Orchid plants, with the scientific name Orchidaceae, belong to the largest family of flowering plants, with more than 25,000 species. Most of these plants grow in the tropical and subtropical regions of the world. These plants may be epiphytic or terrestrial, and their roots have a spongy covering called velamen. It is sometimes necessary to trim their roots, particularly in the event of rot. While unhealthy roots should be trimmed back, it is essential not to harm the healthy roots, which are the plants’ lifeline. If you need to trim your orchid’s roots, this article will help you learn how to do so properly.
How to trim orchid roots
1. Peel back the layers of old potting mix.
To find the dead roots, you need to peel back the layers of old potting mix. Since this is a messy procedure, you should lay out some old newspapers or towels on your work table, and have a bucket or bin nearby for easy disposal. The old potting mix will make good compost for the garden.
2. Use sterilized garden tools and prepare a hydrogen peroxide solution.
Make sure your garden tools are all sterilized to avoid the spread of infection. Prepare a hydrogen peroxide solution to sterilize the shears and the orchid’s roots. Mix nine parts lukewarm water to one part common 3% hydrogen peroxide or 70% isopropyl alcohol. Put the solution in a spray bottle for use also during the pruning process.
Submerge the shears and other gardening tools in the solution for at least 30 seconds, then remove and let them dry on paper towels. The solution will also be used to disinfect the cut orchid roots and stems, to avoid a bacterial transfer.
3. Gently remove the orchid from the pot and rinse the roots with warm water.
Comb out the old potting mix with your fingers and rinse the roots with warm water. It helps dislodge potting mix from the roots and allows you to distinguish the healthy from the unhealthy roots.
4. Be sure to distinguish the healthy from unhealthy roots.
Healthy roots are silvery and turn greener as they become hydrated; plump, green roots mean they are sufficiently hydrated. Meanwhile, brownish, flattened roots indicate an unhealthy state. These roots are also soft, mushy and thin.
5. Cut off and dispose of all rotten roots.
Start the pruning process once you have properly identified the unhealthy roots. Tug on roots that look dead and see if their outer layer easily slips off. If so, cut these off as low as you can with a sterilized cutting tool. Cut at the base if the entire length is rotten.
Sterilize the shears between each cut by soaking them in the hydrogen peroxide solution for about 30 seconds. This kills bacteria and fungus and prevents them from spreading to the tools and other plants. Do not trim off the healthy roots; just let them be.
6. Treat the affected roots with a natural fungicide.
If the roots are severely affected with root rot and are brown and soggy, you should apply a natural fungicide. First, treat the cut roots with a hydrogen peroxide solution, then sprinkle them with cinnamon, and finally, apply a natural fungicide. Avoid overwatering your orchids, because waterlogged soil encourages the growth of root rot.
7. Cut down non-blooming flower stalks or spikes.
Non-flowering flower stalks or spikes should be cut down to save your orchid plant from unnecessary energy. Unhealthy orchids won’t bloom until they regain their vitality. Once the plants become healthy again new stalks will soon grow.
Reasons you should trim your orchid’s dead roots
Old potting mix holds moisture that leads to decaying roots.
Potting mix combined with old sphagnum moss and chronic moisture could result in an acidic environment. The potted roots will become prone to decay and die off if they are exposed to this acidic environment for a prolonged period. Orchids are often wrapped in sphagnum moss to keep the roots moist, but this can degrade due to frequent watering. Some orchid pots also do not have drainage holes, which results in waterlogged soil.
Dead roots that are untrimmed could lead to dehydration.
Orchids will have a decreased ability to absorb water if their potting mix has degraded and holds too much moisture. The roots become dehydrated and the healthy roots become fewer, which means less water is absorbed and the plant’s resources are strained.
Trimming dead roots and adding fresh potting mix stimulates the plant’s growth and ability to bloom.
Trimming off the dead roots can save your plant’s energy and improves its ability to bloom. The same thing happens when fresh potting mix is added, as it supplies the nutrients required for the plant to grow.
Decaying roots spread fungal infections and become a haven for bacteria.
Dying and decaying roots steal energy from the plant while decaying matter in your orchid’s potting mix becomes a breeding ground for bacteria and fungi. This could lead to a widespread infection that could damage your plant. Potting mix made of orchid bark degrades with time, so you should check your indoor orchids every few months and assess if they need to be repotted.
Orchids are perennial epiphytic or terrestrial plants that are popular for their gorgeous, multi-colored blooms. Their roots need special care, and occasionally need to be checked and trimmed, especially in the event of root rot. To trim orchid roots, you need to use sterilized gardening tools and be able to distinguish healthy roots from unhealthy ones. After cutting back the rotten roots, remember to treat the cut with a natural fungicide to help them regain their health.
Image: istockphoto.com / CemSelvi