Repotting guide

When & how to repot Thick-stemmed Aichryson (Aichryson pachycaulon)

Also called Thick-stemmed Aichryson.

More about thick-stemmed aichryson

About Thick-stemmed Aichryson

Aichryson pachycaulon · also called Thick-stemmed Aichryson · houseplant

A biennial or short-lived monocarpic succulent from the Canary Islands, notably Gran Canaria, growing in cloud-forest rock habitats at 700–1,100 m. It forms a rosette of fleshy, hairy leaves on a notably thick stem before flowering once then dying. Grow in bright filtered light, water moderately in growing season, and keep dry in winter.

Mature size: Up to 50 cm (20 in) tall in flower; vegetative rosette 20–30 cm (8–12 in) across

Watch for — Root rot from overwatering: Sitting in wet soil causes rapid stem and root rot. Ensure the pot drains freely and water only when the top of the soil is dry. Terra-cotta pots help wick away excess moisture.

How to tell thick-stemmed aichryson needs repotting

Repotting on a calendar is less reliable than reading the plant. For thick-stemmed aichryson, 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 thick-stemmed aichryson

Every 2–3 years, into bone-dry mix. Thick-stemmed Aichryson's growth habit — biennial monocarpic rosette-forming succulent; flowers once and dies, reaching up to 50 cm in height at full bloom — sets the pace. A biennial or short-lived monocarpic succulent from the Canary Islands, notably Gran Canaria, growing in cloud-forest rock habitats at 700–1,100 m. It forms a rosette of fleshy, hairy leaves on a notably thick stem before flowering once then dying. Grow in bright filtered light, water moderately in growing season, and keep dry in winter.

What size pot to step thick-stemmed aichryson up to

Use a pot only one size up — or even the same pot with fresh gritty mix if the roots have room. Thick-stemmed Aichryson 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 thick-stemmed aichryson

Spring or summer, while thick-stemmed aichryson 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 thick-stemmed aichryson

Repot dry. Do not water thick-stemmed aichryson 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 well-draining loam with added grit 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 thick-stemmed aichryson 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 thick-stemmed aichryson 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 thick-stemmed aichryson

Thick-stemmed Aichryson wants well-draining loam with added grit. Use a loam-based potting mix with 30% perlite or coarse sand. The cloud-forest habitat suggests slightly more moisture-retentive mix than true desert succulents require, but drainage must still be sharp to prevent basal rot. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting thick-stemmed aichryson — frequently asked questions

How often should you repot thick-stemmed aichryson?

Every 2–3 years, into bone-dry mix for thick-stemmed aichryson. Repot thick-stemmed aichryson every 2–3 years into a snug pot of well-draining loam with added grit, 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 thick-stemmed aichryson need?

When is the best time of year to repot thick-stemmed aichryson?

Should you water thick-stemmed aichryson after repotting?

No — not straight away. Repot thick-stemmed aichryson 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 thick-stemmed aichryson after repotting?

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