Can Phalaenopsis survive division in high temperatures?

Once summer arrives, many flower lovers get itchy hands when they see the little offshoots sprouting on their Phalaenopsis, always wanting to divide and repot them. But people keep asking: in such hot weather, can Phalaenopsis be divided? Will it survive after division?

On hot days, it is best not to divide Phalaenopsis! Why is dividing in high temperatures so risky? Phalaenopsis is itself a tropical plant, but what it fears is a “stuffy hot sauna.” When dividing, you always have to use scissors and pry apart the roots, right? The wounds are exposed to temperatures above 30°C, and just like how wounds get infected easily in summer if not handled well, bacteria multiply absurdly fast, and within a few days the roots can rot and the stem can decay. Moreover, in hot weather Phalaenopsis itself is a bit “dozing off for the summer,” with a slow growth rhythm. Forcing a separation at this time is like making a weak person do heavy labor; of course it can hardly hold up.

So does that mean division is absolutely forbidden on all hot days? There are exceptions. If you have an air-conditioned room at home and can keep the temperature steady at 25-28°C, with good ventilation too, then you can give it a try. But if it is placed on a balcony or windowsill where daytime temperatures soar to 35°C and do not drop at night either, listen to me: do not touch it no matter what, and rather wait until autumn when it cools down.

If you really must divide in hot weather, remember the three-word formula: “fast, accurate, ruthless.” First, do sufficient preparation: sterilized scissors, carbendazim, and new sphagnum moss all ready in advance, so you are not scrambling when dividing. When dividing, locate the connection point precisely and cut it off in one snip; do not saw back and forth, because the neater the wound, the easier it recovers. After cutting, immediately apply carbendazim to the wound, like applying iodine to a wound, then place it in a cool, ventilated spot to dry for 4-6 hours to let the wound form a protective layer. If you skip this step, nine times out of ten the roots will rot.

Potting also has its particularities. Do not use too large a new pot; one size larger than the offshoot’s root system is enough. After soaking the sphagnum moss, squeeze out the water; if it can be clenched into a ball in your hand and does not scatter when released, the moisture is just right. Never stuff the sphagnum moss too tightly, or it will not breathe and will mold once it gets stuffy. After planting, do not water; first place it in diffused light to recover for 3 days, then use a spray bottle to mist around it to increase humidity, and water lightly only after a week.

There is another key point: after dividing, do not expose it to the sun! The summer sun is so harsh that even with diffused light, you must draw a gauze curtain at noon, or the leaves will scorch easily. If ventilation at home is poor, put a small fan blowing toward it (not directly at the offshoot); once the air moves, bacteria are less likely to breed.

To be honest, the risk of dividing in high temperatures far outweighs the benefit. Phalaenopsis is a slow-going thing, and we who grow flowers must also be patient. Wait until September when it cools down and the temperature drops to around 25°C; dividing then gives a survival rate at least eighty percent higher than in summer. Do not end up losing the old plant and breaking the little one too; that would be such a waste!