Growli

Soil & potting mix

Best soil for Pleiospilos simulans (Pleiospilos simulans)

Also called African living rock.

More about pleiospilos simulans

About Pleiospilos simulans

Pleiospilos simulans · also called African living rock · houseplant

A South African mesemb forming low pairs of broad, flat-topped, brownish grey-green leaves heavily dotted to mimic weathered stone, lying almost flush with the ground. It produces large coppery-yellow autumn flowers. A superb camouflage succulent, it requires intense light, extremely gritty soil and disciplined, season-aware watering to avoid rot indoors.

Preferred mix: Extremely gritty, lean mineral mesemb mix

Watch for — Mealybugs and root mealybugs: Pests hide in the central fissure and around the roots. Check at repotting and treat promptly with alcohol or a systemic insecticide.

Why pleiospilos simulans needs this mix

Pleiospilos simulans is an easy-going houseplant — it just wants a free-draining general mix that holds some moisture but never stays soggy.

For the full picture on what makes up a good mix, see our guide to the main types of soil and potting media — it explains why each ingredient above behaves the way it does.

What goes wrong with the wrong mix

The wrong soil is one of the most common reasons pleiospilos simulans struggles, and the damage often shows up weeks later as a watering problem. For this species specifically:

Reusing tired, compacted old compost or skipping the perlite. A free-draining mix in a pot with a hole solves most "why is it struggling" cases for pleiospilos simulans.

pH — does it matter for pleiospilos simulans?

Pleiospilos simulans is not fussy about pH — a slightly acidic to neutral mix (around pH 6.0-7.0), which a standard peat-free compost provides, is perfectly fine. No testing needed.

If you want to check or adjust it, the soil pH guide walks through testing and the safe ways to nudge a mix more acidic or more alkaline.

DIY mix vs a bagged one

A decent bagged houseplant compost works for pleiospilos simulans as long as you mix in perlite for air. The simple DIY ratio above is cheap and more reliable than a budget bag alone.

Drainage and the pot

A pot with a drainage hole and a saucer you empty after watering is all pleiospilos simulans needs — the free-draining mix does the rest.

Refresh pleiospilos simulans's mix every 18-24 months; even good compost slumps and compacts, and fresh, airy mix is often the simplest fix for a tired plant. When the time comes, our repotting guide for pleiospilos simulans covers the timing and technique step by step.

Pleiospilos simulans soil — frequently asked questions

What is the best soil mix for pleiospilos simulans?

3 parts peat-free houseplant compost : 1 part perlite : 1 part orchid bark or coco chips (optional). Pleiospilos simulans is adaptable, but like most houseplants it still needs air at the roots — a mix that drains freely while holding a working moisture reserve.

Can I use normal potting soil for pleiospilos simulans?

Plain garden soil or a cheap, claggy compost compacts in the pot and slowly suffocates pleiospilos simulans's roots. A decent bagged houseplant compost works for pleiospilos simulans as long as you mix in perlite for air. The simple DIY ratio above is cheap and more reliable than a budget bag alone.

Does pleiospilos simulans need a special pH?

Pleiospilos simulans is not fussy about pH — a slightly acidic to neutral mix (around pH 6.0-7.0), which a standard peat-free compost provides, is perfectly fine. No testing needed.

Should I buy a bagged mix or make my own for pleiospilos simulans?

A decent bagged houseplant compost works for pleiospilos simulans as long as you mix in perlite for air. The simple DIY ratio above is cheap and more reliable than a budget bag alone.

How often should I refresh the soil for pleiospilos simulans?

Refresh pleiospilos simulans's mix every 18-24 months; even good compost slumps and compacts, and fresh, airy mix is often the simplest fix for a tired plant. A pot with a drainage hole and a saucer you empty after watering is all pleiospilos simulans needs — the free-draining mix does the rest.

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