The Christmas cactus is one of the most popular festive houseplants, but despite its name, it’s particularly vulnerable to one silent killer at this time of the year: central heating.
Hot radiators and centrally heated rooms are the underlying causes of so many Christmas cactus problems – and thanks to the chillier weather outside, they're an even bigger issue right now. Luckily, though, the symptoms are pretty obvious.
Below, you’ll find out how central heating affects a Christmas cactus, the signs it’s struggling, and a few ways to keep your plant as healthy as possible over the winter months.
What you'll need
- A Christmas cactus plant, like this red-flowered Schlumbergera, £11.69 at Crocus
- A humidifier, like this plant humidifier, £13.99 at Amazon
- Or, a shallow tray like this £6 Verve tray from B&Q, filled with pebbles like these premium clay pebbles for plants, £6.99 at Amazon
- Houseplant feed, like the Westland Cacti and Succulent Feed Concentrate, £2.59 at Amazon
How can central heating affect a Christmas cactus?
I thought we’d start by looking at exactly how central heating can affect a Christmas cactus. If you’ve noticed the buds falling off your Christmas cactus, your indoor heating system could be to blame.
‘Central heating can dry out Christmas cacti and make them lose moisture fast,’ warns Andy Little, houseplant buyer at British Garden Centres. ‘This causes the leaves to go limp, shrivel, and sometimes turn brown or red. The flower buds may fall off before opening, too.’
So, besides colour changes and bud loss, a Christmas cactus will drop its leaves when it’s under stress from indoor heating. If you want your Christmas cactus to flower, it’s crucial that you keep it well away from hot radiators.
The plant’s surprising origins have a lot to do with its resistance to artificial heat.
‘Despite its name, Christmas cacti actually originate from tropical rainforests, so they tend to like a more humid environment,’ explains Asta Foufas, floristry lead at Arena Flowers. ‘This can be difficult to maintain in the average British home, especially in winter when we have the central heating and radiators blasting out heat and lowering humidity.’
Luckily, there are a few ways to protect your Christmas cactus from the worst effects of central heating…
How to protect a Christmas cactus from central heating
If you’re afraid that your Christmas cactus is at risk from central heating, the first thing you need to do is move it to a cooler spot. In fact, choosing the right place for your plant is one of the most important parts of caring for a Christmas cactus properly.
‘Move the cactus away from hot radiators and direct sunlight to a cooler spot with bright, indirect light,’ advises Andy from British Garden Centres.
Temperature consistency is key: most houseplants hate spots where it’s cold one moment and hot the next, so make sure your Christmas cactus is far away from heaters, radiators and draughty areas.
Asta already mentioned that Christmas cacti love a moist environment, so it’s worth looking at ways to boost humidity levels, too.
‘Misting plants in winter can also be beneficial, and you could also try placing your plant in a shallow tray of moist pebbles to increase the humidity in the surrounding air,’ Asta suggests. You can buy clay pebbles for plants from Amazon to line a shallow tray, or even buy a plant humidifier from Amazon.
It can be tempting to water your Christmas cactus more to compensate for the drier environment, but overwatering can actually do your plant more harm than good.
‘Watering too much to fix the dryness can harm the roots,’ warns Andy. ‘Water only when the soil on top feels dry, and make sure excess water drains away.’
If you’ve already overwatered your plant, it’s worth repotting the Christmas cactus with fresh, well-draining soil like the Westland Houseplant Potting Mix from Amazon.
Christmas cacti make some of the very best Christmas houseplants for vibrant blooms over the winter months. Keep them away from radiators and heaters, and water them properly, and you should see a colourful display every year.
