Knowing how to propagate Christmas cactus successfully does require some careful prep, though. You will also need to know when to water your Christmas cactus, too, to ensure water remains fresh and the levels sufficient. As Homes & Gardens’ garden editor, I’m a big fan of indoor plants, and love growing a Christmas cactus, but hadn’t rooted them in water before. So, I asked plant expert Vladan Nikolic, the founder of Mr. Houseplant LLC (opens in new tab) for his expertise. This is what he advises.
Will a Christmas cactus root in water?
‘Yes, a Christmas Cactus can root in water,’ affirms Vlandan. ‘The reason why cacti can root in water but die in overwatered soil is because of oxygen availability. Roots need oxygen, and it’s easily available in water. ‘In soil, however, there is a lot of competition for oxygen. Besides roots, there are many bacteria and fungi that use the oxygen. Water generally doesn’t contain as many bacteria and fungi as soil, so the competition for oxygen is lower. ‘As the oxygen in soil is being used by these microorganisms, the amount of oxygen goes down, and a different type of bacteria and fungi start developing – anaerobic bacteria.’ This type of bacteria can lead to root rot and eventually kill your plant, so rooting in water is a great option.
How to root a Christmas cactus in water
As Vladan says, and I have since discovered, rooting Christmas cactus in water is easy. All you need is a small, sharp knife and a small glass vase (it doesn’t have to be glass, but I like to see the roots form in the water; a cup will do!). Then follow these steps.
1. Trim the stem of the Christmas cactus cutting
Use your knife to take a Y-shaped cutting that has a minimum of two segments.
2. Prep the vase
Next, put pebbles or small, round stones into your vase in a layer around 2in deep, then cover with water. Add the cutting to the vase so that only the cut tip to two nodes down are in the water. If you submerge your plant too much it won’t root healthily. Place your vase in a bright (but not sun-scorched) spot.
3. Monitor water levels
The water will be drunk by the cutting and will evaporate in a heated room, so do keep an eye on it, topping it up with fresh water as necessary. Also ensure the water stays healthy; if it starts to develop algae, refresh it. Next, you can move on to repotting your Christmas cactus, or you can continue to grow it in water, though you may need to swap it to a larger container as it grows.
4. Be ready to pot up your cutting
You can repot your Christmas cactus once roots have formed that are as long as the cutting itself. This can take between three and six weeks. Put the cuttings into a good quality potting mix, combined with a little compost and sand.
Is it better to propagate Christmas cactus in soil or water?
It all comes down to personal preference, as both methods have pros and cons. However, Vladan Nikolic, the founder of Mr. Houseplant LLC, suggests that water propagation is easier for beginners because there is less to think about. You simply place the cutting in water and leave it to root. Though, he notes that this method can come with its downsides. This easy-to-care-for Christmas Cactus sits in a 6in container and measures 10-12in inches from the roots to the top leaves. It loves bright light and moist soil, and it will look great throughout the festive season. ‘The con is that the transition from water to soil might not be successful,’ he says. ‘If rooting in the soil, you’re already growing the plant in its long-term environment, there is no adjustment necessary. However, it is more difficult, as it requires proper watering and potting mix, so it requires a bit of skill.’
How long does it take a Christmas cactus to root in water?
Your Christmas cactus should root after two to three weeks, though, it can take longer in some cases, and it won’t be ready for repotting for some six weeks, when the roots are as long as the cutting.
