Repotting guide

When & how to repot Pencil-leaf Tylecodon (Tylecodon cacalioides)

Also called Pencil-leaf Tylecodon, Sulphur Butterbush.

More about pencil-leaf tylecodon

About Pencil-leaf Tylecodon

Tylecodon cacalioides · also called Pencil-leaf Tylecodon, Sulphur Butterbush · houseplant

A shrubby South African succulent with peeling yellow-grey bark and tufts of narrow, cylindrical grey-green leaves at branch tips. Grows larger than most Tylecodon in cultivation, reaching around 1 m. Winter-growing, summer-dormant. Bears yellow-green tubular flowers in late summer on leafless branches. Toxic to pets and livestock — contains bufadienolide compounds found across the genus.

Mature size: Up to 1 m (39 in) tall; main stem to 5 cm (2 in) in diameter

Watch for — Root rot from poor drainage: The most common problem in cultivation. Use a very gritty mix and a pot with multiple drainage holes. Do not use a saucer that retains water. In humid climates, raise the pot to improve air flow around the base.

How to tell pencil-leaf tylecodon needs repotting

Repotting on a calendar is less reliable than reading the plant. For pencil-leaf tylecodon, 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 pencil-leaf tylecodon

Every 2–3 years, into bone-dry mix. Pencil-leaf Tylecodon's growth habit — erect to spreading succulent shrub with peeling bark; larger-growing than most cultivated tylecodon — sets the pace. A shrubby South African succulent with peeling yellow-grey bark and tufts of narrow, cylindrical grey-green leaves at branch tips. Grows larger than most Tylecodon in cultivation, reaching around 1 m. Winter-growing, summer-dormant. Bears yellow-green tubular flowers in late summer on leafless branches. Toxic to pets and livestock — contains bufadienolide compounds found across the genus.

What size pot to step pencil-leaf tylecodon up to

Use a pot only one size up — or even the same pot with fresh gritty mix if the roots have room. Pencil-leaf Tylecodon 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 pencil-leaf tylecodon

Spring or summer, while pencil-leaf tylecodon 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 pencil-leaf tylecodon

Repot dry. Do not water pencil-leaf tylecodon 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 sandy, well-draining cactus 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 pencil-leaf tylecodon 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 pencil-leaf tylecodon 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 pencil-leaf tylecodon

Pencil-leaf Tylecodon wants sandy, well-draining cactus mix. A 50:50 mix of commercial cactus compost and coarse grit or pumice works well. The natural habitat is rocky Succulent Karoo — replicate this with a loose, open substrate. Use pots with large drainage holes and avoid saucers that collect water. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting pencil-leaf tylecodon — frequently asked questions

How often should you repot pencil-leaf tylecodon?

Every 2–3 years, into bone-dry mix for pencil-leaf tylecodon. Repot pencil-leaf tylecodon every 2–3 years into a snug pot of sandy, well-draining cactus 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 pencil-leaf tylecodon need?

When is the best time of year to repot pencil-leaf tylecodon?

Should you water pencil-leaf tylecodon after repotting?

No — not straight away. Repot pencil-leaf tylecodon 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 pencil-leaf tylecodon after repotting?

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