Repotting Orchids: Care Guide for Optimal Growth

Orchids need a new substrate every 2–3 years. Pine bark decomposes, sphagnum becomes compact, roots push out of the pot. If you miss the timing, you risk root rot. The right time depends on the genus — and the condition of the roots, not the calendar.

When to repot?

Three indicators say regardless of the schedule: repot now.

• Substrate feels damp and musty for more than two days after watering
• Bark crumbles between fingers
• Roots push the pot upwards or grow out sideways

What you need

• New pot, one size larger (not two) — transparent for Phalaenopsis
• Fresh substrate suitable for the genus — see substrate guide
• Clean scissors or scalpel, wipe with alcohol before each cut
• Cinnamon powder for wound healing at cut sites
• Lukewarm water for an optional root bath

5 Steps to Repotting

1. Free the root ball from the old pot. For stuck roots, press the pot at the sides, cut open in an emergency. Do not tear.
2. Clean the roots. Remove old substrate with fingers. A lukewarm water bath for 10 minutes loosens stubborn residues.
3. Trim dead roots. Healthy roots are green or silvery-white and firm. Dead roots are brown, hollow, or mushy — cut back to healthy tissue, dust cut site with cinnamon.
4. Place in the new pot. Hold the plant by the leaves, gently insert roots. Let substrate trickle in from above and settle by lightly tapping the pot wall — do not press down.
5. Let dry for 3–7 days. Semi-shaded, no direct sun, no watering. The plant needs time to seal the cut sites.

Root Diagnosis: What stays, what goes?

• Green or silvery-white, firm: healthy — stays
• Brown, hollow, mushy: dead — cut away
• Black, slimy, smells musty: rot — cut away generously, at least 1 cm into healthy area
• Dried out but still firm: can recover — leave it

If you lose more than half of the roots after trimming, you should place the plant in sphagnum moss instead of bark — a more humid recovery climate.

After Repotting

Do not water for 3 to 7 days. Then return to normal watering. Fertilize again only after 4 weeks, when roots are healthy. Place in semi-shade, avoid direct midday sun.

Common Mistakes

• Pot too large. Orchids like tight pots — too much substrate stays wet, roots rot
• Watered immediately. Water on open cut sites leads to root rot
• Repotted during sheath formation. Plant drops buds
• Substrate too fine. Phalaenopsis bark coarse, young plants fine — mixed up leads to waterlogging
• Dull scissors. Crushes roots instead of cutting, wounds heal poorly

Frequently Asked Questions