Potting Mix Batch Calculator
Choose a published volume ratio and set the batch size. The calculator scales each ingredient; it does not choose a recipe for your plant.
Scale a published mix recipe
Choose one cited recipe and enter the batch size. The calculator divides that volume by the published parts; it does not choose a recipe for your plant.
The starting 8-quart batch is an example. Complete recipe names, source contexts and dates are listed below.
Published recipes available in the scaler
- General soilless mix: peat and perlite (2:1)
One commonly used greenhouse soilless mixture listed by the source; not a plant-specific prescription.
Source: Texas A&M AgriLife Extension, Growing Media. Checked 2026-09-28.
- General soilless mix: peat, perlite, vermiculite (2:1:1)
One commonly used greenhouse soilless mixture listed by the source; not a plant-specific prescription.
Source: Texas A&M AgriLife Extension, Growing Media. Checked 2026-09-28.
- General soilless mix: peat, bark, perlite (2:1:1)
One commonly used greenhouse soilless mixture listed by the source; not a plant-specific prescription.
Source: Texas A&M AgriLife Extension, Growing Media. Checked 2026-09-28.
- Orchid/epiphyte mix: peat, fir bark, charcoal (1:6:1)
Published orchid-mix example for epiphytes; not a universal houseplant or aroid recommendation.
Source: University of Maryland Extension, Potting and Repotting Indoor Plants. Checked 2026-09-28.
The scaler divides the total batch volume by each recipe's sum of parts, then multiplies each ingredient's parts by that unit volume. The source link and context appear with the result.
What these recipes mean
These are source-published growing-media formulations. Some come from greenhouse or nursery production, and the orchid formula is a specialty epiphyte mix. They are shown as references, not as universal indoor-plant directions. Follow each source context and adjust only with plant-specific guidance.
All parts are measured by volume, using the same scoop or container for each ingredient. The calculator scales the stated parts to your target total; it does not add fertilizer or convert ingredient volume to weight.