Repotting guide

When & how to repot Three-Coloured Bladderwort (Utricularia tricolor)

Also called Three-coloured bladderwort, Three-colored bladderwort.

More about three-coloured bladderwort

About Three-Coloured Bladderwort

Utricularia tricolor · also called Three-coloured bladderwort, Three-colored bladderwort · flowering

Utricularia tricolor is a perennial terrestrial bladderwort native to South America, found across Brazil, Argentina, Bolivia, Colombia, Paraguay, Uruguay, and Venezuela, where it grows in seasonally wet grasslands and savannas. Named for its striking three-toned flowers — purple upper lobe, white lower lip, and yellow centre — it is one of the showiest bladderworts in cultivation. The most critical care point is using only mineral-poor water such as rainwater or reverse-osmosis water. No toxicity to cats or dogs has been established for this species.

Mature size: Rosette spreads 5–10 cm across; flower scapes typically reach 15–25 cm in height.

Watch for — Root rot from mineral water or stagnant trays: Tap water salts and algae buildup in the water tray can cause root damage; flush the tray weekly with fresh distilled or rainwater and replace the growing medium if the roots turn brown and mushy.

How to tell three-coloured bladderwort needs repotting

Repotting on a calendar is less reliable than reading the plant. For three-coloured bladderwort, 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 three-coloured bladderwort) 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 three-coloured bladderwort

Only every 2–4 years, when genuinely crowded. Three-Coloured Bladderwort 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. Low rosette of strap-like leaves with underground bladder traps on fine stolons; produces upright flower scapes bearing 2–6 showy blooms..

What size pot to step three-coloured bladderwort up to

Go up only one pot size — roughly 2–3 cm (about an inch) wider in diameter, no more. Three-Coloured Bladderwort 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 three-coloured bladderwort 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 three-coloured bladderwort

Early spring, just as new growth restarts, is the ideal window for three-coloured bladderwort. 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 three-coloured bladderwort

Confirm it actually needs it. Slide three-coloured bladderwort 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 three-coloured bladderwort 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 1:1 sphagnum peat and perlite or fine silica sand, 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 three-coloured bladderwort 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 three-coloured bladderwort

Three-Coloured Bladderwort wants 1:1 sphagnum peat and perlite or fine silica sand. Use a nutrient-free, acidic, freely draining mix such as 50% sphagnum peat and 50% perlite; do not add compost, soil, or fertiliser of any kind. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting three-coloured bladderwort — frequently asked questions

How often should you repot three-coloured bladderwort?

Only every 2–4 years, when genuinely crowded for three-coloured bladderwort. Only repot three-coloured bladderwort 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 1:1 sphagnum peat and perlite or fine silica sand. The key mistake is over-potting: a too-big pot stays wet and rots the roots.

What size pot does three-coloured bladderwort need?

When is the best time of year to repot three-coloured bladderwort?

Does three-coloured bladderwort like to be root-bound?

Yes — three-coloured bladderwort 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 three-coloured bladderwort after repotting?

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