How do I know when to repot my orchid?
Miltoniopsis orchid that needs to be repotted, with old media that is turning black as well as overgrown roots.
There are two main indicators that your orchid needs to be repotted. First, you need to repot when the potting media starts to break down. Old media breaks apart easily and/or turns black. Orchids need air circulation around their roots, and as the media breaks down, the air circulation is reduced. Sphagnum moss breaks down quickly and usually needs to be replaced one to two years. Orchid bark lasts a bit longer, needing to be replaced every two to three years.
Second, it is time to repot when the new root growth can no longer fit in the current pot. When this happens, new roots emerge, and it generally looks like the orchid can no longer fit in its current pot. When this happens, a larger pot is needed to support the continued growth of the orchid.
The best time to repot is when the plant and roots are actively growing, usually spring to early summer. With many orchid types such as phalaenopsis, oncidium, and cattleya, you can tell when roots are actively growing. When you can see green tips on the new root growth, it is generally a good time to repot. One exception to this rule of thumb is if there is active root growth at the same time that the orchid is blooming. You do not want to repot while the orchid is blooming, as the stress of repotting will likely cause the plant to drop its flowers and/or buds.
If you are using an orchid bark mix, soak the media in a bucket overnight. Dry bark can be very hydrophobic and repel water unless soaked. To begin, soak your orchid in room temperature water for about 15 minutes prior to repotting. This makes the roots more pliable and less susceptible to damage. Gently remove the media from around the roots. Remove any dead roots with a clean scissors. Place the roots into a clean pot that allows the roots and the new potting medium to fit snug in the pot while allowing some room to grow, and fill with media. If all the roots fit into the same size pot there is no need to put it in a bigger pot.
Once you have an idea about how often you enjoy watering your orchid, you can also change the potting medium as needed to match your desired watering frequency. For example, if you tend to overwater your orchid, and after a week the orchid seems to be soggy in sphagnum moss, try repotting the orchid in a bark mix. Conversely, if your orchid is potted in a bark mix, and it seems the roots in the pot dry out quickly and you feel you just can’t water it enough, try repotting the orchid in sphagnum moss.
Photo courtesy of Cathleen Daghestani
