Stock Solution Calculator for Gardening

Formula used

• Dilution: C1 × V1 = C2 × V2 → V1 = (C2 × V2) / C1
• Diluent: Vdiluent = V2 − V1
• Prepare stock (powders): Mass = C × V (after converting units to mg/L)

How to use this calculator

1. Select Mode based on what you are mixing.
2. Enter your strength values and choose the correct unit.
3. Set the final volume to match your sprayer or watering can.
4. Press Calculate to see stock and diluent amounts.
5. Use Download CSV/PDF to keep a mixing record.

Why stock solutions improve consistency

Stock solutions let you mix repeatable feeds by separating strength from volume. If you keep one concentrate at 10,000 ppm, a 200 ppm working mix is a 50:1 dilution. This approach reduces “eyeballing” and helps match label rates across sprayers, watering cans, and drip tanks.

Understanding units used in garden mixes

This calculator supports mass-based and volume-based concentration units. For powders, ppm (mg/L), g/L, % w/v, and mg/mL are practical. For liquids, mL/L and % v/v are common. Useful references: 1% w/v equals 10 g/L, and 1% v/v equals 10 mL/L. Internally, mass units are converted to mg/L and volume units to mL/L, so the dilution math stays consistent for convenience.

Typical dilution targets and batch sizing

Many foliar feeds and micronutrient mixes land between 50–400 ppm active ingredient, while some soil drenches run higher depending on product guidance. With a 5 L sprayer, moving from 100 ppm to 200 ppm doubles required stock volume. If your stock is 5,000 ppm and your target is 100 ppm, the stock fraction is 2%. Scaling batches is linear: 2 L needs 40% of the stock volume used for 5 L at the same target.

Measurement accuracy and recordkeeping

Small measuring errors matter most at low volumes. For example, a 1 mL error on a 20 mL stock dose is a 5% shift in strength. Using the same output units as your measuring tools helps. Saved runs keep recent mixes in-session, and CSV/PDF exports create a clear log for repeat applications and seasonal comparisons. Consistent records also support troubleshooting when plant response changes.

Storage, stability, and safe handling

Store concentrates in labeled, sealed containers away from heat and sunlight. Some mixes precipitate over time; shake and inspect before dosing. When preparing a solid-based stock, dissolve fully first, then top up to final volume for accuracy. Always follow product compatibility notes, and keep concentrates out of reach of children and pets. Rinse measuring tools promptly to prevent residue buildup.

FAQs

1) What is a stock solution in gardening?

A stock solution is a concentrated mix you store and dose later. You dilute a small measured amount into water to reach a target strength for spraying or watering.

2) Why does the calculator use C1 × V1 = C2 × V2?

That equation conserves the total active amount before and after dilution. It helps you compute the exact stock volume needed for a final batch at the desired concentration.

3) Can I use it for liquid concentrates as well as powders?

Yes. Choose mass-based units for powders and volume-based units for liquids. The tool converts units internally so you still get correct stock and diluent volumes.

4) What if my target is higher than the stock?

You can’t dilute upward. If the target is stronger than the stock, you need a stronger stock, a smaller final volume, or a different product concentration.

5) How accurate do my measurements need to be?

Aim for within 2–5% for routine feeding. Use syringes or graduated cylinders for small volumes, mix thoroughly, and re-check inputs when working at very low doses.

6) Do the CSV and PDF include my full history?

Exports include your saved session runs. If you refresh or start a new session, the saved list may reset, so download records after important mixes.