Repotting guide

When & how to repot Red Kohleria (Kohleria eriantha)

Also called Red Kohleria, Woolly Kohleria, Tree Gloxinia.

More about red kohleria

About Red Kohleria

Kohleria eriantha · also called Red Kohleria, Woolly Kohleria · tropical

Kohleria eriantha is a rhizomatous perennial in the Gesneriaceae family, native to Colombia, producing erect, velvety stems and brilliant orange-red tubular flowers spotted with yellow on the lower lobes. It thrives as a houseplant or conservatory specimen in bright filtered light with high humidity, and its underground rhizomes allow it to survive periods of dryness and facilitate easy propagation. The most important care fact is to never splash water on the densely hairy leaves, which trap moisture and develop rot patches or botrytis. Kohleria is not individually listed by the ASPCA; treat with caution around pets.

Mature size: 50–100 cm tall and 30–50 cm wide

Watch for — Rhizome rot from overwatering: Overwatering, especially in winter when the plant is semi-dormant, causes the rhizomes to blacken and decay; always let the top of the compost dry slightly before watering and ensure the pot has drainage holes that are not blocked.

How to tell red kohleria needs repotting

Repotting on a calendar is less reliable than reading the plant. For red kohleria, watch for these signs:

Roots spiralling thickly out of the drainage holes or pushing the whole plant up out of the pot.
The pot is so packed that water runs straight through in seconds and barely wets the soil.
It has split a plastic pot, or the rootball is a solid mass with almost no soil left when you slide it out.
Growth and (for red kohleria) flowering have clearly stalled despite good light and feeding — but remember this plant likes being snug, so a little crowding alone is not a reason to repot.

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 red kohleria

Only every 2–4 years, when genuinely crowded. Red Kohleria is one of the plants that genuinely prefers a snug pot — it grows and flowers better with its roots a little restricted, so resist the urge to repot it on schedule. Bushy, upright rhizomatous perennial with densely hairy, narrowly ovate leaves edged in red hairs and clusters of nodding, tubular orange-red flowers..

What size pot to step red kohleria up to

Go up only one pot size — roughly 2–3 cm (about an inch) wider in diameter, no more. Red Kohleria positively prefers a snug pot: it flowers and grows better when the roots are a little restricted. The single biggest repotting mistake here is over-potting — dropping red kohleria into a pot two or three sizes up. All that surplus soil holds water the small root system cannot use, stays cold and wet, and rots the roots within weeks. When in doubt, choose the smaller pot.

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 red kohleria

Early spring, just as new growth restarts, is the ideal window for red kohleria. 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 red kohleria

Confirm it actually needs it. Slide red kohleria out and check the roots. Only continue if it is genuinely packed — this plant prefers a snug pot, so if there is still soil and room, put it straight back.
Pick a pot only one size up. Choose a pot just 2–3 cm wider with good drainage. Resist anything bigger; over-potting is the main killer here.
Ease it out gently. Water lightly the day before, then tip red kohleria out, supporting the base. Tease the outer roots free only enough to stop them circling.
Repot at the same depth. Add a layer of fresh peat-free, well-draining, humus-rich potting mix, set the plant so the soil line sits exactly where it did before, and backfill around the sides, firming lightly.
Settle it in. Water once to settle the soil, then let it sit. Hold off on more water until the top of the soil dries — fresh soil around a small root system stays wet for a while.

Aftercare

Because the new soil holds more water than the old crammed rootball did, ease right back on watering — let the top of the soil dry before you water red kohleria again, or you will rot the roots in the very pot you just moved it to. Keep it out of harsh direct sun for a fortnight. Do not fertilise for about 4 weeks — fresh mix already carries nutrients and feeding freshly disturbed roots scorches them.

The right soil mix for red kohleria

Red Kohleria wants peat-free, well-draining, humus-rich potting mix. A blend of multipurpose compost, perlite, and fine bark creates the open, moisture-retentive but freely draining structure that suits the rhizomes; repot in spring every 1–2 years. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting red kohleria — frequently asked questions

How often should you repot red kohleria?

Only every 2–4 years, when genuinely crowded for red kohleria. Only repot red kohleria every 2–4 years, and only when it is genuinely root-bound — it flowers and grows best slightly crowded. Step up just one pot size in spring using peat-free, well-draining, humus-rich potting mix. The key mistake is over-potting: a too-big pot stays wet and rots the roots.

What size pot does red kohleria need?

When is the best time of year to repot red kohleria?

Does red kohleria like to be root-bound?

Yes — red kohleria genuinely flowers and grows best when slightly pot-bound, so do not rush to repot it. The mistake to avoid is over-potting into a much larger pot: the excess soil stays wet, the roots cannot use it, and the plant rots. Only repot every few years and only one snug size up.

Should you fertilise red kohleria after repotting?

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