Want a Thanksgiving Cactus Covered in Flowers? Do This One Job in September

Don't wait until the buds appear! This simple September job can help your Thanksgiving cactus bloom beautifully for the holidays...

Thanksgiving cactus in bloom
(Image credit: Elena Grishina/Getty Images)

If you want your Thanksgiving cactus to put on a spectacular display in November (and obviously you do!), then September is the month to start thinking about its blooms.

Yes, I know; it feels far too early to worry about a plant that won't flower for months, but what you do now can make a big difference to how many buds your Thanksgiving cactus produces. And fortunately, the most important job is surprisingly simple: make sure your plant gets a good night's sleep.

What do I mean by this? Well, the Thanksgiving cactus is a short-day plant, meaning it needs longer nights to encourage flower-bud formation. And, as the days naturally begin to shorten in September, your plant is approaching the conditions it needs to bloom... but even a little artificial light at the wrong time can interfere with that process.

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The One Thing Your Thanksgiving Cactus Needs In September

When it comes to getting a good night's kip, we can all agree that we sleep sounder under the comforting gloom of a blackout blind. Your Thanksgiving cactus (or Christmas cactus, actually!) are the same: they crave that natural dark after the sun dips below the horizon.

This means, then, that if yours is sitting on a windowsill in a room where the lights are regularly switched on after dark, it's time to consider moving it somewhere where it can experience natural darkness in the evening.

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Now, before you get carried away, you don't need to put it in a closet or make its care complicated. A room that isn't regularly lit at night is usually enough for your Thanksgiving cactus, so long as you keep it consistent.

The aim is to give your Thanksgiving cactus around 12 to 14 hours of uninterrupted darkness each night as fall approaches, while keeping it in bright (but indirect) light during the day.

A spare room, guest bedroom, or another naturally darkened room can work really well; the trick is to just avoid somewhere that becomes completely dark during the daytime, since the plant still needs plenty of light to grow and prepare for flowering.

Thanksgiving cactus – or Schlumbergera truncata – with pink flowers

(Image credit: Getty Images)

It's important you don't skip this step in September, as a Thanksgiving cactus doesn't suddenly decide to bloom when Thanksgiving arrives; the process starts several weeks earlier, when the plant responds to changes in day length and temperature by beginning to form flower buds.

That means this month is a useful one for checking where your plant is growing and what kind of light it receives after sunset. And, if it's beside a lamp, under a kitchen light, or in a room where the lights stay on late into the evening, making that small change now? It could be the difference between a bright and beautiful display at your Thanksgiving table, and a seriously lacklustre one.

Don't leave it too late; once your Thanksgiving cactus is entering its bud-setting period, you'll want to avoid constantly moving the plant between rooms or changing its light exposure from day to day. Sudden changes in temperature, light, or watering can cause stress, and Thanksgiving cactus may drop developing buds if conditions change dramatically.

Thanksgiving cactus – or Schlumbergera truncata – with white and pink flowers

(Image credit: Alamy)

The one thing to do for your Thanksgiving cactus in September, then? Find a good spot with bright, indirect daytime light and reliable darkness at night, then leave it there.

With the right conditions in September and October, those unassuming green segments can and will eventually become covered with the colorful flowers that make Thanksgiving cactus such a bodacious houseplant to have on display over the holiday season.

Just be sure to water when the top portion of the potting mix has dried rather than keeping the soil constantly wet, and you're all but guaranteed a good show by the time November rolls around. Good luck!

Kayleigh Dray
Content Editor

Kayleigh is an enthusiastic (sometimes too enthusiastic!) gardener and has worked in media for over a decade. She previously served as digital editor at Stylist magazine, and has written extensively for Ideal Home, Woman & Home, Homes & Gardens, and a handful of other titles. Kayleigh is passionate about wildlife-friendly gardening, and recently cancelled her weekend plans to build a mini pond when her toddler found a frog living in their water barrel. As such, her garden – designed around the stunning magnolia tree at its centre – is filled to the brim with pollinator-friendly blooms, homemade bird feeders, and old logs for insects to nest in.