As the days shorten and nights turn crisp, many orchid owners assume it’s time for their plants to slow down. In reality, fall is one of the most important seasons in an orchid’s year. The changes happening right now (shorter days, cooler evenings, softer light) are exactly the signals many orchids, phalaenopsis and cymbidiums in particular, need to start producing flower spikes. A few simple adjustments over the next several weeks can be the difference between a bare plant in January and a windowsill full of blooms.

Here’s how to help your orchids make the most of the season.

Let Your Orchids Feel the Temperature Drop

For the popular Phalaenopsis (moth orchid), a noticeable dip in nighttime temperature is the main trigger for a new flower spike. Aim for nights in the mid 50s to low 60s°F, roughly 10 to 15 degrees cooler than daytime, for three to four weeks. A spot near a window, away from heating vents, usually does the trick naturally.

Cymbidiums are even more dependent on cool fall nights. If yours spent the summer outdoors, you can often leave them out until nights approach the low 40s. That chill is what sets their buds.

Bring Outdoor Orchids In at the Right Time

If your orchids summered on a patio or porch, plan to move most of them indoors before nights consistently fall below about 50°F. Cattleyas, Oncidiums, and Phalaenopsis all appreciate cool nights but don’t like a true cold snap.

Before bringing plants inside, take a few minutes to inspect them. Check leaves, pseudobulbs, and the undersides of pots for insects like mealybugs, scale, or slugs. A gentle rinse and a close look now can keep hitchhikers from spreading to the rest of your collection.

Give Them More Light, Not Less

As the sun sits lower in the sky, window light gets weaker and shorter. Orchids that were perfectly happy a few feet from a window in July may need to move right up to the glass in October. South- and east-facing windows are ideal this time of year.

Watch the leaves for cues. Healthy Phalaenopsis leaves should be a medium, grassy green. If they turn dark forest green, your plant probably wants more light.

Water Less Often

Cooler temperatures and shorter days mean slower growth and slower evaporation, so your orchids will need water less frequently than they did in summer. Overwatering is the most common cause of root rot in fall and winter.

The best rule of thumb: water when the potting medium is nearly dry, not on a fixed schedule. Stick a finger or a wooden skewer into the mix. If it comes out damp, wait a few more days. Always water in the morning so leaves and crowns can dry before the cooler night.

Watch Humidity as the Heat Turns On

Once your furnace kicks in, indoor humidity can drop fast, and orchids notice. Most prefer humidity between 40 and 60 percent. To boost moisture around your plants, try setting pots on a humidity tray filled with pebbles and water (keeping the pot above the waterline), grouping plants together, or running a small humidifier nearby.

Ease Up on Fertilizer

With growth slowing, your orchids don’t need as much food. Switch to feeding about half as often as you did in summer, and use a diluted, balanced orchid fertilizer. Flush the pot with plain water once a month to prevent salt buildup around the roots.

A few types, such as Dendrobium nobile hybrids, catasetum, and Cyrtopodium, actually prefer a cool, drier rest with little or no fertilizer in fall. That rest period is what encourages them to bloom in late winter.

Spot the Spike and Protect It

Keep an eye out over the coming weeks. A new Phalaenopsis flower spike usually emerges from between the lower leaves and looks like a small, mitten-shaped green or silvery root tip. Once you see one, avoid moving or rotating the plant too much, since the spike grows toward the light and changing its direction can cause twisted stems. When it’s a few inches tall, add a stake and clip it loosely as it grows.

Your Fall Orchid Checklist

To recap, this season you’ll want to: let nighttime temperatures drop 10 to 15 degrees, bring outdoor plants in before nights fall below 50°F, move orchids closer to the window, water only when the mix is nearly dry, add humidity once the heat is on, and cut back on fertilizer.

Grow Your Collection This Season

Fall is also a great time to add new orchids to your home. Plants that arrive now settle in just as their natural blooming cycle begins, giving you something to look forward to through the gray months ahead. Explore our selection of orchids, grown and shipped by Odom’s Orchids since 1962, and find your next favorite bloom.