Bringing together two words that seem to contradict, the Christmas cactus (Schlumbergera x buckleyi) earned its name from the time of year it tends to bloom.
The similarly named Easter cactus and Thanksgiving cactus are one of the three-holiday cacti.
Of course, the three plants look very similar, and often the even, rounded teeth, drooping blooms, and pink pollen are the only proof you have an actual Christmas cactus.
But you might be surprised to hear that this cactus can be grown outdoors, where the blooms can brighten up an otherwise dormant winter garden.
How Do You Care for Christmas Cactus Outdoors?
Growing a cactus outdoors takes the proper hardiness zone and some special care.
However, once these needs are met, caring for Christmas cactus plants outdoors can be easy.
Temperature and Zone
By far, the most important factor in growing a Christmas cactus outdoors is ensuring it doesn’t get too cold for the plant.
USDA hardiness zones 9a, and warm temperatures are best for outdoor planting, although you may bring a potted plant outdoors when the temperature is above 50° degrees Fahrenheit.
You will want to provide some form of shelter for your outdoor plant if the temperature hits 40° degrees Fahrenheit, as it’s easily damaged by frost.
Try to avoid a drafty spot, as Christmas cacti can suffer bud drop in sudden temperature changes.
NOTE: Flower buds start forming when nighttime temperatures are around 55° degrees Fahrenheit. They commonly bloom from November through January.
Look for a garden location with gentle morning sunlight or dappled afternoon light. Direct sunlight can bleach the leaves out.
Indirect light or partial shade in the early afternoon is suitable in areas where the noon temperature is above 80° degrees Fahrenheit.
If you plant the cactus in the dappled shade of a deciduous plant, it will appreciate the full winter sun and summer shade with high humidity.
These plants will also flower more in cooler temperatures, with at least 13 to 16 hours of total darkness during the changing seasons.
Soil and Watering
Cacti are a type of succulents generally adapted for arid environments but share their tropical cousins’ ability to store water.
In the case of a Christmas cactus, this water is stored in the stems, and too much water can cause the stems to swell and discolor.
More importantly, it can quickly develop various forms of rot when exposed to too much water, so it’s essential to ensure the soil is well-draining.
If container-grown, choose pots with adequate drainage holes.
Before planting, you may wish to add gravel to provide a buffer zone in case of heavy rain.
This gives water somewhere to go until it can drain into the water table.
Avoid heavy or clay soils, as these tend to retain too much water.
Instead, loamy, sandy soil is ideal, and you may wish to potting soil in some perlite and orchid or pine bark to improve drainage further.
As this plant loves rich soil, you may wish to add a little compost to the soil each spring to help promote growth.
Water when the soil has become dry to the touch, but try not to let the soil dry out completely.
Avoid watering during the winter to reduce the risk of frost damage and give the plant a bit of down time.
You should also try to give it a little shelter when big storms pass through to prevent flooding.
When repotting, do it in late spring.
For fertilizer application, feed your Christmas Cactus with a balanced liquid fertilizer with a nutrient ratio such as 10-10-10 NPK during the growing season, from April to October.
This is a relatively low-maintenance plant, but you may wish to prune away the stems in spring, removing 2 to 3 segments.
This not only helps shape and size the plant, but it will also allow it to grow back fuller and encourage new growth.
You may choose to add an insulating layer of bark mulch over the roots in the fall.
However, ensure to avoid warm air from heat vents or cool drafts, as it can result in flower bud drops.
Pests and Diseases
Indoor plants tend to be far more sheltered from common pests and diseases, so it can be easy to forget these risks when planting outdoors.
Root rot is the primary disease, but fusarium, phytophthora, and pythium are three fungal infections the plant is susceptible to.
Fungus gnats tend to be the most common pest indoors, but aphids, spider mites, and mealybugs may be a bigger problem outdoors.
These problems are easily avoided by proper watering and a neem oil soak or insecticidal soap every 2 to 3 weeks.
You can also use a cotton swab dipped in rubbing alcohol to wipe these insects.
Growing these houseplants outdoors can be very rewarding, but you have less control over the outside plant’s environment, so it’s best to plan when preparing to plant a Christmas cactus out in the garden.
They make great additions to desert-themed and rock gardens but may be best kept in a hanging basket if you’re in an area where the weather tends to be rainy or prone to quick, significant changes in temperature.