It is necessary to re-pot an Orchid when it’s growing medium has broken down, when it’s root structure is starting to weaken due to lack of growing room, or rotting roots as a result of poor medium/over watering . Re-potting is normally carried out every one to two years, preferably when the plant is actively growing which would usually be when the Orchid has finished flowering.
You will need
You should find a clean area such as a table or workbench to work on. It’s a good idea to lay several sheets of paper/newspaper down – it makes removal and disposal of the the old potting material much easier!
- Pot/s – Choose a new pot large enough to allow space for growth in the case of Sympodial Orchids (Cattleya, Miltonia etc). About 5cm larger is ideal. Monopodial Orchids (Phalaenopsis, Vanda) may not need a larger pot (depending on root growth and condition) and can sometimes be re-potted into their old pots. If there are many blackened or rotten roots a larger pot could make matters worse!
- Secateurs- These should be of the curved bypass type shown as these give a cleaner cut.
- Kitchen blow torch- Used to flame sterilise cutting tools as disease is easily spread between Orchids.
- Potting mix- You can make up your own if you’re feeling adventurous! I prefer to use readily available shop bought Orchid Mix such as the Orchid Focus repotting mix shown above. It’s a good idea to soak it in water the night before as it’ll help with water retention of the fresh bark. I follow a tip here that I picked up which is to use boiling water with a few tiny drops of dishwashing detergent to help “wet” the mix, as well as sterilize any fungus spores etc which may be present.
- Knife (not shown)- This can be useful to run around the inside of the pot to free the roots.
- You should prepare your Orchid for re-potting by watering it the day before you plan to do the work.
Step 1
Lay the Orchid pot on its side and gently remove it. If it’s a bit stubborn use the back (blunt) side of the knive blade to run around the edge of the pot.
Step 2
Shake the plant gently to remove the old potting material. Inspect the roots and cut away any that are damaged or dark/mushy. Only cut healthy pale green roots if they won’t fit into the new pot without excessive bending. Aerial roots should not be removed or buried when re-potting . If the Orchid is sympodial, remove some of the old backbulbs leaving mostly pseudobulbs in leaf.
Step 3
Put a handful of new mix into the bottom of the pot then hold the plant in position, in the middle for phalaenopsis etc, at the back of the pot for Cattleya etc.
Step 4
Still holding the Orchid in position, add more mix around the roots firming into position with your fingers or a lollypop stick or similar. Tap the pot gently after a few handfuls to settle the mix around the plant. Continue this process until the plant is supported but never cover the crown of a monopodial Orchid or the rhizome of a sympodial one.
Step 5
After you have finshed repotting, do not put the plant back in it’s normal growing area straight away. Place the plant in a shady spot away from bright sunlight for a couple of weeks, watering sparingly.
Authors bio is coming up shortly.
