Best Soil for Indoor Plants: Match the Mix to Your Plant
The quick answer
Tropical foliage and aroids want a chunky bark-and-perlite mix. Succulents and cacti want a gritty mineral mix. Orchids want coarse bark, not soil at all. Using one dense bag of generic potting soil for all three is the most common houseplant mistake there is.
Find your group
Tropical foliage & aroids: chunky, airy, holds a little moisture
The biggest group by far. These plants grow thick, exploring roots and want bark, perlite, and coco chips around them: fast drainage with just enough moisture held between waterings.
Includes: Monstera, Pothos, Philodendron, ZZ plant, snake plant, peace lily, calathea, anthurium, fiddle leaf fig
Use: Molly’s Aroid Mix
Plant-specific guides: Monstera · Philodendron · Pothos · Snake plant · ZZ plant · Fiddle leaf fig · Calathea · Anthurium · Peace lily
Succulents & cacti: gritty, mineral, drains in seconds
Desert plants that store water in their leaves and rot in normal soil. They need a high-mineral mix that drains almost instantly and goes bone-dry between waterings.
Includes: Echeveria, jade, aloe, haworthia, lithops, most cacti, drought-tolerant bonsai
Full guide: Best soil for succulents and cactus
Orchids: coarse bark, not soil
Epiphytes that grow clinging to tree bark in the wild. Their roots need air moving around them. Packed into regular soil they suffocate quickly.
Includes: Phalaenopsis, Cattleya, Oncidium, Dendrobium, Vanda
Use: Molly’s Orchid Mix
Plant-specific guides: Best orchid potting mix · Do orchids need soil?
The three mixes at a glance
| Molly’s mix | Best for | Texture | Moisture |
|---|---|---|---|
| Aroid Mix | Tropical foliage, aroids, most houseplants | Chunky bark + perlite | Holds some, drains fast |
| Succulent Mix | Succulents, cacti, bonsai | Gritty mineral | Dries in seconds |
| Orchid Mix | Epiphytic orchids | Coarse bark | Airy, fast-draining |
Why one bag can’t cover everything
Walk into any garden centre and you’ll see bags labelled “indoor potting mix” as if every indoor plant wants the same thing. A Monstera wants a chunky mix that holds a little moisture. A succulent wants grit that dries in days. An orchid won’t grow in soil at all. Use the wrong one and the symptoms look identical, yellowing leaves and rot, but the cause is structure, not watering.
Most bagged potting soil is also simply too dense for a pot indoors. Outdoors, rain and soil life keep it open. On a shelf it compacts, holds water, and suffocates roots. The fix for nearly every struggling houseplant is a chunkier, faster-draining mix matched to the plant type.
The rule that covers most houseplants: when in doubt, choose more drainage, not less. Far more indoor plants die from soil that stays wet than from soil that drains too fast.
What about generic “potting mix”?
Generic potting mix is built as a do-everything outdoor and container medium, heavy on peat or compost to hold moisture. For most indoor plants that is the wrong direction: it stays too wet in a pot.
Soilless mixes like Molly’s skip the dense soil base and build structure from bark, perlite, and mineral grit instead, which is what indoor roots actually want. For the full distinction, see potting soil vs potting mix.
Common questions
What is the best soil for indoor plants?
There isn’t one. The best soil depends on the plant: a chunky bark-and-perlite mix for tropical foliage and aroids, a gritty mineral mix for succulents and cacti, and a bark-based mix for orchids. Match the plant to the group, then use the matching mix.
Can I use the same potting mix for all my houseplants?
Only loosely. A good chunky aroid mix covers the large tropical-foliage group, but succulents want grit and orchids need bark. Using one dense bag for everything is the most common reason indoor plants struggle.
Is potting soil or potting mix better for indoor plants?
For most indoor plants, a soilless potting mix. Bagged potting soil holds too much water in a pot and compacts over time. A soilless, bark-based mix drains better and keeps roots aerated.
Why do my indoor plants keep dying in store-bought soil?
Usually because the soil holds too much water for an indoor pot, causing root rot. Switching to a chunkier, faster-draining mix matched to the plant type fixes most cases without changing how often you water.
How often should I change the mix?
Refresh the mix every 12 to 18 months for most houseplants. Bark and organic content break down over time, and as they do the mix compacts and drains more slowly, which is when problems start.
Not sure which mix? Start with your plant type
Three pre-blended soilless mixes: one for tropicals, one for succulents, one for orchids. No guessing, no amending a bag yourself.
Shop all Molly’s mixes → · Take the free 60-second Soil Finder quiz →
