Soil & potting mix
Best soil for Compton's Gibbaeum (Gibbaeum comptonii)
Also called Compton's Gibbaeum.
More about compton's gibbaeum
About Compton's Gibbaeum
Gibbaeum comptonii · also called Compton's Gibbaeum · houseplant
Compton's Gibbaeum is a compact South African mesemb from the Western Cape with paired, unequal succulent lobes and a velvety, greyish-green surface. It blooms in late autumn to winter with small white or pale pink flowers. Like all Gibbaeum, it demands full sun, near-total summer drought, and sharply draining gritty soil.
Preferred mix: Very gritty, low-nutrient succulent mix with 50–70% inorganic material
Why compton's gibbaeum needs this mix
Compton's Gibbaeum stores water in its leaves and stems, so it wants a free-draining, gritty mix that dries out fully between waterings — not a moisture-holding one.
- Compton's Gibbaeum carries its own water supply in its thick tissue, so the soil's job is to drain fast and then get out of the way.
- Its roots are adapted to short wet spells followed by long dry ones — a mix that stays damp removes the dry phase they depend on.
- A gritty mix also keeps the plant compact and well-coloured rather than soft, leggy and prone to collapse.
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 compton's gibbaeum struggles, and the damage often shows up weeks later as a watering problem. For this species specifically:
- Standard potting compost on its own stays wet far too long for compton's gibbaeum; the lower leaves and stem base go soft and translucent first.
- Big plastic pots full of dense mix hold a wet core long after the surface looks dry — that hidden wet zone is where rot starts.
- Anything sold as "moisture control" is the opposite of what this plant wants.
Treating compton's gibbaeum like a leafy houseplant and using plain compost. It needs at least half its volume as grit, perlite or pumice to survive long term.
pH — does it matter for compton's gibbaeum?
pH is not a concern for compton's gibbaeum — anything from mildly acidic to neutral (6.0-7.0) works. Get the drainage right and pH looks after itself.
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 good bagged "cactus and succulent" mix works for compton's gibbaeum if you add roughly 30-50% extra perlite or grit. Mixing your own from the ratio above gives you full control of how fast it dries.
Drainage and the pot
Use a pot with a drainage hole and empty the saucer within minutes of watering. Terracotta is more forgiving than glazed or plastic because it dries the rootball faster.
This mix decomposes slowly, so compton's gibbaeum only needs repotting every 2-3 years — mainly to refresh the grit and check the roots are firm and pale. When the time comes, our repotting guide for compton's gibbaeum covers the timing and technique step by step.
Compton's Gibbaeum soil — frequently asked questions
What is the best soil mix for compton's gibbaeum?
2 parts standard cactus or succulent compost : 1 part perlite or pumice : 1 part coarse grit or coarse sand. Compton's Gibbaeum carries its own water supply in its thick tissue, so the soil's job is to drain fast and then get out of the way.
Can I use normal potting soil for compton's gibbaeum?
Standard potting compost on its own stays wet far too long for compton's gibbaeum; the lower leaves and stem base go soft and translucent first. A good bagged "cactus and succulent" mix works for compton's gibbaeum if you add roughly 30-50% extra perlite or grit. Mixing your own from the ratio above gives you full control of how fast it dries.
Does compton's gibbaeum need a special pH?
pH is not a concern for compton's gibbaeum — anything from mildly acidic to neutral (6.0-7.0) works. Get the drainage right and pH looks after itself.
Should I buy a bagged mix or make my own for compton's gibbaeum?
A good bagged "cactus and succulent" mix works for compton's gibbaeum if you add roughly 30-50% extra perlite or grit. Mixing your own from the ratio above gives you full control of how fast it dries.
How often should I refresh the soil for compton's gibbaeum?
This mix decomposes slowly, so compton's gibbaeum only needs repotting every 2-3 years — mainly to refresh the grit and check the roots are firm and pale. Use a pot with a drainage hole and empty the saucer within minutes of watering. Terracotta is more forgiving than glazed or plastic because it dries the rootball faster.
Keep reading
- Compton's Gibbaeum care — the full brief (light, water, humidity, problems, pet safety)
- How often to water compton's gibbaeum — the schedule the mix feeds into
- Repotting compton's gibbaeum — when and how to refresh the mix
- Soil pH guide — test it and adjust it safely
- How often to water succulents — the soak-and-dry method
- Overwatered plant — signs and recovery
- Root rot — how the wrong soil starts it, and how to save the plant
- Best soil for peperomia 'napoli nights' (dark form)
- Best soil for peperomia floribunda
- Best soil for peperomia elongata
- All 8452 soil and potting-mix guides in the Growli library