Repotting guide

When & how to repot 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.

Mature size: 60-90 cm trailing

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

How to tell burro's tail needs repotting

Repotting on a calendar is less reliable than reading the plant. For burro's tail, watch for these signs:

Roots growing out of the drainage holes, or the rootball lifting the plant proud of the rim.
Soil that has shrunk away from the pot sides and no longer holds water.
The pot is unstable because the plant has grown top-heavy.
Old, compacted, broken-down mix that stays wet too long — for a succulent that is a rot risk, so refresh it even if the pot size is fine.

For the underlying biology of a pot-bound root system and why it stalls a plant, see our guide to spotting and fixing a root-bound plant.

How often to repot burro's tail

Every 2–3 years, into bone-dry mix. Burro's tail's growth habit — trailing succulent — sets the pace. 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.

What size pot to step burro's tail up to

Use a pot only one size up — or even the same pot with fresh gritty mix if the roots have room. Burro's tail stores water and rots in a large pot of slow-drying soil. A tight terracotta pot that dries fast is far safer than a generous plastic one. Never up-pot a succulent by several sizes.

Not sure of the exact diameter? Our pot size calculator takes the current pot and root spread and tells you the right next size — it deliberately recommends a single step up, never a big jump.

The best time of year to repot burro's tail

Spring or summer, while burro's tail is in active growth and warm, is best — roots recover fastest then, and the plant is not sitting in cool damp soil. Avoid repotting a succulent in winter dormancy.

Step-by-step: repotting burro's tail

Repot dry. Do not water burro's tail for several days first. Working with dry roots and dry mix dramatically lowers the rot risk for a succulent.
Pick a snug, fast-draining pot. Choose terracotta one size up at most, with a drainage hole. Have gritty free-draining succulent mix ready.
Tip it out and clean the roots. Slide the plant out, crumble off the old soil, and trim any black, mushy or dead roots with clean snips.
Pot into dry mix. Set burro's tail at its original depth in dry gritty mix, firming gently. Do not bury the stem deeper than it was.
Wait a week before watering. Leave it completely dry and out of harsh sun for about 7 days so any damaged roots callus. Only then water lightly.

Aftercare

Keep burro's tail completely dry and out of fierce sun for about a week so any nicked roots callus before they meet moisture; watering a freshly repotted succulent is the classic way to rot it. Then resume the normal lean, dry rhythm. Do not fertilise for about 3 weeks — fresh mix already carries nutrients and feeding freshly disturbed roots scorches them.

The right soil mix for burro's tail

Burro's tail wants free-draining succulent mix. Cactus mix with 30% perlite; terracotta pots help wick excess moisture. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting burro's tail — frequently asked questions

How often should you repot burro's tail?

Every 2–3 years, into bone-dry mix for burro's tail. Repot burro's tail every 2–3 years into a snug pot of free-draining succulent mix, ideally in spring or summer. Let it sit in dry soil and do not water for about a week afterwards so any nicked roots can callus. Over-potting and watering straight away is what rots succulents.

What size pot does burro's tail need?

When is the best time of year to repot burro's tail?

Should you water burro's tail after repotting?

No — not straight away. Repot burro's tail into dry mix and wait about a week before the first watering so any damaged roots callus over. Watering a freshly repotted succulent is the single most common way to rot one.

Should you fertilise burro's tail after repotting?

Not immediately. Wait about 3 weeks after repotting burro's tail. Fresh mix already contains nutrients, and feeding freshly cut or disturbed roots burns them. Resume your normal feeding routine once you see new growth.