When I first started growing my Christmas cactus, I had problems with its flowering, which I later found out was because I was underwatering my plant.
I had made the classic mistake of misinterpreting that because it was a cactus, it did not need much water.
Since then, I have done lots of research, and I even grew Christmas cacti commercially in the garden where I work and through first-hand experience, I’ve learned all the tips and tricks to water Christmas cacti so that they meet their watering requirements and support flowering.
In this article, I’ll share with you all the techniques and methods that I learned for watering in a step-by-step guide so you know exactly what to do…
Not much time to spare? Let’s get straight to the point!
Christmas cactus is native to rainforests rather than deserts and requires watering so that the soil is evenly moist. Water the Christmas cactus with a good soak once per week and mist the leaves twice per week to recreate the optimal watering cycle and humidity of the Christmas cactus native environment.
Christmas cacti are very unusual for cacti in that they are adapted to rainforests rather than deserts, which means they prefer more frequent watering, less sun, and higher levels of humidity compared to most cacti.
Keep reading for how often and how much to water Christmas cacti in your home for the optimal balance of moisture so that it thrives…
How Often to Water Christmas Cactus
So, for us to understand how to water our Christmas cactus, I think we need to appreciate how they grow in the wild…
Christmas Cactus (Schlumbergera) is a type of cactus that grows in cool, mountainous forests in Brazil in shaded areas with high humidity and relatively frequent rainfall.
This environment is in stark contrast to that of most cacti, which tend to thrive in dry, arid, sunny areas.
Therefore, one of the most frequent problems with growing Christmas cacti is usually not watering often enough as they are adapted to cool humid conditions unlike their desert-dwelling counterparts.
It’s a classic mistake that I made myself!
To grow Christmas cactus successfully in your home, we need to simulate some of the watering and humidity conditions of its native habitat.
Christmas cactus requires higher humidity then most house plants.
It is important to note that whilst I water my Christmas cactus once a week in my current flat (in New York), I had to water every 3-5 days when I lived in a much dryer climate in California.
This point illustrates that universal watering advice is, in my opinion, rather redundant as watering frequency depends on several factors.
However, there is a way to tell when your plant needs watering regardless of climate…
The method for watering that I was taught by commercial growers was that the soil should feel evenly moist for most of the week, but the top inch of soil should dry slightly before the next bout of watering.
Once you establish how quickly it takes for the top inch of the soil to dry out in your home then you can establish a watering frequency that is tailored to your conditions.
I have found that Christmas cactus is also somewhat more drought tolerant than most houseplants and can go 2 weeks without watering as long as it is not in an air current or if the air isn’t too dry, so it is forgiving if you miss the odd watering.
There are several factors that we need to be aware of that can cause your Christmas cactus to dry out faster or slower in the home due to:
- The humidity and temperature of your home (houses are often low in humidity, which is contrary to Christmas cactus’ preference for high humidity).
- The size of the pot or container (smaller pots dry out quickly).
- The material of the pot (clay and terracotta are breathable, whereas plastic and ceramic retain moisture).
- Whether the cactus is near a source of heat or in the current of air-con or forced air (which saps moisture from the leaves and dries the soil).
- The capacity of the soil to retain moisture (Christmas cactus requires moist yet well-draining soil).
All of these factors influence the speed of the soil drying out, but the method of feeling the soil can help you keep the right watering schedule regardless of how man variables there are to consider.
How I Increase The Humidity…
So, the traditional advice that I read online from other sources was to mist the leaves (which are actually modified stems) of your Christmas cactus to increase the humidity.
I found this effective when I lived in the Pacific Northwest, which has a more temperate climate. I misted the leaves twice a week, and my Christmas cactus was happy.
However, I have also lived in California and New York, as I mentioned. California had naturally low humidity, and in New York, I had to use a lot of indoor heating in the Winter, which created an environment so dry that my Christmas cactus began to wilt, regardless of how often I misted.
So, I tested several different methods of increasing the humidity…I experimented with growing it in:
- I located one in the bathroom for a boost in natural humidity.
- I grouped my houseplants near each other, and I filled a tray with water, propping the cactus out of the water with pebbles (the idea is that consistent humidity from the water increases the humidity).
- I tried a humidifier that I bought online.
I found that the tray of water and pebbles trick worked well most of the time, but it couldn’t counteract the very dry air in the Winter when I had to use a radiator, and my plant began to wilt.
The cactus in the bathroom grew very well, but I noticed it didn’t like the cold blasts of air when I opened the window to air the room out, and the flower buds would drop, so this is not always a good option.
What worked the best was using a humidifier, as you can set the humidity precisely, and I found it more convenient than misting regularly. When I used the humidifier, my plant looked the best, flower well, and didn’t wilt, so in my opinion, a humidifier is the best option for increasing the humidity.
Remember that Christmas cactus prefers indirect light rather than full sun. Too much sun would burn the leaves and cause the cactus to lose too much moisture.
How to Tell if the Christmas Cactus is Overwatered or Underwatered…
I’ve observed that the cactus can shrivel and droop in response to over- or underwatering, so the only way to distinguish the cause is to feel the soil.
If it is dry both at the surface and at the base of the pot (I feel the soil at the base through the drainage hole), then the cactus is suffering from underwatering.
In this scenario, I recommend Increasing the frequency of your watering if your soil is drying out quickly over the course of 7 days so that the soil is more consistently moist rather than dry.
I would mist the under-watered cactus more regularly (or use a humidifier as discussed) to increase the humidity and reduce water loss through the leaves.
If the soil feels damp or even saturated, then I would check that nothing is blocking the drainage hole and empty any water that may be in a tray or saucer used underneath the pot.
Overwatering or damp soil can prevent the cactus from growing and blooming properly and even cause root rot, so it is important to scale back the watering and ensure good soil drainage.
(For more information, read my article Why is my Christmas cactus wilting?)
How Much to Water a Christmas Cactus
Knowing how much water to use is vital to the success of your Christmas Cactus.
Whilst the variability of the climate, temperature, air currents, etc. can all influence how often you water your plant, how much water you use when watering Christmas cactus should stay the same.
I always water the Christmas cactus with a generous soak so that excess water trickles out of the base of the pot.
I do this because watering with a good soak ensures that the water infiltrates properly and reaches the roots of your Christmas cactus so it can uptake the moisture it requires.
A generous soak also encourages the roots to grow and establish in the potting soil.
Avoid this classic mistake! Watering too lightly only moistens the top inch or so of the soil which can cause the roots to grow shallow or prevent the roots from reaching the water altogether, causing drought.
Watering with a good soak and misting regularly helps to replicate the natural watering cycle and level of humidity to which the Christmas cactus is accustomed.
I have experimented with a few ways of watering, and I’ve found it is better if I water my Christmas cactus with a generous soak from the top and then Ileave water to collect in the tray underneath my pot for 30 minutes.
I found that If I leave my plant sitting in water for half an hour, the soil medium usually draws up all the moisture through the drainage holes in the base of the pot, which ensures the potting soil is evenly moist.
I first did this when I noticed my friend’s Christmas cactus was suffering from underwatering because the potting soil was repelling moisture off the surface and not absorbing it properly therefore, it needed to sit in water to give the soil time to draw up the moisture,
This combination of watering from the top and allowing water to absorb through the bottom is the method that I found works best for watering Christmas cactus.
Pro Tip: I pick up my cactus pot regularly to assess the weight. Once the cactus feels noticeably lighter, I know the soil is drying, and my cactus needs watering.
(If your Christmas cactus is dropping buds, read my article for more information)
Well-Draining Soil Maintains an Optimal Balance of Moisture
I learned from the experts that good watering practices should be in conjunction with the right sort of well-draining yet moisture-retentive potting mix to keep Christmas cacti healthy so that the soil can stay moist but not damp to avoid root rot.
Whilst I was working at the garden center I asked some of the commerical growers about thhe best potting mix for crhistmas cacti. The taught me that they mix 3 parts potting soil with 1 part horticultural sand or grit to ensure the soil can retain moisture yet allow excess water to drain away from the roots.
Christmas cactus is an epiphyte like many cacti which means it derives a lot of moisture and nutrients from the air which is why it prefers humidity and porous soil.
With well-draining soil yet moisture-retaining soil, you can provide enough moisture to meet the plant’s requirements without causing root rot.
(Read my article, how to revive a dying Christmas cactus).
Plant Christmas Cactus in Pots with Drainage Holes
I know this may seem obvious to a lot of people, but I have a lot of beginner indoor gardeners come to me with houseplants dying due to the plant being potted in a pot with drainage holes and the roots sitting in boogy soil, so I think it is worth mentioning…
Whilst Christmas cacti prefer moist and humid conditions, they dislike their roots being sat in water for any length of time.
Your pot or container must have drainage holes in the base to allow excess water to escape from the bottom of the pot.
Watering so that water trickles from the base of the pot is also a good way to ensure you have used enough water to infiltrate the soil and reach the roots of your Christmas cactus.
If your cactus is planted in pots or containers without drainage holes in the base, water will pool around the roots, causing root rot, and the plant will die back.
It should also be noted that from research and first-hand experience, Christmas cactus prefers smaller pots and is somewhat root-bound as this promotes flowering.
(There are several reasons for not flowering, so if your Christmas cactus isn’t blooming read my article for the solutions.)
We should consider that water can still pool around the roots and cause root rot if:
- The drainage holes become blocked up due to compacted soil or roots. If you notice the soil draining slowly, then check to ensure that water can escape freely from the base.
- A saucer and trays are underneath the pots or containers. Christmas cactus requires well-draining soil. Saucers and trays are often used to prevent water from spilling in the home. Empty the saucer or tray after 30 minutes to ensure water does not pool around the roots indefinitely.
- Decorative outer pots. Christmas cacti are often sold in stores and presented in decorative outer pots that do not have drainage holes. Ensure that you empty the pot regularly to prevent root rot or just plant Christmas cactus in a pot with drainage holes in their base.
Do you have any tricks and tips that you use for watering Christmas cacti? If so, please leave a comment below, as I’d love to hear them all!!
Key Takeaways:
- Water Christmas cactus with a generous soak once per week and mist the leaves twice per week to create the optimal balance of moisture. Christmas cactus is native to rainforest and requires more watering and humidity than most species of cactus.
- Always water with a generous soak to ensure water reaches the Christmas cactus roots.
- Plant Christmas cactus in well-draining soil that retains some moisture yet allows excess water to escape to allow the plant to uptake the moisture it requires and also prevent root rot.
- Christmas cactus should be planted in a pot with drainage holes in the base. Empty saucers and trays regularly to prevent the soil from staying damp and promoting root rot.