Christmas cacti are one of my favorite houseplants as they reliably (as the name suggests!) display gorgeous flowers in the Winter. However, I commonly encounter people (in my job as a commercial supplier to garden centers) who tell me their Christmas cactus is dying.
Therefore, I have lots of experience reviving these plants back to full health, and I have included all my methods and tips in this article so you can save your Christmas cacti, too…
Overwatering and cold temperatures result in a wilting Christmas Cactus with dropping leaves. Christmas cacti need the first 2 inches of the soil to dry out between bouts of watering. If the soil is consistently damp, the stems droop, fall apart and die back due to root rot.
Summary of reasons I encounter for a dying Christmas cactus…
|Symptoms of a Dying Christmas Cactus:
|Reason for a Dying Christmas Cactus:
|Christmas Cactus Wilting:
|Overwatering, slow draining or compacted soils, underwatering, low humidity, and temperatures below 50ºF (10ºC).
|Christmas cactus is dropping leaves (stems):
|Consistently damp soil from overwatering is the biggest factor, along with cold temperatures. Compacted soils also slow drainage and cause the leaves (stems to drop.
|Christmas cactus turning red or purple :
|There is too much direct sunlight (Christmas cacti need bright, indirect light).
|Christmas cactus leaves (stems) turning yellow:
|Overwatering or a lack of nutrients. Watering too lightly and hydrophobic soil also causes yellowing stems.
To revive your dying Christmas cactus, it is important to recreate some of the conditions of its native environment by increasing the humidity with regular misting, allowing the first 2 inches of potting soil to dry between each watering, and locating the cacti in bright indirect light.
Keep reading for my step-by-step process for saving a dying Christmas cactus…
Why is My Christmas Cactus Wilting and Leaves (and Stems) Dropping? (Overwatering and Underwatering)
- Symptoms. Stems droop, and sections of the stems randomly fall off. Sometimes, the stems also turn yellow.
- Causes. Usually, stress is due to overwatering, slow-draining boggy soils. Underwatering, cold temperatures, and low humidity are contributing factors.
From my experience, wilting stems are the Christmas cacti’s are early warning signs that the cactus either does not have enough water or the soil is too damp due to overwatering and poor drainage.
Usually, I find the cause of wilting stems is overwatering. Christmas cactus grows on rocks or other trees in its native environment in Brazil and, therefore, has very good drainage around the roots. If the roots are sat in damp soil, the stems will wilt as a sign of stress.
Overwatering and compacted soils exclude oxygen from the soil around the Christmas cactus’s roots. Without enough oxygen, the roots cannot respire effectively, which interferes with their ability to draw up water and nutrients, resulting in a wilting Christmas cactus.
If the cactus is persistently damp soil for too long, then I see sections of the stem begin to fall off, and the remaining stems can turn yellow.
Christmas cactus do not have leaves but rather sections of flattened stems which are specialized to photosynthesize and function like leaves.
Sections of stem falling apart are also associated with unfavorably cold temperatures. Temperatures cooler than 50ºF (10ºC), combined with overwatering, tend to cause stem sections to fall off.
(Cold temperatures and sudden temperature fluctuations can also cause flower buds to fall off).
This happened to my Christmas cactus in Winter when it was kept on a window sill with some of the stems in contact with the glass.
The glass at night was significantly cooler than the room’s ambient temperature, which exacerbated the cold stress and caused some sections of the stem to fall off.
However, I discovered that wilting and dropping leaves can also be caused by low humidity.
The Christmas cactus is native to humid tropical Brazil. If the humidity is too low, then the cactus loses too much water from its stems, which causes it to wilt and for pieces to fall off.
This also happened to me when I lived in an apartment, and the air conditioner would dry the air too much for my Christmas cactus to tolerate.
How I Revive Wilting Christmas Cactus That is Dropping Leaves
The key to reviving a wilting Christmas cactus is to recreate some of the conditions of its natural habitat by watering when the soil is dry to the touch, maintaining the optimal temperature range, and increasing the humidity with regular misting.
- I would only water your Christmas cactus when the top inch of the soil feels dry to the touch. I use my finger to detect moisture to determine when the soil typically dries out and water accordingly. This watering balance ensures that the cactus’s watering requirements are fulfilled, allowing the soil to dry sufficiently to avoid wilting and root rot. (I think feeling the soil is more accurate than any moisture meter that I have tested).
- I mist the cactus’s stems regularly to recreate a humid microclimate that mimics the conditions of its native Brazilian rainforest environment. Misting creates optimal conditions for your Christmas cactus and prevents it from losing too much moisture through transpiration. I also recommend using a special plant humidifier (which is available online)e if you can’t mist your plant every day.
- When repotting Christmas cactus, my favorite potting mix is a mix of 2/3 potting soil and 1/3 inorganic material such as grit or perlite. A potting mix with grit or perlite helps to increase the porosity of the soil, allowing for water to drain efficiently and for oxygen to reach the roots for root respiration. This is another way I imitate the typical drainage conditions of the Christmas cactus’s native habitat.
- Keep your Christmas cactus in temperatures of ideally more than 50ºF (10ºC). The exact preferred temperature range of the Christmas cactus varies throughout the year according to seasonality, and the plant requires a specific sequence of temperatures as a prerequisite to flowering. keep the cactus away from cold, draughty areas of the house.
(Read my article, why is my Christmas cactus not flowering to learn more about how to increase the number of flowers).
I followed all these steps, and my Christmas cactus was revived from its wilting appearance and perked up in the next 3 weeks.
If some stem sections have fallen off, I use this as a great opportunity to propagate my Christmas cactus. Christmas cacti are very easy to propagate and grow relatively quickly in the right conditions.
Here is my photo of a section of Christmas cactus that fell off the original plant and was successfully rooted in a potting mix of approximately 60% soil and 40% horticultural sand. It has grown into an impressive plant after just two years of growing in the right conditions, even flowering significantly, to my delight!
A well cared for Christmas cactus can live for more than 100 years.
Why are My Christmas Cactus Leaves (stems) Turning Yellow?
- Symptoms. Yellowing leaves (stems) and a drooping appearance.
- Causes. A lack of nutrients or overwatering, underwatering, low humidity, and cold temperatures.
If a Christmas cactus is turning yellow, then this is usually your first warning sign that the roots are in potting soil that is too damp for it to tolerate.
The first signs of overwatering are typically drooping, however, the stems turn yellow if the overwatering problem persists for long enough, add in some other unfavorable growing conditions such as sudden temperature fluctuations and low humidity, and the yellow effect is often exacerbated.
In this case, you should follow my instructions detailed above pertaining to overwatering by allowing the top 2 inches of soil to dry between bouts of watering, ensuring the soil is well draining, and emptying any saucers, trays, or decorative outer pots of excess water which can pool around the base of the pot and keep the soil in a consistently damp state.
However, yellowing leaves can also be due to underwatering if you are watering too lightly or the potting soil has dried out completely, which can cause it to become hydrophobic and repel water off the surface of the soil without infiltrating properly.
My personal Christmas cactus turned yellow because it was in a pot that was too small. Christmas cacti can tolerate being pot-bound, which can even increase the chance of flowering, but I left mine in the same pot for around 5 years.
The roots were actually visible growing out of the soil as they were so desperate for more soil and space to grow. The roots had exhausted the available nutrients in the potting soil, and the cactus needed repotting and the occasional application of a general houseplant fertilizer.
How I Revived My Yellowing Christmas Cactus
- If your Christmas cactus has been in the same pot for many years (and roots are visibly growing out of the soil), it may be necessary to repot it to a pot one size up. Only re-pot The cactus into a pot one size up from its original pot, as over-potting tends to lead to root rot. Ideally, re-pot your Christmas cactus in the Spring, as this is when the plant is most resilient to stress. I advise using a potting mix of 60% potting soil and 40% grit or perlite.
- I recommend using a general houseplant fertilizer at half concentration in the Spring and Summer. As Christmas cacti are adapted to growing on other trees or on rocks in their native habitat, they require a lower concentration of fertilizer compared to other houseplants, so I would urge you always to use half strength. The houseplant fertilizer provides the cactus with all the nutrients it requires to stimulate growth.
- Always water Christmas cacti with a generous soak to ensure that the soil is evenly moist after watering. Watering too lightly only moistens the top few inches of the soil, and the moisture does not reach the roots where it is required, resulting in yellowing stems and a drooping appearance.
- If you have forgotten to water for too long, the soil can dry out and bake hard, which prevents water from infiltrating properly and reaching the roots. I would scratch back the potting soil and feel it to see if it is dry despite watering. In this case, place the cactus in a basin of lukewarm water, ensuring the root ball is submerged for around 10 minutes to allow the soil to absorb moisture properly. This improves the structure of the soil and should prevent the problem of hydrophobic soil. You should be able to water your cacti conventionally the next time you need to water.
Once you find the right balance of watering and address any potting problems, then the Christmas cactus can often revive its original appearance and turn green again.
However, in my experience, it is much easier to revive a yellowing, dying Christmas cactus that is suffering from underwatering or low nutrients than it is from overwatering. If it has been persistently overwatered, then root rot can be the cause of the yellowing stems, which causes the plant to fall apart and die back.
Why is my Christmas Cactus Turning Red or Purple?
- Symptoms. Leaves turning red or purple, often at the edges initially.
- Causes. Too much sunlight.
To understand why our Cacti are turning red, it is important we know how they grow in the wild.
Christmas cacti are native to coastal and mountain regions of Southeast Brazil, where they grow under the canopy of a forest and are typically only exposed to filtered light through the trees at most if not relative, shade.
Therefore, the Christmas cactus’s leaves (which are actually stems) are adapted to bright light but are sensitive to any harsh direct light.
As a defense mechanism, the leaves turn red or purple (depending on the specific cultivar), which is the cactus’s attempt to mitigate any further scorching and damage. (A clever adaptation, don’t you think?)
The Christmas cactus increases the concentration of pigments anthocyanin and carotenoid, which are photoprotective to ensure that the leaves do not scorch to the point they cannot photosynthesize.
I have seen cacti turn purple when cacti are cultivated in fairly deep shade and then suddenly moved to a more sunny aspect without any time to acclimate to the new conditions.
The solution is to simply move the cactus to an area of bright, indirect light that replicates the preferred lighting conditions in its native environment.
Bright light is still important as this promotes flowering.
The best locations for Christmas cacti are bathrooms, as they enjoy the bright light and high humidity, or in a bright room with a sheer curtain, which I find does a great job of diffusing the light, which prevents the cacti from suffering in the sun.g
I have seen the reddish purple colorations reduce once the Christmas cactus has been moved to an area without harsh sunlight in the following weeks.
- A dying Christmas cactus is usually because of overwatering and temperatures colder than 50ºF (10ºC). Christmas cacti need the top 2 inches of soil to dry between bouts of watering and prefer warm tropical temperatures. If the soil is consistently damp and the air is too cold, the cactus’s leaves droop, fall off, and die back.
- Christmas cactus leaves turn red or purple if they are located in too much direct sunlight. Christmas cacti are native to Brazilian rainforests and grow in the shade; therefore, indoors, they should be grown in bright, indirect light to avoid turning red or purple.
- Christmas cacti turn yellow because of overwatering, underwatering, or low nutrients. Mature Christmas cacti can exhaust the potting soil of nutrients, which turns the leaves yellow with a drooping, dying appearance.