This article was last updated by on

Christmas Cactus light Requirement: A Complete Guide

Christmas Cactus is a perfect celebratory plant for its vibrant flowers that brighten up your home every holiday season, but only when the light requirement is fulfilled.

You heard it right! The signature pink or lilac-colored blossoms are only possible with appropriate lighting.

Christmas Cactus with bloom
Christmas Cactus with bloom
Christmas Cactus requires 8 hours of indirect sunlight (over 10 hours in the case of artificial lighting) and 16 hours of darkness to produce magnificent blossoms and maintain healthy-looking foliage. Place the plant near East or North-facing windows to meet their light requirement.

Anything more or less will affect food production, leading to discolored leaves, dropping blossoms, and other problems.

However, if the plant leaves are suddenly bleaching or losing their signature green color, you should know that it is under light stress.

Overview of Christmas Cactus

Christmas Cactus is known for its rich, bright flowers and lush green leaves, making it one of the most holiday-gifted plants.

Why the name Christmas Cactus? These epiphytic succulents bloom in November and last until February, coinciding with the holiday season.

Did you know these plants only flower from April to May in their natural habitat and bear no resemblance to Christmas?

However, do not be confused by similar-looking plants sold as Christmas Cacti.

The true Christmas Cactus will have stems arching downwards with a closed habit, and the stem margins will be rounded with tiny visible points (nubs).

Nonetheless, they make beautiful houseplants widely grown and gifted in many United States households.

Here is the overview of Christmas Cactus.

Scientific nameHybrid Schlumbergera ×buckleyi
Common nameChristmas Cactus, Christmas Cacti, holiday cactus, zygocactus
Genus/FamiliaSchlumbergera (Zygocactus)/Cactaceae
NativeSoutheast Coastal Brazil
USDA Zone9-11
For both indoor and outdoor plant
Temperature60-70°F (15-21°C)
Life-spanIndefinite when provided with ideal care
Growth6-12 inches tall and 12-24 inches wide
Grown forGrown for cerise (red) flowers but are also found in different colors such as pink, yellow, or orange
Foliage colorGreen
Blossom TimeNovember to February
Blossom PatternTubular flowers not bigger than a few inches
FruitPollinated flowers produce blueberry-like fruit full of tiny black seeds
Soil acidityAcidic (5.5-6.2 pH)
ToxicityNon-Toxic to humans and pets

The real struggle with the plant begins during its blooming period when the sunlight is at its minimum due to a change in the earth’s tilt.

Fun Fact: The plant is not a true Cactus. In fact, it is not even quite as drought tolerant as the Cacti, so do not treat it as one.

How Much Light Does Christmas Cactus Need?

Christmas Cactus is a pan-tropical plant that thrives in shades of large rocks and trees.

When grown as a houseplant, Christmas Cactus naturally thrives in indirect sunlight for 8 hours a day with 16 hours of complete darkness to set buds for flowering.

A few hours of early morning or late noon sun will do wonders for the plant.

However, ample lighting plays a vital role in developing blossoms; hence avoid keeping the plant in low-light conditions.

In the summer, Christmas Cacti can be moved outside, but they must be kept in a partially to completely shaded area to avoid burns due to harsh sunlight.

As the plant blossoms in fall and winter, you must keep them under LED grow light to ensure they develop signature holiday flowers.

According to the New York Botanical Garden, an emphasis on red (for flowering), blue (for green foliage), yellow, and green wavebands will help boost plant development.

A light-deprived plant may do well only for a few weeks before exhibiting low-light problems and ultimately dying.

So, consider growing them outdoors only if you live in a warm climate, USDA zone 9 or above.

Signs Your Christmas Cactus Is Light Deprived or Saturated

The symptoms of light-deprived Christmas Cactus are less vivid than those of a light-saturated plant because the plant usually thrives in low light.

One of the earliest indications of a faltering Christmas Cactus due to lack of sunlight is the loss of green pigmentation on the leaves.

Do not be surprised when your Christmas Cactus appears bleached, exceeding the light requirements, excess UV exposure, and heat.

The light-saturated Christmas Cactus is too quick to show signs of problems.

Infographics expaining Christmas Cacti's sign of light deprivation on the left and light saturation on the right.
Acting upon the plant’s sign and providing sufficient light is essential.

Note: A sun-exposed Christmas Cactus is likelier to wilt and die than its light-deprived counterpart.

How to Ensure Christmas Cactus Light Requirement?

Christmas Cactus hails from the Brazilian rainforest that provides ample sunlight and shade. Mimicking its natural home ensures healthy plant growth.

1. Plant Location

Introduce them to an ideal location around the house that receives dappled sunlight for at least 8 hours a day.

The east-facing window is best for the plant, where they can enjoy 4-hours of morning sunlight.

Alternatively, keep them in the south-facing window at least three feet away to avoid direct sunlight.

Some Christmas Cactus are conditioned to grow on the patio and garden, where the noon temperature tends to go above 80°F.

However, remember to gradually expose the plant to direct sunlight for a few hours every day before permanently moving them outdoors.

As per the rule, place the plant in low-intensity sunlight two hours a day for over four days before moving them.

Look for a garden location with gentle morning sunlight or dappled afternoon light.

2. Light Intensity         

Christmas Cactus grows best in the dappled light of 65 to 80%, approximately 1500 to 3000 FC.

As a flowering plant, it naturally prefers higher light intensity, usually 2500-3000, during the blossoming period.

Anything over 4000 Foot Candles will burn the plant leaves. Direct sunlight has an intensity of 10,000 FC, making it quite harmful.

Here is a small table describing the light intensity and exposure provided.

Light IntensityFootcandlesLight Exposure
Low-medium 25-400North-facing window
Medium-Bright500East-west facing window
Bright-High Light500-1000South-facing window
Direct Sunlight+10004-6 hours of direct sunlight

Although the plant does well in low light, the flowering will falter due to a lack of proper light intensity and color spectrum.

Ensure the location has ample relative humidity, over 50%, when exposed to high light intensity.

3. Light Duration

The lighting duration will depend on the plant’s stage, germination, flowering period, and stasis.

Generally, Christmas Cactus would require 10-14 hours of lighting to germinate, about 8 hours to produce blossoms, and even less when it reaches stasis (maturity).

Remember to provide anywhere from 6-8 hours of dappled sunlight every day, especially near fall and winter, to boost the growth of blossoms.

When grown under artificial light, provide 10 hours of lighting and 14 hours of darkness.

You can increase the amount of dark, especially when they are amid the blossoming season.

4. Light Quality

The light quality is crucial for Christmas Cactus growth, especially when you live in a colder USDA zone.

You’ll have to compromise on the growth rate of your beloved Cacti due to the lack of sunlight.

When keeping them under growth light, use full-spectrum lighting that combines red and blue colors to induce healthy growth.

The best you can give your Christmas Cactus is light with a color temperature of 6000K to satisfy the light requirement for optimum growth, healthy leaves, and flowering.

A droopy Christmas Cactus in a red plastic pot by the curtained window.
Low Quality light makes the plant droop.

Meanwhile, the smaller green, yellow, and infrared wavelengths will help boost photosynthesis.

We recommend using our light color and spectrum chart to determine the appropriate light quality for your Christmas Cactus.

Does Christmas Cactus Grow in Artificial Light?

The Christmas Cactus quickly adapts to low light conditions but will readily produce blooms when exposed to sunlight.

Ensure to keep them in a location with indirect sunlight during the day and complete darkness at night when blossoming, usually fall and winter.
If not possible, compensate for indirect sunlight with an artificial grow light for 10-14 hours a day, followed by complete darkness.

The commercial UV LED grow lights will be an appropriate choice because they are designed based on each plant’s lighting requirement.

However, the light intensity may become an issue with artificial lighting when you keep your plant too close to the light source.

Find the light setting between 400-700nm kept at least 12-19 inches away from the plant for 10-14 hours daily.

Exposing them to high-intensity light, over 700nm, to compensate for low lighting may also be harmful as it can quickly dehydrate the plant.

Remember, the Christmas Cactus requires long, uninterrupted dark periods to produce healthy blossoms.

LED LightsFeaturesImage
SPIDER FARMER SF-2000 (200 Watts)Hydroponic grow lamp with dimmable quality provides full-spectrum lighting between 660nm to 760nm.
MARS HYDRO TS-1000 Led Grow LightA hydroponic grow light provides 3x3-ft coverage and offers 660-665nm Red IR/3200-4200Knm/5200-6800Knm, close to natural light.
BESTVA Led Grow Light (2000 Watts)Hydroponic grow lamp with 5x4-ft coverage with options for VEG mode for vegging and BLOOM mode for flowering.
MAXSISUN PB4000 (400 Watts)Hydroponic grow lamp with 4x4-ft coverage that provides between 660nm to 730nm color spectrum.

Tips to Maintain Optimal Lighting Condition 

Here are a few proven tips to ensure optimal lighting for your Christmas Cactus.

  • The plant’s growth potential depends on the location it grows. Find out the lighting duration and intensity for your region.
  • Know that your plant is suffering from over or underlighting when it begins exhibiting the earliest signs like yellowing, red, or pink of leaves.
  • Add a sheer curtain or blind on the window to filter high-intensity sunlight; otherwise, move your plant a few feet back.
  • The light and temperature should go hand in hand to ensure healthy green foliage and blossoms.
  • It would be best if you naturally increased sunlight in spring and autumn but cut it down in fall and winter to induce blossoms.


It all comes down to optimal lighting to ensure your Christmas Cactus keeps blossoming every successive year.

The plant stressed from inappropriate lighting will look unhealthy, fail to blossom, and may soon die.

Make sure you rotate your pot for healthy blooming flowers.

Leave a Reply

Your email address will not be published. Required fields are marked *