A wilting Christmas Cactus with dropping leaves is caused by overwatering and cold temperatures. 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 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 :||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 cause yellowing stems.|
To revive a 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 to learn how to implement the solutions and revive your dying Christmas cactus…
Christmas Cactus Wilting and Leaves (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 due to overwatering, slow draining boggy soils. Underwatering, cold temperatures and low humidity are contributing factors.
Wilting stems on a Christmas cactus is an early warning that the cactus either does not have enough water or the soil is too damp due to overwatering and poor drainage.
Usually 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 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, which results in a wilting Christmas cactus.
If the cactus is persistently damp soil for too long, then sections of the stem begin to fall off and they 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 is also associated with temperatures that are unfavorably cold. Temperatures around cooler then 50ºF (10ºC), particularly combined with overwatering tend to causes sections of stem to fall off.
(Cold temperatures and sudden temperature fluctuations can also cause flower buds to fall off).
This is happened to my Christmas cactus in Winter when the Christmas cactus was kept on a window sill with some of the stems in contact with the glass.
The glass at night was significant cooler then the ambient temperature of the room with exacerbated the cold stress and caused some sections of stem to fall off.
Wilting and dropping leaves can also be because of low humidity.
The Christmas cactus is native to humid tropical Brazil. If the humidity is too low then the cactus looses too much water from its stems which causes it to wilt and for pieces to fall off.
How to Revive a 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 to increase the humidity with regular misting.
- Only water your Christmas cactus when the top inch of the soil feels dry to the touch. Use your finger to detect moisture to determine when the soil typically dries out and watering accordingly. This balance of watering ensures that the cactus’s watering requirements are fulfilled whilst allowing the soil to dry sufficiently to avoid wilting and root rot.
- Mist the Cactus’s stems regularly to recreate a humid micro climate that mimics the conditions of its native Brazilian rainforest environment. Misting creates the optimal conditions for your Christmas cactus and prevents it from loosing too much moisture through transpiration. You can also use a special plant humidifier which are available online if you can’t mist your plant everyday.
- When repotting your Christmas cactus use a potting mix of 2 thirds potting soil and one third 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 imitates the typically drainage conditions of the Christmas cactus’s native habitat.
- Keep your Christmas cactus in temperatures of ideally more then 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).
With the right conditions the Christmas cactus should stop drooping return to its original appearance.
If some sections of stem have fallen off, then this is a great opportunity to propagate your Christmas cactus. Christmas cacti are very easy to propagate and grow relatively quickly in the right conditions.
Here is a photo of a an section of Christmas cactus that fell off the original plant and successfully rooted in a potting mix of approximately 60% soil and 40% horticultural sand and it has grown into an impressive plant after just two years of growing in the right conditions even flowering significantly.
A well cared for Christmas cactus can live for more then 100 years.
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 this is usually a sign that the roots are in potting soil that is too damp for it to tolerate.
This 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 affect is often exacerbated.
In which case you should follow the 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 to Revive a Yellowing Christmas Cactus
- If your Christmas cactus has been in the same pot for many years, (and roots are visibly growing out the soil) it may be necessary to repot it to a pot one size up. Only repot The cactus into a pot one size up for it original pot as over potting tends to lead to root rot. Ideally repot your Christmas cactus in the Spring as this is when the plant is most resilient to stress. Use a potting mix of 60% potting soil and 40% grit or perlite.
- Use 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 always 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 the in yellowing stems and drooping appearance.
- If you have forgot to water for too long the soil can dry out, and bake hard which prevents water from infiltrating properly and reaching the roots. Scratch back the potting soil and feel it to see if it is dry despite watering. In which 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 properly absorb moisture. This improves the structure of the soil and should prevent the problem of hydrophobic soil and 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 addressed any potting problems then the Christmas cactus can often revive its original appearance and turn green again.
However it is a lot easier to revive a yellowing, dying Christmas cactus that is suffering from underwatering or low nutrients then 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.
Christmas Cactus Turning Red or Purple
- Symptoms. Leaves turning red or purple, often at the edges initially.
- Causes. Too much sunlight.
Christmas cacti are native to coastal and mountains regions of South East 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.
The Christmas cactus increases the concentration pigments anthocyanin and carotenoid which are photoprotective to ensure that the leaves do not scorch to the point they cannot photosynthesize.
A cactus is more likely to to red or purple if it has been cultivated in fairly deep shade, then suddenly moved to a more sunny aspect, without anytime to acclimate to the new conditions.
The solution is to simply move the cactus to an area of bright, indirect light which replicates the preferred lighting conditions in its native environment.
Bright light is still important as this promotes flowering.
The reddish, purple colorations should 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 then 50ºF (10ºC). Christmas cacti need the top 2 inches of soil to dry between bouts of watering and prefers 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 re 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.