Growli

Soil & potting mix

Best soil for Cushion Moss Selaginella (Selaginella martensii)

Also called Martens Spikemoss, Trailing Selaginella, Variegated Selaginella.

More about cushion moss selaginella

About Cushion Moss Selaginella

Selaginella martensii · also called Martens Spikemoss, Trailing Selaginella · houseplant

Selaginella martensii is a popular terrarium and houseplant spikemoss from Mexico and Central America, known for its arching, branching stems and bright green foliage — variegated cultivars also exist. It performs best in high humidity. No known toxicity; not listed by ASPCA as harmful.

Preferred mix: Moist, humus-rich, free-draining mix

Watch for — Root rot: Over-watering or poor drainage quickly leads to rot. Ensure containers drain freely and do not allow the pot to sit in standing water.

Why cushion moss selaginella needs this mix

Cushion Moss Selaginella 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 cushion moss selaginella 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 cushion moss selaginella.

pH — does it matter for cushion moss selaginella?

Cushion Moss Selaginella 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 cushion moss selaginella 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 cushion moss selaginella needs — the free-draining mix does the rest.

Refresh cushion moss selaginella'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 cushion moss selaginella covers the timing and technique step by step.

Cushion Moss Selaginella soil — frequently asked questions

What is the best soil mix for cushion moss selaginella?

3 parts peat-free houseplant compost : 1 part perlite : 1 part orchid bark or coco chips (optional). Cushion Moss Selaginella 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 cushion moss selaginella?

Plain garden soil or a cheap, claggy compost compacts in the pot and slowly suffocates cushion moss selaginella's roots. A decent bagged houseplant compost works for cushion moss selaginella 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 cushion moss selaginella need a special pH?

Cushion Moss Selaginella 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 cushion moss selaginella?

A decent bagged houseplant compost works for cushion moss selaginella 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 cushion moss selaginella?

Refresh cushion moss selaginella'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 cushion moss selaginella needs — the free-draining mix does the rest.

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