Orchids can be easy to grow provided you tend to their few specific needs. When you consider the natural environment in which they thrive, it’s easy to understand why you cannot expect them to enjoy particularly cold, dry, or soaking wet conditions. Since winter is just around the corner, now is the perfect time to prepare in order to make sure that your orchids continue to flourish and make it through the winter unscathed.
Cold damage is visible just a few days after exposure to low temperatures. Temperatures don’t necessarily need to drop below freezing in order to cause damage so make sure that you keep a thermometer next to your plant. The severity of the damage will determine how quickly you notice the symptoms. Some of these symptoms are similar to those of other potential problems including root rot, lack of water, light stress, and heat stress. This makes cold damage somewhat difficult to diagnose at times. Symptoms to look for include pitting, lesions on the surface, sunken areas, discolouration (browning), slower growth than normal, increased susceptibility to bacteria and fungi. Your orchids could even die as a result of cold exposure.
The first step to preparing for winter is choosing the right orchids to suit your home or greenhouse. If you keep temperatures somewhat cooler than most orchids enjoy, then it’s best to avoid particularly sensitive varieties such as vanda or phalaenopsis. If you plan on keeping your home or greenhouse snug and warm over the winter, then any orchid should be more than happy during these colder months. Remember that seedlings and young plants are even more sensitive to the cold so take extra care with them. Make sure that temperatures never drop below 16 degrees Celsius and your orchids will be just fine. Of course, other factors like light and humidity are also important regardless of the season. When measuring the temperature in the room, keep the thermometer as close to the plant as possible. The higher your thermometer is set, the higher the temperature it will read. If you place your orchide near a window, you can expect the temperatures to be cooler than those further from the window.
Since many orchids need at least 14 hours of daylight every day, you cannot rely on natural light in winter. There simply aren’t enough hours in the day. The best thing to do is set up artificial lighting to keep your plants happy. Monitor humidity levels in the room as well since orchids thrive in humid environments. You will not need to water as often during these months and you can even hold off on fertilizing your plants until the weather warms up again.
If, despite your best efforts, your orchid is exposed to colder conditions than it should, don’t give up just yet! Treat your plant just as you would a repotted orchid. Avoid high temperatures and direct sunlight. Keep the potting soil moist and add a small amount of plant food and minor elements to help them sprout new growth. Continue this weekly liquid plant food programme along with light fertilizing until your plant has returned to normal.