Articles · Plant care basics
Best potting soil for indoor plants: what to buy and six mixes to make
Published 2026-11-09
The best potting soil for most indoor plants is a peat or coir-based indoor mix with extra perlite. Two parts potting mix to one part perlite suits most leafy houseplants.
Succulents, orchids, and carnivorous plants need something different. The recipes are below.
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What good potting soil does
Roots need water and air at the same time. Good potting mix holds enough water to last a week and drains fast enough to let air back in.
Bagged “potting soil” for houseplants has no soil in it. It is a blend of a few ingredients, and each one has a job.
| Ingredient | What it does |
|---|---|
| Peat moss | Holds water and stays light. Hard to wet again once it dries out. |
| Coconut coir | Holds water like peat and wets again with ease. Made from coconut husks. |
| Perlite | White, puffed volcanic glass. Adds air and drainage. |
| Pumice | A heavier volcanic rock. Adds drainage and does not float to the top. |
| Orchid bark | Chunks of fir or pine bark. Makes big air gaps for thick roots. |
| Vermiculite | Holds water and nutrients. Good for seedlings and thirsty plants. |
| Compost or worm castings | Adds slow, gentle nutrients. |
| Coarse sand or grit | Adds weight and fast drainage for succulents. |
What to look for on the bag
- The words “indoor” or “houseplant” or “potting mix.”
- Peat or coir listed first, with perlite you can see as white specks.
- A bag that feels light for its size.
Most garden centers stock a mix like this. If you order online, The Sill sells a potting mix for houseplants in its plant care collection.
What to avoid
Garden soil and topsoil. They pack down hard in a pot. Water sits on top, and roots get no air. They can also carry weed seeds and bugs.
Mixes sold for “moisture control.” They hold extra water. That helps a hanging basket in summer sun. Indoors, with less light, the soil stays wet too long.
An old, open bag. Damp mix stored open can grow fungus gnats before you plant in it. Store an opened bag in a bin with a lid.
A layer of gravel in the bottom of the pot. It does not improve drainage. It takes up room the roots could use. A drainage hole does the job.
Six mixes by plant type
Measure by volume, not weight. A “part” can be a cup, a yogurt tub, or a bucket. Use the same scoop for each ingredient.
The add-ins can be hard to find in small towns. Amazon sells perlite, orchid bark, and pumice in small bags.
1. Everyday mix for leafy houseplants
- 2 parts indoor potting mix
- 1 part perlite
Use it for pothos, spider plant, peace lily, dracaena, Chinese evergreen, peperomia, and most figs.
2. Chunky mix for aroids and thick roots
- 2 parts indoor potting mix
- 1 part orchid bark
- 1 part perlite
Use it for monstera, philodendron, alocasia, anthurium, hoya, and snake plant. These plants have thick roots that rot in dense, wet soil.
3. Gritty mix for succulents and cacti
- 1 part indoor potting mix
- 1 part perlite or pumice
Or buy a bag of cactus and succulent mix and add a handful of pumice. Use it for jade plant, aloe vera, echeveria, zebra haworthia, string of pearls, and desert cacti.
Water should run through this mix in a few seconds.
4. Moist mix for ferns and prayer plants
- 3 parts indoor potting mix
- 1 part perlite
Use it for Boston fern, maidenhair fern, calathea, prayer plant, and nerve plant. These plants wilt if the soil dries out. The mix holds water but still has air in it.
5. Bark for orchids
- Orchid bark alone, or bark with a little sphagnum moss
A moth orchid grows on tree branches in the wild. Its roots rot in potting soil. Never use it.
6. Peat and perlite for carnivorous plants
- 1 part sphagnum peat moss
- 1 part perlite
Use it for a Venus flytrap. Buy plain peat and plain perlite with no added fertilizer. Fertilizer and potting soil kill these plants.
Two more to know
African violets want a light, fluffy mix. Buy a bag made for African violets, or lighten everyday mix with extra perlite.
Holiday cacti grow on trees, not in deserts. Give a Christmas cactus cactus soil with orchid bark or perlite mixed in.
Peat or coir?
Both work. Peat is the standard and holds a lot of water. It comes from bogs that take a long time to regrow, so some gardeners choose peat-free mixes.
Coir is the common peat-free choice. It wets again after it dries out, which helps if you forget to water. A plant can grow well in either one.
Does the pot change the mix?
Yes. A terracotta pot pulls water out through its walls, so the soil dries faster. Plastic and glazed pots hold water longer.
If you water too much, use a chunkier mix and a terracotta pot. If you forget to water, use the everyday mix and a plastic or glazed pot.
When to replace potting soil
Potting mix breaks down in a few years. The pieces get small, the air gaps close, and water stops draining.
Replace the mix when:
- Water pools on top for more than a few seconds.
- Water runs down the gap between the soil and the pot and does not soak in.
- A white crust builds up on the soil.
- The plant has been in the same mix for more than two or three years.
See how to repot a houseplant step by step for the full method.
Quick answers
Can I use outdoor potting mix indoors? It works in a pinch if you add perlite. It often holds more water than an indoor plant can use.
Can I reuse old potting soil? Not from a plant that had pests or root rot. Mix from a healthy plant can be refreshed with half new mix and extra perlite.
Does potting soil have fertilizer in it? Many bags include a starter dose that lasts a few months. Check the bag, and wait to feed until it runs out.
Why is there mold on my potting soil? White fuzz on top means the soil stays too wet. Scrape it off, water less often, and give the plant more light.