Mulch Dye Mixing Calculator
Copy your label's two amounts. Get full and partial batch tickets.
Measure one batch at a time
These are water and concentrate amounts, not tank fill lines. Follow your product's mixing order and sprayer instructions.
A large label does not need a large batch
Does the label give a whole container plus a large water amount? Copy both quantities without first converting the recipe into a per-gallon rate.
In the illustration, 1 US gal of concentrate is 128 US fl oz. Divide by 40 US gal of water: 3.2 US fl oz per US gal water. For 5 US gal water, the total is 16 US fl oz. Chosen 2-US-gal water batches produce three tickets: 2 + 2 + 1 US gal water, with 6.4 + 6.4 + 3.2 US fl oz concentrate.
A 32-US-fl-oz bottle covers that arithmetic total with 16 US fl oz of purchased concentrate unused. This is unmeasured inventory, not leftover diluted mix. The tool does not decide whether or how either can be stored.
The calculation
Batch concentrate = batch water in L × concentrate per litre
Batch count = round up (total water ÷ chosen water per batch)
Whole bottles = round up (total concentrate ÷ bottle volume)
The last ticket uses only the remaining water. Batch and bottle counts use the exact entered decimal quantities before display rounding, so a decimal boundary does not silently add a batch or miss a bottle.
Does “oz” on your label mean fluid ounces or weight? They are not interchangeable. NIST Handbook 44, Appendix C (2023) distinguishes US liquid measures: 1 US gal = 128 US fl oz = 3.785411784 L. The UK/Imperial gallon is different. Imperial units, weight doses and rates per finished mixture are outside this calculator.
Why the label remains in charge
Hippie Mulch's color directions explicitly allow a large container-and-water recipe to be used in smaller amounts, and include a color-specific adjustment. PetraMax's product FAQ also describes different per-water rates for different appearance goals. Both pages were checked October 1, 2026; neither shows a publication date.
Those differences are why this worksheet starts blank. It does not pick a brand, reuse another product's rate, or turn a marketing coverage claim into an application quantity. Check your actual current label before entering its amounts.
Recoloring is not a depth calculation. If your task is replacing a missing layer, measure what remains and use the mulch refresh worksheet instead.
Mixing questions
How much mulch dye should I mix per gallon?
Use the current label for your exact product and application. There is no preset dose here. Enter the label's concentrate amount and its stated water amount; the calculator scales that pair without choosing a recipe.
Should I enter 2 gallons of water for a 2-gallon sprayer?
Not automatically. Water plus concentrate must fit the sprayer's working limit and required headspace. Choose a water amount after checking the sprayer and product instructions. This calculator does not determine a safe fill or exact finished volume.
What happens to the last partial batch?
It keeps the same entered label proportion. The calculator lists the remaining water and scales the concentrate to that water amount instead of applying a full-batch dose.
Can I enter ounces, a 15:1 ratio or a rate per finished mixture?
Only explicit liquid-volume amounts per water amount are supported. US fluid ounces are not weight ounces. Confirm an ambiguous ratio, ounce unit or finished-mixture instruction with the manufacturer before using this tool; do not guess which quantity is water.
Will the result tell me how much mulch I can recolor?
No. The inputs describe liquid amounts, not application coverage. The result does not judge suitability, color, drying time, longevity or whether recoloring can replace a measured mulch top-up.