Growing projects
Turn your chosen bonsai or terrarium mix into a measured shopping list
A mix calculator can answer how much of each chosen material to prepare. It cannot determine that those materials, proportions or a watering schedule suit a species and its environment. Keep the horticultural decision and the quantity calculation separate.
Measure the space the mix will actually occupy
Use internal dimensions or a suitable measured fill volume. Outside pot dimensions include wall thickness. Roots, stones, drainage layers and decorative structures displace material; an irregular terrarium may not resemble a rectangular box closely enough for one geometric estimate.
Use an allowance because you deliberately want spare material, not because a universal waste percentage exists. Record whether the measurement is loose or compacted volume. Different materials and handling can make that distinction matter.
Scale a hypothetical 50/25/25 mix
The default example starts with 12 litres of measured fill and a 10% allowance. Total mix is 13.2 litres. With user-chosen shares of 50%, 25% and 25%, prepare 6.6, 3.3 and 3.3 litres respectively.
Those proportions are an arithmetic illustration. Material A, B and C do not stand for a recommended bonsai soil, terrarium recipe or animal substrate. The tool requires shares to total exactly 100%, including decimal combinations such as 66.6%, 33.3% and 0.1%.
Compare quantities with the packages you can buy
An actual shopping decision also needs package sizes, existing stock and whether leftover material will remain useful. A smaller unit price can still produce a larger total purchase and more unused inventory.
Keep different recipes separate. It is reasonable to combine several pots only when you have deliberately selected the same materials and proportions for those projects. Combining them automatically could conceal an important care difference.
Bring observations back to the care decision
Species, weather, exposure, substrate, container and root condition affect care. General bonsai guidance emphasizes observing conditions rather than assuming every tree needs the same fixed schedule. Consult appropriate expertise for the specific project.
The tool supplies no pesticide, fertilizer, irrigation, animal-stocking or treatment instructions. Save your measurements and chosen recipe as a project record, then revise them deliberately when the underlying horticultural decision changes.
Primary references
Authored 2026-10-29. Arithmetic examples are covered by local regression tests. New workflow guides remain outside the indexing allowlist pending editorial and applicable specialist review. Examples use the assumptions stated here; authority guidance can change.