Repotting guide

When & how to repot African Milk Tree (Euphorbia trigona)

Also called African milk tree, African milk bush, Cathedral cactus, Candelabra cactus, Friendship cactus, Good luck cactus.

More about african milk tree

About African Milk Tree

Euphorbia trigona · also called African milk tree, African milk bush · houseplant

The African milk tree (Euphorbia trigona) is an upright, candelabra-shaped succulent grown as an easy-care houseplant. Give it bright light, a gritty cactus mix and infrequent watering once the soil dries. It is not pet-safe: its milky latex sap irritates skin, eyes and the gut, so keep it away from pets and children.

Mature size: Can reach 6-12 ft (1.8-3.7 m) tall and 5-10 ft wide in the ground in frost-free regions; as an indoor pot plant it is typically kept to around 3-6 ft (0.9-1.8 m). Stems can be tip-pruned to control height and encourage branching.

Watch for — Soft, yellowing or mushy stems (root/stem rot): Almost always overwatering or poor drainage. Let the mix dry out between waterings, use a gritty cactus soil and a pot with drainage holes; remove rotted sections and re-root a healthy cutting if the base is lost.

How to tell african milk tree needs repotting

Repotting on a calendar is less reliable than reading the plant. For african milk tree, 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 african milk tree

Every 2–3 years, into bone-dry mix. African Milk Tree's growth habit — upright, columnar succulent with a candelabra or cathedral-like branching pattern. three- to four-sided ridged green stems are lined with short paired spines and small teardrop leaves along the ridges; the 'rubra'/'royal red' form flushes burgundy. a vigorous, fast grower that may need staking or repotting as it gains height. — sets the pace. The African milk tree (Euphorbia trigona) is an upright, candelabra-shaped succulent grown as an easy-care houseplant. Give it bright light, a gritty cactus mix and infrequent watering once the soil dries. It is not pet-safe: its milky latex sap irritates skin, eyes and the gut, so keep it away from pets and children.

What size pot to step african milk tree up to

Use a pot only one size up — or even the same pot with fresh gritty mix if the roots have room. African Milk Tree 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 african milk tree

Spring or summer, while african milk tree 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 african milk tree

Repot dry. Do not water african milk tree 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 cactus/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 african milk tree 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 african milk tree 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 african milk tree

African Milk Tree wants free-draining cactus/succulent mix. Use a gritty, fast-draining cactus or succulent mix, or amend standard potting soil with coarse sand, perlite or pumice. Prefers a sandy-to-loamy, acidic-to-neutral pH. Always plant in a container with drainage holes to prevent water sitting around the roots. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting african milk tree — frequently asked questions

How often should you repot african milk tree?

Every 2–3 years, into bone-dry mix for african milk tree. Repot african milk tree every 2–3 years into a snug pot of free-draining cactus/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 african milk tree need?

When is the best time of year to repot african milk tree?

Should you water african milk tree after repotting?

No — not straight away. Repot african milk tree 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 african milk tree after repotting?

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