Can You Trim Phalaenopsis Roots in Autumn? Get These Points Straight Before You Start

"It's autumn, and the roots of my Phalaenopsis look like a mess. Can I actually trim them?" There's really no absolute answer to this question, but most likely it's "yes, you can trim" - the catch is that you have to tell apart the roots that "should be cut" from the roots that "must not be touched," otherwise one snip of the scissors and the plant may not be saveable.

Why is root trimming so often brought up in autumn? In summer, with high temperatures and high humidity, Phalaenopsis roots either suffocate and rot inside the pot or decay from overwatering. By the time autumn arrives and the weather cools down, it is exactly the right time to clean up the bad roots - trim them now, when the temperature is neither too high nor too low, and the root system recovers quickly. It also stops the bad roots from spreading further and saves up strength for winter blooming. But if your Phalaenopsis roots are perfectly healthy, then don't fuss over them. After all, good roots are the key to absorbing water and nutrients, and cutting them will actually hinder growth.

So which roots exactly should be cut? Here's a simple way to judge: first gently ease the Phalaenopsis out of the pot - don't yank it - and use your hands or a small brush to clean the sphagnum moss and bark off the roots, then examine them one by one!

The first type is rotten roots. They feel soft, collapse when squeezed, and are either brown or black; some even ooze a sticky liquid and may smell musty. Keeping such roots only consumes nutrients and can make the good roots rot too, so they must be cut away completely. The second type is hollow roots. They look white, but feel empty when squeezed, without any plump texture. These roots have dried out from lack of water and have already lost their ability to absorb, so keeping them just takes up space and they should be cut as well. There are also those especially old roots that are blackened and brittle, snapping at the slightest touch - these can be cut too, freeing up space for new roots to grow.

But note: those plump, white, firm-feeling roots, or the slightly green, faintly translucent"crystal roots," are all good roots - no matter how messy they look, they absolutely must not be cut! These roots are the lifeblood of the Phalaenopsis. Cut them and the plant's absorption capacity drops sharply, which can cause yellow leaves and no blooms.

There are also finer points when trimming roots. Don't use kitchen scissors from home; it's best to use gardening scissors wiped with alcohol, or sterilise the blade over a flame, to avoid infecting the cut. When cutting, cut at the boundary between the bad root and the good root, and don't leave any diseased tissue behind, or it will come back. After trimming, don't pot it up straight away - get some carbendazim powder, dip the cut ends in it, then leave the plant in a ventilated, shaded spot for half a day to let the cuts dry before planting, which prevents pathogens from entering.

When potting it back, be sure to use fresh potting medium, such as sphagnum moss or bark; the old medium may harbour pathogens, so don't reuse it. When planting, don't bury the roots too deep - it's fine to leave some roots exposed. Phalaenopsis roots can breathe air, and burying them too deep makes them prone to rot.

Autumn root trimming is not a mandatory task, but a way to deal with problems. If your Phalaenopsis roots are strong and healthy, with no rot or hollowness, then just water and fertilise steadily and wait for winter blooms; only when you find a problem with the roots do you need to take action and trim. Many growers, simply because their"hands itch," insist on cutting perfectly good roots, and end up killing the plant - a real shame.