TheNaturePlanet

In winter, phalaenopsis orchids at home grow slowly, and some eager growers may consider dividing the plants to propagate more pots. But the question arises: is it safe to divide phalaenopsis in cold winter? Will it kill the plant?

First, the conclusion: Low winter temperatures are truly unsuitable for dividing phalaenopsis orchids! Why? Like humans, phalaenopsis becomes less active in cold weather. Its optimal growth temperature ranges from 15°C to 30°C. When the temperature drops below 10°C in winter, it essentially enters a "dormant" state, with extremely slow root and new shoot growth. Dividing the plant at this time is like forcing a hibernating phalaenopsis to "wake up and work"—it lacks the energy to regrow roots and adapt to a new environment.

Let’s examine how physically stressful division is for phalaenopsis. During division, the plant must be removed from its pot, inevitably damaging or breaking its roots. In warm spring and autumn, phalaenopsis has strong recovery capabilities, allowing wounds to heal quickly and new roots to emerge. However, in low winter temperatures, wound healing slows significantly, making it easier for bacteria and fungi to invade, leading to root or stem rot.

Additionally, winter air is dry. After division, the damaged roots of phalaenopsis have reduced water absorption capacity. Combined with slow evaporation in low temperatures, overwatering can easily cause root suffocation, while underwatering may lead to dehydration—making maintenance extremely challenging! Even if you move the plant to a heated room with a heater or air conditioner, the fluctuating indoor temperatures and dry air can still stress the orchid.

So when is the best time for division? Late spring to early summer is ideal, when the temperature stabilizes at around 20°C–25°C, just after the orchid has finished flowering and new shoots have emerged. Dividing at this time ensures rapid recovery and significantly higher survival rates. Here’s how to do it:

Control water for a few days before division to dry the sphagnum moss or growing medium, making it easier to remove the plant from the pot.
Use a sharp, disinfected scissors or blade to cut the plant at the point where aerial roots are present, ensuring each divided section has 3–4 healthy roots and 1–2 leaves.
After repotting, avoid watering immediately. Place the plant in a shaded, well-ventilated area to recover for one week before resuming normal care.

Dividing phalaenopsis in low winter temperatures is highly likely to cause problems! Unless you have a temperature-controlled greenhouse to maintain stable humidity and warmth, do not take the risk. Be patient and wait for spring to perform the "division feast"—you’ll surely harvest a batch of healthy new plants!