Why is my Christmas cactus not blooming? Experts suggest the likely cause – and a speedy solution

Many plants are synonymous with Christmas – whether that is holly, poinsettia, or timeless mistletoe. However, a rising interest in the aptly-named Christmas cactus suggests there is room for a new festive staple with (dare we say) even more character.

As we approach the holiday, there is an inevitable interest in increasingly-popular houseplants – and it's possible that knowing how to make a Christmas cactus bloom is on your agenda for the coming weeks.

If you've read up on how to grow a Christmas cactus, you likely will have heard that carting for the plant of the moment is relatively easy. 

However, a healthy Christmas cactus is certainly no guarantee, and so, if you question, 'why is my Christmas cactus not blooming?', this is most likely what you're getting wrong, and what to do.

Why is my Christmas Cactus not blooming?

'If your Christmas Cactus is not blooming, then it's most probably because you are not giving it enough water or because the humidity around the plant is too low,' says Diana Cox from The Gardening Talk. 

As the expert explains, the plant is native to rainforests and requires a humid environment and soil that is moist but not overly soggy. 

However, the potential problems don't end there. 'Low temperatures, excess sun exposure, and fertilizer surplus can also cause Christmas cactus to stop blooming,' Diana says. And Stacie Hiett, a Texas-based expert from Counting Tomatoes, agrees.

'The holiday cactus is a short-day bloomer, which means it sets blooms when exposed to longer night time hours and cooler temperatures,' she says.

'Approximately six to eight weeks are needed for buds to form. If you have a Thanksgiving cactus, start the reduced light hours around the early part of October; if you have a Christmas cactus, start the reduced light hours around mid-October. The Easter cactus takes a bit longer to form buds; start the process for blooms approximately 14 weeks before Easter.'

How to fix a Christmas cactus that's not blooming

As the experts suggest, knowing when to water a Christmas cactus is one of the most impactful things you can do. 'If your Christmas cactus is not blooming, you should check if the soil is wet. If this is the case, you should immediately water your plant,' Diana emphasizes. 

But the process continues beyond your watering habits.

'If you find that the plant is not underwatered, you should use a hygrometer to check the humidity. If the hygrometer indicates that the humidity is below 50 percent, you should use a humidifier in order to help increase the humidity around your plant,' she says. This is Amazon's best-selling, top rated hygrometer.

'Additionally, you should make sure that the temperature is around 60°F (16°C). Christmas cacti will grow best and bloom when the temperature is between 60 and 70°F (16 and 21°C).

When should you put a Christmas Cactus in the dark?

There is a common belief that putting your cactus in a dark closet for 14 hours a night will help it bloom. However, if you want to see flowers before Christmas, it is, unfortunately (probably) too late. 

'If you want your Christmas cactus to start blooming, you should put it in the dark at the beginning of October for 12 hours a day,' Diana says. 'If you keep doing so for at least eight days, your Christmas cactus will start blooming.'

If you know how to propagate a Christmas cactus, though, you can enjoy these benefits year-on-year – because we expect this plant trend isn't going anywhere fast.