Christmas cactus is native to rainforests rather then deserts and requires watering so that the soil is evenly moist. Water 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 Christmas cactus native environment.
Christmas cactus are very unusual for cacti in that are adapted to rainforests rather then deserts which means it prefers 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 cactus in your home, for the optimal balance of moisture so that it thrives…
How Often to Water Christmas Cactus
Christmas Cactus (Schlumbergera) are a type of cactus that grows in cool, mountainous forests in Brazil in shaded areas with high humidity and relatively frequent rainfall.
This type of environment is in stark contrast to most cacti which tend to thrive in dry arid sunny areas.
Therefore one of the most frequent problems with growing Christmas cactus is usually not watering often enough as they are adapted to cool humid conditions unlike there desert dwelling counterparts.
To grow Christmas cactus successfully in your home you have to replicate some of the watering and humidity conditions of its native habitat.
Christmas cactus requires higher humidity then most house plants. Mist the leaves with a spray once or twice per week. Give the cactus a generous soak of water once a week throughout the year.
This frequency of watering combined with the right well draining potting soil helps to mimic the balance of moisture to which it is accustomed avoid problems with bother over watering and under watering.
The soil should feel evenly moist for most of the week drying slightly on the surface before the next bout of watering.
Christmas cactus are also somewhat more drought tolerant then 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.
It should be noted that there are several factors which 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).
- 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 require moist yet well draining soil).
If you are in a climate of low humidity or the air con is often flowing then it is important to mist your Christmas cactus to create a micro-climate of increased humidity to counteract the affects of dry air.
I recommend misting at least once per week regardless of climate as homes tend to be on the dry side but in dry climates mist the cactus 2 or 3 times per week.
Remember that Christmas cactus prefers indirect light rather then 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 Over watered or Under watered…
The cactus can shrivel and droop as a response to over watering and under watering so the only way to distinguish the cause is to feel the soil.
If it is dry both at the surface and at base of the pot (feel the soil at the base through the drainage hole) then the cactus is suffering from under watering.
Increase 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 the dry.
Mist the under watered cactus more regularly to increase the humidity and reduce water loss through the leaves.
If the soil feels damp or even saturated then check that there is nothing blocking the drainage hole and empty any water that may be in a tray or saucer used underneath the pot.
Over watering or damp soil can stop 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 much water you use when watering Christmas cactus should stay the same.
Water Christmas cactus with a generous soak so that excess water trickles out the base of the pot.
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 requires.
A generous soak also encourages the roots to grow and establish in the potting soil.
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 reaching the water all together, 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.
(If your Christmas cactus is dropping buds, read my article for more information)
Well Draining Soil Maintains Optimal Balance of Moisture
Good watering practices should be in conjunction with the right sort of well draining yet moisture retentive potting mix to keep Christmas cactus healthy so that the soil can stay moist but not damp to avoid root rot.
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 a epiphyte like many cactus 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 requirements of the plant without causing root rot.
(Read my article, how to revive a dying Christmas cactus).
Plant Christmas Cactus in Pots with Drainage Holes
Whilst Christmas cactus prefer moist and humid conditions they dislike their roots being sat in water for any length of time.
It is essential that your pot or container has 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 then water pools around the roots causing root rot and the plant dies back.
It should also be noted that Christmas cactus prefers smaller pots and being 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.)
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.
- Saucer and trays underneath the the pots or containers. Christmas cactus requires well draining soil. Saucers and trays are often used to prevent watering spilling in the home. Empty the saucer or tray regularly to ensure water is not pooling around the roots.
- Decorative outer pots. Christmas cactus are often sold in stores 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.
- 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 are native to rainforest and require more watering and humidity then 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 staying damp and promoting root rot.