Don’t listen to anyone who tells you to give your Christmas cactus sugar water – use this type of fertiliser instead for long-lasting blooms

I’m all for a handy houseplant hack, but do Christmas cacti like sugar water? Really?

If you want your Christmas cactus to bloom for a long time, you’ll want to steer clear of this one. Feeding the plant sugar water can play host to a number of Christmas cactus problems, and it can even ruin the festive blooms altogether.

Here’s why Christmas cacti absolutely don’t like sugar water – and what to feed them instead, if you want plenty of blooms over the next month or two.

Do Christmas cacti like sugar water?

Sugar water is sometimes recommended as a quick hack for encouraging more Christmas cactus blooms. It might be an expert-approved ingredient in butterfly food, but for Christmas cacti, it’s another story – and actually, feeding your plant sugar water can do more harm than good.

‘It’s not recommended to use sugar water on Christmas cacti, as it can stop the plant from absorbing important nutrients,’ warns Asta Foufas, floristry lead at ethical flower retailer Arena Flowers.

It’s all down to the moisture balance in the soil, which sugar water can very quickly disrupt.

‘Sugar changes the way water moves through the soil, making it harder for the roots to take up what they need,’ explains Jo Lambell, founder of houseplant retailer Beards & Daisies.

Sugar water can also draw moisture out of the plant’s root cells, Jo adds, leading to limp pads and fewer buds. The last thing you want is to be googling how to perk up a droopy Christmas cactus at this time of the year, so it's best to put this questionable Christmas cactus care tip to bed.

Beyond the impact on the plant itself, sugar water can attract a host of other problems.

‘Sugar water is not good for Christmas cacti as it can cause mould or attract pests,’ says Andy Little, houseplant buyer at British Garden Centres.

Plus, there’s just no substantial benefit to feeding your Christmas cactus sugar water in the first place.

‘Christmas cacti can’t use sugar in a way that meaningfully supports growth or flowering,’ says Jo.

A Christmas cactus is one of the longest-flowering Christmas houseplants, but using sugar water can forfeit the blooms.

If you know how often to water a Christmas cactus, and keep it in a spot with a consistent temperature, that’s a good start – but if you’re keen to promote even more blooms, it’s wise to get your hands on a good fertiliser…

The best fertiliser for a Christmas cactus

Now that we’ve established that Christmas cacti don’t like sugar water, we can look for a fertiliser that actually will give the blooms a boost.

‘Use a balanced fertiliser made for houseplants or cacti during the growing season,’ says Andy from British Garden Centres. Westland Cacti & Succulent Feed Concentrate, £2.59, is Amazon's choice for cacti fertilisers.

So, which ingredients should we be looking for?

‘Go for a balanced, water-soluble houseplant fertiliser,’ advises Jo from Beards & Daisies. ‘Something gentle and even, such as a 10-10-10 or 20-20-20 formula, works well.

‘Look for magnesium, iron and manganese on the label; these help maintain healthy colour and steady growth.’

Baby Bio Houseplant Feed, which you can grab for just £1.99 at Amazon, is a balanced, highly-rated fertiliser.

It’s important to know when to stop feeding indoor plants before winter arrives, and the same goes for Christmas cacti.

‘Feed lightly,’ says Jo. ‘Dilute to half strength and use every two to four weeks from spring to late summer, then pause feeding in early autumn to help with bud formation.’

Jo even recommends orchid feed as a good alternative, thanks to its low, steady nutrient levels, which are perfect for a Christmas cactus’s sensitive roots. Westland Orchid Feed Concentrate, £2.59 at Amazon, is a good choice.

Avoid giving your Christmas cactus sugar water and stick to a balanced houseplant feed, and your plant will stand the best chance of flowering success.