Special Potting Mixes for Houseplants: What Soil Do Monstera, Cacti, Orchids, and More Need?

All-purpose potting soil works fine for many plants — but far from all of them. If you want to create optimal conditions, reach for a specialized substrate. The right soil is half the battle when repotting. Here’s an overview of which plants need which mix, and why.

Aroids (Monstera, Philodendron, Pothos)

These tropical climbers grow epiphytically or on tree trunks in the wild. They need an airy, chunky substrate that drains water well. A mix of 40% coco coir or quality potting soil, 30% medium pine bark, 20% perlite, and 10% worm castings is ideal. Ready-made aroid mixes are also available from specialty retailers. Regular potting soil is too dense — waterlogging is a real risk.

Succulents and Cacti

Cacti and succulents are masters of drought. Their substrate needs to be extremely well-draining and dry out quickly. Ready-made cactus soil is a good base, though often still too rich in organic matter. Better: 50% cactus soil, 30% mineral components (pumice, lava grit, coarse sand), and 20% perlite. Keep organic content low — the more mineral, the better.

Orchids (Phalaenopsis and Others)

Epiphytic orchids like the popular Phalaenopsis need coarse, bark-based orchid mix. It retains moisture without suffocating the aerial roots. Medium to coarse pine bark (15–25 mm) with a bit of sphagnum moss and charcoal is ideal. Never use regular soil — the roots will suffocate in compacted substrate.

Ferns and Calathea

These rainforest plants like to stay evenly moist, but never soggy. A substrate of 40% potting soil, 30% coco fiber or peat substitute, 20% perlite, and 10% bark provides moisture retention along with good airflow. Ferns are sensitive to overly dense substrate.

Mediterranean Herbs (Rosemary, Thyme, Lavender)

Herbs from the Mediterranean need a well-draining, relatively nutrient-poor substrate. A mix of 50% seed-starting or herb soil and 50% sand or perlite mimics their natural habitat. In overly rich potting soil, they grow leggy, lose aroma, and become prone to fungal disease.

DIY Substrate: Mixing Your Own Pays Off

A homemade substrate is often better and cheaper than ready-made products. Basic ingredients for a well-equipped collection: quality potting soil, perlite or pumice, pine bark, coco fiber, and sand. With these five components, you can meet the needs of almost every houseplant — while knowing exactly what’s in the mix.

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