Repotting guide

When & how to repot Dragon's tongue (Hemigraphis repanda)

Also called Dragon's tongue, Dragon's tongue plant, Red ivy (genus name).

More about dragon's tongue

About Dragon's tongue

Hemigraphis repanda · also called Dragon's tongue, Dragon's tongue plant · tropical

Dragon's tongue (Hemigraphis repanda) is a low, creeping tropical from the Acanthaceae family, prized for narrow, toothed leaves that flush silvery-green to deep wine-purple. Its defining need is steady warmth and humidity: it sulks below 50% humidity, crisping at the edges, so consistent moisture in the air and soil matters more than anything else.

Mature size: Low and spreading: typically 15-23 cm (6-9 in) tall with a spread of 30-50 cm (12-20 in); stems trail and creep rather than climb.

Watch for — Leggy, faded growth: In too little light the stems stretch and the leaves lose their purple flush, reverting to plain green. Move to brighter indirect light and pinch back the tips to keep it compact and richly coloured.

How to tell dragon's tongue needs repotting

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

Roots poking out of the drainage holes or coiling visibly around the inside of the pot.
You are watering far more often than you used to because the rootball dries out within a day or two.
Water runs straight through and out the bottom without soaking in.
Top growth has slowed or new dragon's tongue leaves are noticeably smaller than older ones despite good light.

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 dragon's tongue

Every 12–18 months — sooner if roots show fast. Dragon's tongue's growth habit — a fast-spreading, low creeping evergreen perennial with a groundcover or trailing habit. stems root readily where nodes touch damp soil, forming dense mats, which makes it ideal for spilling over pot edges, carpeting terrarium floors, or edging in tropical gardens. — sets the pace. Dragon's tongue (Hemigraphis repanda) is a low, creeping tropical from the Acanthaceae family, prized for narrow, toothed leaves that flush silvery-green to deep wine-purple. Its defining need is steady warmth and humidity: it sulks below 50% humidity, crisping at the edges, so consistent moisture in the air and soil matters more than anything else.

What size pot to step dragon's tongue up to

Step up one pot size — about 2–3 cm (an inch) wider. Dragon's tongue grows fast, so it will fill that space within a season, but jumping several sizes at once still backfires: the unused soil stays soggy and rots even a vigorous root system. One size at a time, every year or so, is the rhythm.

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 dragon's tongue

Early spring, just as new growth restarts, is the ideal window for dragon's tongue. The plant is moving into its strongest growth phase and re-roots into fresh soil quickly. Avoid repotting in winter dormancy or, for flowering plants, while it is in bud or bloom — recovery is slowest then and you risk dropping the flowers.

Step-by-step: repotting dragon's tongue

Time it for spring. Repot dragon's tongue in early spring as growth restarts so it re-roots quickly into the fresh soil.
Choose one size up. Pick a pot about 2–3 cm wider with drainage holes. One step only — a much bigger pot stays soggy and rots roots.
Ease the plant out. Water lightly the day before, then tip dragon's tongue out and gently loosen any roots circling the bottom of the rootball.
Repot at the same depth. Put a layer of fresh moisture-retentive, free-draining mix in the new pot, set the plant so its soil line is unchanged, and backfill, firming lightly.
Water and pause feeding. Water once to settle the soil. Hold off fertiliser for about a month — fresh mix already has nutrients and feeding now burns new roots.

Aftercare

Water dragon's tongue once to settle the soil, then let the surface dry before watering again — fresh mix around the roots stays wetter than the old compacted ball, so the commonest post-repot mistake is overwatering. Keep it out of direct sun for a week or two while roots re-establish. Do not fertilise for about 4 weeks — fresh mix already carries nutrients and feeding freshly disturbed roots scorches them.

The right soil mix for dragon's tongue

Dragon's tongue wants moisture-retentive, free-draining mix. Use a peat-free mix of coco coir or quality potting compost lightened with perlite, plus a little vermiculite to hold moisture. The blend should stay damp without becoming claggy, which suits a plant that likes consistent moisture but resents standing water. Always pot into a container with drainage holes to prevent root 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 dragon's tongue — frequently asked questions

How often should you repot dragon's tongue?

Every 12–18 months — sooner if roots show fast for dragon's tongue. Repot dragon's tongue roughly every 12–18 months, in early spring as growth restarts. It grows fast and circles its pot quickly, so step up one size (about 2–3 cm wider) into fresh moisture-retentive, free-draining mix. Don't jump several sizes — that soggy excess soil is what rots vigorous roots.

What size pot does dragon's tongue need?

When is the best time of year to repot dragon's tongue?

Can you put dragon's tongue straight into a much bigger pot?

No. Even a fast-growing dragon's tongue should only go up one pot size at a time. A vastly oversized pot holds a reservoir of wet soil the roots cannot reach, which stays cold and soggy and rots the roots — the opposite of what you wanted.

Should you fertilise dragon's tongue after repotting?

Not immediately. Wait about 4 weeks after repotting dragon's tongue. Fresh mix already contains nutrients, and feeding freshly cut or disturbed roots burns them. Resume your normal feeding routine once you see new growth.