How to repot an orchid

How to repot an orchid

1. 01

   When to repot an orchid

   The RHS and the Missouri Botanical Garden say about every two years, the American Orchid Society says every one to three years. The state of the bark matters more than the calendar: it slowly breaks down into fine, soil-like crumbs, holds water too long and stops the roots getting air.

   It is time when brown particles wash out of the pot as you water, when the bark at the drainage hole no longer feels firm, when the mix stays wet long after watering or when the plant has outgrown its pot.

   The best time is after flowering, once new roots with green tips or a new leaf appear. Avoid repotting an orchid in bloom: the Missouri Botanical Garden says it will lose its flowers.

2. 02

   What you need

   Fresh bark-based orchid mix, never regular potting soil. The RHS warns that multipurpose and loam-based compost will kill moth orchids.

   A pot with good drainage holes. A clear plastic pot lets you see the roots and moisture, a clay pot is heavier and dries out faster. You also need sharp, clean pruners that you sterilize between plants, and a small stake if the plant is top-heavy.

3. 03

   Step 1: Take the orchid out and remove the old bark

   Hold the plant by the stem and ease it out of the pot. If roots cling to the pot, soak it in water until they come loose, or cut a plastic pot open.

   Pick all of the old bark out from between the roots or rinse it away with tepid water. Do not reuse old bark.

4. 04

   Step 2: Check the roots and cut off dead ones

   Healthy roots are plump and firm, silvery white or green. Dead roots are brown, hollow, mushy or dry and wiry. If you are unsure, squeeze gently: a live root is solid, a dead one collapses.

   Cut dead roots off with clean pruners. The RHS also shortens very long healthy roots to about 12 cm (5 in). Leave healthy aerial roots alone, they are normal on orchids.

5. 05

   Step 3: Pot it up

   Choose a pot the roots fit into without bending. Extra mix stays wet and can rot the roots. Often the same pot with fresh bark is enough.

   Put a thin layer of mix in the bottom, center the plant and work bark between the roots until the point where roots meet stem sits at the surface and the lowest leaf sits just above it. Firm the bark gently. Do not bury aerial roots. Add a small stake if the plant wobbles.

6. 06

   Aftercare

   Water thoroughly and let the pot drain completely. The Missouri Botanical Garden soaks the pot in tepid water for about an hour. Never leave water standing in the saucer.

   Hold off on fertilizer for several weeks, as UF/IFAS advises. Keep the orchid in bright light out of direct midday sun and water again only when the bark is nearly dry.

7. 07

   Common repotting mistakes

   Using regular potting soil. Choosing a pot that is far too big. Repotting in full bloom. Cutting off healthy aerial roots. Leaving the pot standing in water.

Common questions