Soil & potting mix

Best soil for Burro's tail (Sedum morganianum)

Also called donkey tail, horse tail, lamb tail.

About Burro's tail

Sedum morganianum · also called donkey tail, horse tail · houseplant

Burro's tail is a Mexican trailing succulent with plump blue-green leaves arranged in dense braided strands. Leaves drop at the slightest touch, so it is best kept where it will not be brushed. Pet-safe and drought-tolerant.

Sedum morganianum (Crassulaceae), native to southern Mexico, recorded wild on vertical igneous cliffs in ravines of central Veracruz within tropical deciduous forest, an origin that explains its pendulous, hanging habit.

Drainage is critical: a cactus mix or potting medium heavily amended with perlite, pumice, baked clay or fine gravel.

Preferred mix: Free-draining succulent mix

Sources: hort.extension.wisc.edu, plants.ces.ncsu.edu, en.wikipedia.org

Why burro's tail needs this mix

Burro's tail 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.

Burro's tail 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 burro's tail 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 burro's tail; 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 burro's tail 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 burro's tail?

pH is not a concern for burro's tail — 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 burro's tail 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 burro's tail 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 burro's tail covers the timing and technique step by step.

Burro's tail soil — frequently asked questions

What is the best soil mix for burro's tail?

2 parts standard cactus or succulent compost : 1 part perlite or pumice : 1 part coarse grit or coarse sand. Burro's tail 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 burro's tail?

Standard potting compost on its own stays wet far too long for burro's tail; the lower leaves and stem base go soft and translucent first. A good bagged "cactus and succulent" mix works for burro's tail 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 burro's tail need a special pH?