Beautiful blooms are what make a Christmas cactus a renowned houseplant. The plant brightens many homes during the winter holidays, and every owner keeps looking forward to the memorable moment.
However, if your Christmas cactus is not blooming, there could be a problem. Common causes include insufficient light, overexposure to direct sunlight, temperature fluctuations, improper watering, nutrient deficiency, and old age.
Why your Christmas cactus is not blooming
With proper care, a Christmas cactus should bloom profusely year after year. If this doesn’t happen, your plant could be stressed as a result of the following:
1. Too much light
The Christmas cactus is a short-day plant that needs a period of darkness to initiate blooming. This plant blooms in temperate climates during late fall and winter when days are short and nights long.
Generally, to get a Christmas cactus to bloom, you must place it in complete darkness for 12 to 14 hours per day for at least six to eight weeks. Exposure to bright light during this period, particularly artificial light at night, can disrupt the process.
How to Fix
Keep the plant in total darkness, where it can get between 12 to 14 hours of darkness and bright indirect light for the day’s remaining hours. Be sure not to interrupt the darkness session because even a little light will reverse the process.
2. Temperature fluctuations
The Christmas cactus is typically sensitive to temperature changes. It requires temperatures of around 70-80°F (21-27°C) during the data and 60-68°F (16-20°C) at night time to initiate blooming.
Temperature fluctuations outside this range may cause the plant not to bloom. Additionally, Christmas cactus buds fall off when temperatures are not stable.
What to do
If you want your holiday cactus to bloom, lower the temperatures to between 55 and 65 degrees Fahrenheit. Also, avoid placing the cactus in overly warm, sunny spots or near heat vents and fireplaces.
Christmas cacti are epiphytic plants that usually get moisture from the atmosphere. When planted in a pot, they require to be watered sparingly. The Overwatered Christmas cactus won’t be in good health to produce flowers.
Excess water in the soil blocks oxygen from reaching the roots causing them to rot. This stops the uptake of water and nutrients necessary for energy production. The plants end up wilting and eventually dying.
The best fix
To avoid the problem of cactus root rot, allow the top inch of the soil to dry out before watering. Water the plant deeply and then allow excess water to drain away. Do not let the pot sit in standing water, as it can contribute to root rot.
Further, make sure the cactus is planted in well-drained soil. The pot should also have good drainage holes at the bottom.
4. Incorrect pot size
Christmas cacti grow better when pot-bound, and using a smaller pot will make it bloom generously. When planted in a bigger pot, the plant focuses on filling the roots instead of flowering.
However, severely root-bound plants may also not flower. Roots that have outgrown the pot will have difficulty taking up nutrients and water. This leads to low production of sugars and energy necessary for a blooming process.
The best solution
Although a Christmas cactus likes to be root-bound, it should be repotted when the roots how outgrown the pot. You will know this when you see roots popping out on top of the soil or through the drainage holes in the pot.
Ideally, repot your Christmas cactus after every 3 or 4 years. Use fresh soil mix and a pot slightly bigger than the current one.
4. Insufficient water
Cutting back on watering typically helps a Christmas cactus get into dormancy, an important period for blooming. However, insufficient watering during active growth may weaken the plant and make it unstable to bear flowers.
What to do
Water your Christmas cactus regularly in spring and summer to prepare for the blooming season. Water thoroughly every when the top inch of the soil feels dry, but don’t let the soil remain soggy.
Cut back on watering as fall starts and provide the conditions necessary for blooming. Increase watering when the flower buds open just to sustain soil moisture.
6. Too Much Fertilizer
It is important to fertilize a Christmas cactus monthly from spring to fall when the plant is actively growing. However, feeding the plant in the fall will prevent flower buds from forming.
Additionally, fertilizing excessively causes the cactus to grow leafy at the expense of flowering.
How to Fix
To avoid over-fertilizing, it’s important to use a balanced fertilizer formulated specifically for cacti or succulents. Fertilize your Christmas cactus every four weeks during spring and summer when the plant is actively growing.
Stop fertilizing the cactus during the fall and winter months when the plant blooming.
In summary, several factors can cause a Christmas cactus not to bloom, including interrupted darkness, temperature fluctuations, and overwatering. Further, incorrect growth conditions can harm the plant’s health and ability to produce buds and flowers.
Make sure to meet the plant’s water, nutrients, light, and temperature needs to increase its chances of producing beautiful flowers during the winter holiday.
- Michigan State University Extension: The secret to getting a Christmas cactus to bloom
- Iowa State University Extension: Is it a Thanksgiving, Christmas or Easter Cactus
My name is Diane M Lewik, and I am the founder of this website. I am a degree holder in plant biology from the University of California – Berkeley. Over years, I have cultivated a vast collection of succulents and I have learned a great deal about how to grow and care for these unique plants.