Soil Mix Recipe Calculator
Scale the perfect aroid, succulent, or fern mix to your exact pot volume.
Mix everything thoroughly while dry, then moisten before potting.
Why the right mix matters
The fastest way to kill a houseplant is to leave its roots sitting in dense, soggy soil. Each plant group wants a different balance of moisture retention and airflow, and these recipes are the tried-and-tested ratios most growers reach for.
The recipes
- Aroid: chunky and airy, made from potting mix, perlite, bark, and a little charcoal.
- Tropical foliage: a lighter version of standard mix with extra perlite.
- Succulent & cactus: mostly grit and perlite for fast drainage.
- Fern: moisture-retentive with coco/peat, still kept open with perlite.
- Orchid: mostly bark with charcoal and a touch of moss.
Frequently Asked Questions
What is a "part" in a soil recipe?
A part is just a unit of volume, whatever scoop or cup you use. A 2:1:1 mix means 2 scoops of the first ingredient to 1 each of the others. This calculator turns those parts into real liters and quarts for your pot.
Why add perlite or bark instead of using bag soil straight?
Most bagged potting soil is too dense and holds water too long for tropical houseplants, which causes root rot. Perlite adds air, and bark creates chunky gaps that let roots breathe, closer to how aroids and many houseplants grow in the wild.
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