode | Target | Volume / Area | Strength | Purity | Efficiency | Approx. Product |
|---|---|---|---|---|---|---|
| Solution | 5 ppm Fe | 1,000 L | 13% | 100% | 90% | ~ 427 g |
| Solution | 2 ppm Zn | 200 L | 15% | 98% | 85% | ~ 32 g |
| Soil | 0.5 mg/kg B | 50 m², 15 cm, 1.3 g/cm³ | 20% | 100% | 90% | ~ 2.7 kg |
Operational controls and recordkeeping
After calculating a dose, apply uniformly, then monitor crop response and confirm with follow-up testing when possible. For foliar and fertigation, keep mixing order consistent and avoid incompatible concentrates. For soil applications, distribute evenly and incorporate to the intended depth. Save CSV/PDF exports to build a repeatable nutrient program and track cost per treatment over time.
FAQs
1) What does ppm mean in solution mode?
In solution mode, ppm is equivalent to mg/L. Multiply the target ppm by total liters to get the elemental milligrams required for the entire batch.
2) Which efficiency value should I use?
Use 80–95% for controlled fertigation, and lower values for foliar sprays or soil applications where losses and fixation are higher. When unsure, start conservative and adjust using results.
3) How do I find the product strength percent?
Check the label for elemental content, such as “Fe 13%” or “Zn 15%”. Enter that elemental percentage as product strength, not the salt or chelate percentage.
4) Why does soil mode ask for bulk density?
Bulk density converts treated soil volume into mass. Since mg/kg targets depend on soil mass, higher bulk density or deeper incorporation increases the calculated micronutrient requirement.
5) Can I use this for raised beds or containers?
Yes. Use soil mode for incorporation and enter the bed’s surface area and depth. For container solutions, use solution mode with the actual tank volume you mix.
6) How should I handle blended products with multiple micronutrients?
Run the calculator for each nutrient using its listed elemental percent. If only a combined label is given, use product specifications or a datasheet to obtain individual elemental percentages.
7) Does this replace lab testing and crop guidance?
No. This tool helps convert targets into product mass. Safe and effective targets should come from soil or tissue testing, crop recommendations, and local agronomy guidance.