Repotting guide

When & how to repot Spiked Kohleria (Kohleria spicata)

Also called Spiked Kohleria, Spike-Flowered Kohleria.

More about spiked kohleria

About Spiked Kohleria

Kohleria spicata · also called Spiked Kohleria, Spike-Flowered Kohleria · tropical

Kohleria spicata is a robust, rhizomatous gesneriad from Central America and northern South America, bearing spikes of pendulous, tubular red to orange-red flowers with yellow interiors spotted in purple. Softly hairy stems and dark-green, velvety leaves add tropical appeal. It thrives in warm, humid conditions with bright indirect light and grows vigorously in summer.

Mature size: 45–90 cm tall, 45–60 cm wide

How to tell spiked kohleria needs repotting

Repotting on a calendar is less reliable than reading the plant. For spiked 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 spiked 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 spiked kohleria

Only every 2–4 years, when genuinely crowded. Spiked 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. Upright, rhizomatous herbaceous perennial producing tall flowering spikes; may die back partially in winter.

What size pot to step spiked kohleria up to

Go up only one pot size — roughly 2–3 cm (about an inch) wider in diameter, no more. Spiked 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 spiked 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 spiked kohleria

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

Confirm it actually needs it. Slide spiked 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 spiked 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 rich, well-drained tropical 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 spiked 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 spiked kohleria

Spiked Kohleria wants rich, well-drained tropical mix. Use 2 parts peat-free all-purpose compost, 1 part perlite, and 1 part coir. A pH of 6.0–6.5 is appropriate. Rhizomes need good aeration to prevent rot. Shallow pots suit the rhizome structure. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting spiked kohleria — frequently asked questions

How often should you repot spiked kohleria?

Only every 2–4 years, when genuinely crowded for spiked kohleria. Only repot spiked 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 rich, well-drained tropical mix. The key mistake is over-potting: a too-big pot stays wet and rots the roots.

What size pot does spiked kohleria need?

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

Does spiked kohleria like to be root-bound?

Yes — spiked 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 spiked kohleria after repotting?

Not immediately. Wait about 4 weeks after repotting spiked 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.