Calculator Inputs
Example Data Table
| Scenario | Area | Coats | Coverage | Waste | Type | Result |
|---|---|---|---|---|---|---|
| Greenhouse benches | 18 m² | 2 | 12 m² per liter | 10% | Ready-to-use (500 ml) | ~3.30 L total, 8 bottles |
| Tool maintenance day | 120 ft² | 1 | 10 m² per liter | 15% | Concentrate (1:9) | ~1.28 L spray, 0.13 L concentrate |
| Plant supports and ties | 8 m² | 3 | 0.09 L per m² | 8% | Ready-to-use (1 L) | ~2.33 L spray, 3 bottles |
Formula Used
- Area conversion: ft² to m² uses 1 ft² = 0.09290304 m².
- Coverage normalization: If you enter “m² per liter”, we convert to liters per m² = 1 / (m² per liter).
- Base spray volume: Total Spray (L) = Area (m²) × Liters per m² × Coats.
- Waste adjustment: Spray After Waste (L) = Total Spray × (1 + Waste%/100).
- Ready-to-use containers: Ceiling( Spray After Waste ÷ Container Volume ).
- Concentrate dilution: For ratio c:w, concentrate fraction = c/(c+w), water fraction = w/(c+w).
How to Use This Calculator
- Measure the surface area you will treat (beds, benches, tools, or supports).
- Choose how many light coats you plan to apply.
- Enter a realistic coverage rate from your sprayer or label guidance.
- Add a waste factor if you spray outdoors or expect leftover liquid.
- Select ready-to-use or concentrate, then submit to see totals.
- Download CSV or PDF to store the plan for later sessions.
Usage Planning by Surface Type
Starch spray is often used on garden ties, labels, small tools, and work surfaces to add temporary stiffness and reduce fraying. Group your targets by type—benches, trellis parts, cloth ties, and tag surfaces—then measure each group and total the area. For small items, estimate area as length × width and multiply by quantity. This keeps refills predictable.
Choosing Practical Coverage Rates
Coverage depends on nozzle size, distance, and how wet your mist is. Light misting on smooth plastic or sealed wood can reach about 10–15 m² per liter. Porous fabric ties or unsealed wood often drop to 6–9 m² per liter. If you enter liters per m², a planning range of 0.07–0.17 works well. Start midrange, then adjust after one real session.
Coats, Finish, and Durability
Coats multiply volume, so choose them with intent. One coat suits quick touchups. Two thin coats usually beat one heavy coat because drying is more even and drips are reduced. Three coats can help reusable tags or cloth ties that must hold shape during training. Let each coat dry before the next to avoid pooling and patchy residue on smooth surfaces.
Waste Factors and Outdoor Conditions
Waste covers overspray, wind drift, and leftover liquid in the bottle. Indoors, 5–10% is often enough. Outdoors, 12–20% is safer—especially with wide fan nozzles, frequent station changes, or repeated priming. If you do short test bursts to tune the pattern, include them in waste. The “spray after waste” output helps you mix once and keep consistency.
Stocking Ready Mix vs Concentrate
Ready-to-use spray is fastest for small jobs, and the container estimate helps you stage enough bottles. Concentrates save storage space and allow ratios such as 1:9 or 1:4. The calculator splits your final spray into concentrate and water parts, so you can measure accurately and repeat the same strength across batches. Label mixed bottles with ratio and date, and shake before use.
FAQs
1) What coverage value should I use if I have no guidance?
Use 10 m² per liter for a light mist on smooth surfaces. If items absorb heavily or you spray very wet, lower coverage to 7–9 m² per liter and recalculate.
2) Why do coats change the result so much?
Each coat is another full pass across the same area. The calculator multiplies base spray by coats, which prevents under-mixing and helps you plan drying time and workflow.
3) How do I estimate area for thin ties or cords?
Approximate the treated band as length × average width. Calculate one piece, then multiply by the number of ties or cords to build a practical total area.
4) When should I increase the waste factor?
Increase waste for outdoor spraying, windy conditions, wide spray patterns, or frequent start-stop work. Priming a sprayer and short test bursts also add measurable waste.
5) How does dilution affect concentrate and water needs?
Dilution sets the fraction of concentrate versus water in the final spray. Total spray volume stays the same, while the calculator tells you the exact amounts to measure.
6) Can I keep a record of my results?
Yes. Download the CSV to log sessions and compare usage over time. Use the PDF for a clean printout to share with helpers on workdays.