How to Repot an Orchid (Without Killing It)

Repotting is the orchid job people put off the longest, and the one their orchid needs most. Shop phalaenopsis usually arrive crammed into sphagnum moss inside a plastic sleeve pot, and two years later the medium has decayed into a soggy sponge that suffocates the roots — the slow-motion cause of most "my orchid suddenly died" stories. The operation itself takes fifteen minutes, and orchids tolerate it far better than their delicate reputation suggests. Here's exactly when and how, focused on the moth orchid (Phalaenopsis) but valid for most bark-grown orchids.

When to repot

• Every 1–2 years: bark breaks down on that schedule; decayed bark holds water like a sponge and roots rot.
• Right after a flowering cycle ends is the ideal moment, or when you see fresh green root tips — the plant re-establishes fastest while making new roots. Avoid repotting in full bloom unless roots are rotting; it usually costs you the flowers.
• Sooner, regardless of timing, if: the medium stays wet for a week+, smells sour, or has turned crumbly and soil-like; roots inside the pot are brown and mushy; or the plant rocks loosely in decayed medium.

Roots wandering out of the pot into the air, on their own, are NOT a reason to repot — aerial roots are normal phalaenopsis behaviour.

What you need

• Fresh orchid bark mix (fir/pine bark, often with perlite and charcoal). Not standard potting soil — it suffocates orchid roots. Pure sphagnum only for very dry homes and experienced waterers.
• A clear pot with drainage holes, the same size or one size up (2–3 cm wider). Orchids flower best slightly root-bound; an oversized pot stays wet and rots roots.
• Scissors or snips sterilised in flame or with rubbing alcohol — orchid viruses and bacterial rots spread on dirty blades.

Soak the fresh bark in warm water for an hour (or overnight) while you work — pre-moistened bark settles better and wicks evenly afterwards.

Step by step

• Water the orchid a day before — hydrated roots are flexible instead of brittle.
• Squeeze the pot gently and slide the plant out. Tease away ALL the old medium, including moss packed in the root centre — this old core is the usual rot culprit.
• Rinse the roots and inspect: healthy roots are firm, silvery-green (bright green when wet); dead ones are brown, hollow or mushy, and the outer layer slides off leaving a thread.
• Cut every dead root back to firm tissue with your sterilised scissors. Removing half the root mass looks brutal and is completely routine. Trim spent flower spikes at the base too.
• Set the plant in the pot with the base of the lowest leaf just below the rim. Pour in bark around the roots, tapping the pot and wiggling gently so pieces settle into the gaps — firm enough that the plant doesn't wobble. Leave aerial roots above the surface; forcing them under usually rots them.
• Don't bury the crown — the junction of leaves and roots must sit at, not under, the surface.

Tip: a wobbly orchid never roots in. If it still rocks after potting, anchor it to a stake for the first couple of months — stability is what lets new roots grip.

Aftercare

Water thoroughly once after potting, then hold off for about a week so any cut roots can callus, and keep the plant out of direct sun in a bright spot with good humidity. Resume normal watering (roughly weekly, when roots turn silvery) and half-strength feeding after 2–3 weeks. A slight sulk — a limp lower leaf or a paused flower spike — is normal for a few weeks. New root tips are your confirmation that the repot worked.

Not sure whether those roots are dead or just dry? The PlantMe app's plant doctor can tell from a photo — it recognises rot, dehydration and sunburn among 500+ problems and walks you through the fix.