7 Orchid Winter Care Tips for Thriving Plants All Season
Many orchids are tropical plants that need special care during the cooler months. Depending on the species, you may need to switch things up if you want to see them flower. Orchid enthusiast Melissa Strauss offers some tips on caring for your tropical beauties during the cooler months.

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Orchids are some of the most popular yet elusive houseplants. Most of the ones we find at nurseries and other retailers are tropical and have environmental needs specific to those regions. If you’re caring for your orchids in a tropical zone, little needs to happen during winter. Otherwise, there are some important shifts to make.
Much of orchid winter care centers around identifying their natural habitat and mimicking those conditions. Some are native to high elevations. Their cold tolerance might surprise you! Others prefer the warm, humid conditions of a greenhouse year-round.
Let’s talk about some important factors in winter care. I will try to address the different species as much as possible when it comes to temperature and moisture needs. This is where the greatest differences lie. Let’s dig in.
Keep Most of Them Warm

For the most part, orchids need warm, humid environments, even during winter care. The most common species kept as houseplants is Phalaenopsis. You might know these as moth orchids. They are not cold tolerant at all, and temperatures below 40°F (4°C) can be fatal.
Other species that absolutely need to stay warm include Vandas, some Dendrobiums (Phalaenopsis and antelope-type), Epidendrum, Brassavola nodosa, and Bulbophyllum. These are all classified as warm growing.
I prefer to keep my plants outdoors during the summer because it solves the moisture and circulation conundrum that often leads to root rot. Fungus grows in cool, damp places, so indoors, it’s much more common. While I leave certain orchids outside for an extra month once the weather begins to cool off, others need to come in if there is even a threat of temperatures near 40°F (4°C).
Once they are indoors, they are not out of the weeds yet. For these and the orchids you keep indoors year-round, it’s important to pay attention to the temperature where you have them placed in the home. Sometimes, in very cold weather, the temperature near your windows can be significantly colder than your thermostat.
You don’t want to deprive your orchids of light, but don’t leave them directly in a window where they may catch a chill. Keep them out of drafts as well. If your plant is near an egress that’s often opened, gusts of cold air can be damaging.
Give Some of Them a Bit of a Chill

We typically think of orchids as warm-climate plants that thrive in hot weather and suffer when things get cool. The reality is that there are species that grow naturally as far north as Greenland and Alaska. It’s not common to keep many of these in the home, however. Most of the species you will find available for purchase are tropical natives.
Even among the more common types, there is a range of habitats and temperature tolerance as a result. The best way to determine the temperature range your particular plant can tolerate is to determine its native range. Then, find out the average highs and lows in that place.
The more common, cold-tolerant species include Cattleya, Cymbidium, Dendrocoyne Dendrobium, and Oncidium. These are all sympodial orchids; they form pseudobulbs and require a period of winter dormancy if you want them to bloom. Many of them naturally occur at higher elevations, where the air cools more than it does near sea level in the same regions.
Miltonia and Masdevilla orchids are also fairly tolerant of cool weather. You can leave all of these outdoors as the temperature begins to descend, at least for a period of time. This will send them into dormancy, or rest, to prepare for flowering. A few weeks of temperatures in the range of 60s (~16°C) during the day and 40s (~4°C) at night is what they need to initiate blooming. A decrease in daylight hours is often necessary, as well.
There are other species considered hardy. They tolerate a frost. It’s uncommon to find these for purchase in most places. They include Epipactis, Orchis, Spiranthes, Platantherea, Calanthes, Calopoghon, Bletilla, Pleione, Cypripedium, and Pogonia. Sometimes, you can find these online or from breeders, but it’s unusual.
Reduce Watering

Watering orchids is a tricky subject because it is easy to overwater them. This is even more true of those you keep indoors. Because water evaporates faster outdoors, you can and should water those more frequently. When you bring them indoors, you’ll want to cut back.
There is also the factor of dormancy to consider. Orchids take a rest during the winter months, often in preparation for flowering. During this time, they do not take in as much water and nutrients. If you water too frequently, you’ll end up with consistently soggy roots and potting medium.
Why is this a bad thing? Well, most orchids are epiphytic. They are, essentially, air plants. They grow on trees non-parasitically, taking in water and nutrients through moisture (rain and humidity) by way of their roots. The exposed roots get a lot of air circulation, so they dry quickly, and there is no decaying matter around them to introduce fungus or bacteria.
When we pot them, we use a bark-based potting mix. While this drains much better than ordinary potting soil, there is still a risk of it remaining wet, especially indoors and in the winter. Ease off of your watering routine for the cooler months. If you’re used to watering once weekly, cut that in half.
Cut or Reduce Fertilizing

In the same way that they take in less water while at rest, your orchids will also absorb fewer nutrients. In general, these plants are heavy feeders. During their growing phases, you can fertilize every two weeks, and they will thank you for it.
Once they enter their dormant period, that changes. They will stop taking in those nutrients, and instead, they will build up on the roots and the potting mix. This typically leads to root burn. This can manifest as a wilted plant with droopy leaves and brown tips.
If you’ve been fertilizing this winter, give it a rest. But if you think you’ve done some damage, there are signs to look for. If you see a whitish buildup on the potting medium or roots, this is excess minerals from the fertilizer.
There are two solutions to this issue. You can attempt to flush out the excess by running clean water through the pot. In many cases, this will suffice. You can also re-pot if you want to make certain you get all that buildup out of there. Rinse the roots thoroughly, and pot it with a new, clean potting mix.
Provide Enough Light

Here is the catch to your care during orchid winter dormancy. You should cut back on water and fertilizer, but if you want them to bloom, they need 12-14 hours of indirect light per day through the winter. With a reduction in daylight hours, in general, this can be a challenge.
Here is where orchids can be a bit high maintenance in the winter. On one hand, you may need to move them closer to the window to get the light they need. On the other hand, you’ll want to move them away from the window on cold nights.
While your plants won’t die if you let the amount of exposure wane with the natural cycles, you may not get many flowers. Most are spring bloomers and need that light to keep developing their buds during the cooler months.
Up the Humidity

If you’ve been a successful orchid owner for a minute, you already know that these epiphytes need substantial moisture in the air if you want them to perform. Most orchids are tropical rainforest dwellers. Some live in the understory, while others live high up in cloud forests. Either way, they get a lot of humidity in their native environments.
The amount of humidity a particular species requires varies. Phalaenopsis typically performs well at between 40-50%. That’s part of what makes them so popular: they are easy to care for indoors. Others like Vandas, for example, need at least 60%, if not higher, to survive.
I recommend not troubling yourself with a Vanda unless you have a well-lit window in your shower, a greenhouse, or live in a tropical climate. They’re gorgeous, but they need a lot of light and a ton of humidity.
For most species, aim for a range of 50-60% humidity. Most of them fall into this range, either at the top or bottom of their personal range. So, is this of particular concern in the winter? It is, for good reason, and one you might not think of.
In the winter, the air is dryer in general. There is less precipitation in most places, and the cold air can’t hold as much water vapor as warm air can. Then factor in you running your heater in the house. This contributes to further drying out the indoor air. You may notice that your skin is dryer in the winter. This is why!
So, it’s important to add moisture to the air in your home in the winter. It’s important to do it consistently. If you’re dealing with a single orchid, or maybe two, it’s not difficult to handle. You can use a pebble tray for these.
If you, like myself, have a veritable forest of tropical houseplants, I highly recommend a humidifier. Placing them in a brightly lit bathroom where you take frequent showers is typically fine as well. I rotate a humidifier between the two rooms where my plants live for the winter. Every other day, they get a dose of moisture in the air, and this seems to keep them all pretty happy.
A note on pebble trays: In case you’re unfamiliar with this practice, it’s a simple way to raise the humidity in a small area. You take a dish or tray and cover it with pebbles. River rock gravel works well. Then, fill it with water, but not over the pebbles, just below the top. This way, the pot doesn’t sit in the water, and you don’t risk root rot.
As the water evaporates, it increases the moisture in the air just above it. Which should be just around that plant. If you’re wondering if misting is worthwhile, it’s typically not. You’d have to lightly mist your plant several times a day to give it what it needs.
Keep the Air Moving

Finally, make sure that you keep the air circulating around your orchids. Fungus and mold grow best in cool, humid, still air. If your house is cool because it’s winter, and you’re adding humidity to the air, you need to make sure to move the air around.
If you have ceiling fans, winter is actually a good time to use them. Hot air rises, so your ceiling fans circulate that warmer air down near the living space. If not, a simple fan or air purifier is typically enough. I use air purifiers because why not kill two birds with one stone? A small oscillating or stationary desktop fan works, too. In the bathroom, just keep your exhaust fan going.
This is another step in preventing the dreaded root rot. Root rot is the bane of an orchid’s existence. A combination of moisture, cool temperatures, and still air is the perfect recipe for decaying organisms to set to work on that orchid bark, which can mean death to your beautiful, tropical plant.
Final Thoughts
To sum things up, you want to allow your orchids to rest over the winter. They need that dormancy to store up energy for their big spring bloom. You also want to control their environment to keep them warm, keep it humid, and, by all means, keep things moving. If you can achieve these conditions, your orchid should be in good blooming shape in just a few months!