Repotting guide

When & how to repot Firesticks Plant (Euphorbia tirucalli 'Sticks on Fire')

Also called firesticks, red pencil cactus, sticks on fire.

More about firesticks plant

About Firesticks Plant

Euphorbia tirucalli 'Sticks on Fire' · also called firesticks, red pencil cactus · houseplant

Firesticks is the vividly coloured cultivar of the pencil cactus (Euphorbia tirucalli), a near-leafless succulent of slender pencil-thick stems that flush fiery orange, red and yellow in bright light and cool temperatures. It is a fast, sun-loving, very drought-tolerant Euphorbia. Its copious milky latex is notably caustic, so it must be handled with real care.

Mature size: Indoors typically 1-1.8 m (3-6 ft) tall; can become a large shrub or small tree if grown on outdoors in frost-free climates.

Watch for — Leggy, floppy stems: Low light causes weak etiolated growth. Move to a much brighter spot and support tall stems, as they are brittle and snap easily.

How to tell firesticks plant needs repotting

Repotting on a calendar is less reliable than reading the plant. For firesticks plant, 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 firesticks plant

Every 2–3 years, into bone-dry mix. Firesticks Plant's growth habit — upright, fast-growing, densely branching succulent shrub of slim cylindrical stems, essentially leafless, that colour up in bright light and cool weather. — sets the pace. Firesticks is the vividly coloured cultivar of the pencil cactus (Euphorbia tirucalli), a near-leafless succulent of slender pencil-thick stems that flush fiery orange, red and yellow in bright light and cool temperatures. It is a fast, sun-loving, very drought-tolerant Euphorbia. Its copious milky latex is notably caustic, so it must be handled with real care.

What size pot to step firesticks plant up to

Use a pot only one size up — or even the same pot with fresh gritty mix if the roots have room. Firesticks Plant 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 firesticks plant

Spring or summer, while firesticks plant 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 firesticks plant

Repot dry. Do not water firesticks plant 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 sharply draining cactus or 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 firesticks plant 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 firesticks plant 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 firesticks plant

Firesticks Plant wants sharply draining cactus or succulent mix. Use a gritty cactus/succulent blend with extra pumice, perlite or sand for fast drainage. Wet, dense soil causes root and base rot. A weighty pot helps support the tall, brittle stems. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting firesticks plant — frequently asked questions

How often should you repot firesticks plant?

Every 2–3 years, into bone-dry mix for firesticks plant. Repot firesticks plant every 2–3 years into a snug pot of sharply draining cactus or 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 firesticks plant need?

When is the best time of year to repot firesticks plant?

Should you water firesticks plant after repotting?

No — not straight away. Repot firesticks plant 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 firesticks plant after repotting?

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