How to Care for Christmas Cactus

The Christmas cactus (Schlumbergera x buckleyi) joins Norfolk Island pine trees and poinsettias as plants beloved during the winter season. While it may seem like an unusual holiday plant, the Christmas cactus, also called holiday cactus, is flush with bold blooms, making it a welcome sight in the middle of winter. The fleshy segmented stems of the plant are flattened leaves and slightly serrated on each side. In late fall or early winter, tubular flowers bloom on the ends of each stem.

Originating in the Brazilian rainforest, Christmas cacti grow in their native environments on moss-covered trees (as epiphytes) or in rock crevices filled with decaying vegetation (as lithophytes). They are found in cool but humid, shaded environments and do not root in soil.

Despite this, Christmas cactus grows well in pots outdoors in the shade or indoors next to a window with bright, indirect light. All varieties of Christmas cactus can be started any time of the year indoors as a houseplant until the summer when you can replant or move it outdoors. Given the right care, your cactus should grow fast achieving a spread of two feet in just a few years with blooms at the beginning of each winter.

The best conditions for growing a Christmas cactus are regular potting soil, diffused light, soil that dries out completely between waterings, and temperatures between 70°F and 80°F during the growing season until about September. Once buds set, the cactus needs 55°F to 65°F and 13 hours of darkness every night for the blooms to open.

Christmas Cactus Care

Taking care of a Christmas cactus is a little trickier than most other desert-loving cacti that are drought resistant.

• Plant in average soil and give 4 to 6 hours of diffused light daily.
• Provide temperatures between 70°F and 80°F. throughout the growing season.
• Feed with half strength water soluble balanced fertilizer in spring and again in early summer
• In September/October Move Christmas cactus indoors to a diffused light location.
• Withhold fertilizer and allow soil to dry almost completely between waterings.
• Induce flowering by providing at least 12 hours of darkness every night.

To encourage more stems, grow your Christmas cactus as a hanging plant or place it where it has room to drape. You won't need to worry about touching thorny spikes as you do with other types of cacti.

Planting Christmas Cactus

The best pots for cactus plants are terracotta or clay pots. These pots are porous and wick away water from plants that can be harmed by overwatering. The pot should have many drainage holes or one large one at the bottom.

When repotting, choose a container that is only 1 to 2 inches bigger in diameter than the current one. A pot larger than that can retain too much moisture or invite insects and plant diseases. 

Light

Provide Christmas cacti with 4 to 6 hours of diffused light during winter bloom months. The plant likes sun and shade, but you have to take care not to give it too much of either one. Holiday cacti prefer partial shade or diffused light, although they are adaptable to other conditions. If you expose them to full sunlight, ensure it's during the winter months; too much sunlight in the spring and summer can cause the plant to become pale and yellow.

Soil

Plant your Christmas cactus in a loamy, sandy, perlite mix, cactus mix, or general-purpose potting soil. Soil is not an essential factor; it's adaptable to most soil conditions and grows naturally as an epiphyte in its native region. To achieve optimal growth, it prefers a pH level between 5.5 and 6.2; peat moss is a helpful additive for a more acidic environment.

Water

Water Christmas cacti thoroughly once the soil has completely dried out since its last watering. You will know if the soil is too dry when the leaves start to pucker and shrivel. Allow excess water to run out through the drainage holes.

During a hot, sunny summer, water the plant two to three times a week. If the plant is located in a sunny window during the winter, it might need water once a week. To check the moisture level, place your finger 2 inches into the soil; if it's dry to the touch, water thoroughly. If you keep the plant in a cooler location away from a window during the winter season, it might only need water once every two to three weeks.

Temperature and Humidity

During its peak growth months (April to September), Christmas cactus prefers balmy temperatures between 70°F and 80°F. Once the buds are set, it requires low nighttime temperatures (between 55°F and 65°F) and at least 13 hours of darkness to flower. Keep it away from heating vents, frequently-opened doors, and drafty windows; this plant does not like to be exposed to sudden drafts or temperature changes and it will drop its buds or flowers if it's unhappy.

The Christmas cactus needs ample humidity, especially when grown in the dry conditions of heated homes during the winter. Either mist the plant or place a pebble tray filled with water beneath the pot to boost its humidity levels.

Fertilizer

Feed your Christmas cactus monthly with a half-strength, diluted water-soluble balanced fertilizer during the early spring and summer months. Once you've noticed the formation of flower buds—usually late summer or early fall—stop feeding. After the plant blooms, you can resume monthly feedings.

Types of Christmas Cactus

Schlumbergera x buckleyi is a hybrid plant often called by other names such as Thanksgiving, Christmas, or Easter cactus. They look alike but bloom at different times and have slight differences in the shape of their leaves. Because of their subtle differences, they are often mislabeled in garden centers.

• Thanksgiving cactus (Schlumbergera truncata): This plant blooms close to the end of November with showy flower colors that are either red, pink, peach, purple, orange, or white. It has very pointed and claw-shaped projections on the edges of its leaves.
• Christmas cactus (Schlumbergera russelliana): Often bred with S. truncata to form Schlumbergera x buckleyi, this species blooms close to the end of December with magenta and white flowers. It has flattened leaf segments that are rounded with a few notches around the edges.
• Easter cactus (Rhipsalidopsis gaetneri): This variety starts to reveal star-shaped flower buds in February and flowers from March through May. It has tiny bristles on the edges of its rounded leaf segments.

Pruning

Prune a Christmas cactus right after it blooms, when it enters a new growth period extending its growth segments. Pruning will force the plant to branch out, and it will grow more of its distinctive stems. You can also prune safely from after bloom to late spring without harming the plant.

To prune a Christmas cactus, give the stems a twist between one of the segments. You can also use a sharp, sterilized knife or scissors to remove segments. You can remove up to a third of the plant per year or, more conservatively, trim off one to two segments from the end of each stem.

Propagating Christmas Cactus

The best time to propagate a Christmas cactus is one to two months after it's finished blooming. Avoid propagating it in the fall while it sets its buds and as it's actively flowering. Taking cuttings of Christmas cactus, large or small, will help the original plant grow fuller and bushier, resulting in more blooms in the future. Christmas cactus is best propagated from stem cuttings.

To begin, prepare a 4- or 6-inch pot and fill it with a growing medium like a cactus mix, all-purpose potting soil, or a sandy/peat mix. Optionally, you can root your segment in a clear jar of filtered water before planting it.

1. Use your clean hands or a sterile knife or scissors to cut sections of stems with three to five stem segments on each.
2. Place the stem segment in a cool, dry place for two to four days until the cut end callouses (dries out) to protect the end from rotting.
   
3. Push the cuttings about an inch deep in the lightly moistened soil. Three stems fit nicely into a 4-inch pot; five stems in a 6-inch pot. It should take two to three weeks for roots to form.
4. Water the plant well. To create a humid environment and encourage rooting, cover the plants and container with a clear plastic bag secured with a rubber band. Remove the plastic bag once rooting has started.
5. Care for it as usual. Wait at least eight to ten weeks before repotting to a permanent home. The best evidence of good rooting is new leaf or stem growth.

Optionally, you can root the stems in water before planting them in the soil. Set the cut end in 1 to 2 inches of filtered water, then place the jar in a window with indirect light. After several weeks, the stems should have roots at least 1 or 2 inches long and are ready to plant in potting soil.

How to Grow Christmas Cactus From Seed

You can harvest cactus seeds from the pods (fruits) of the plant. If the pods are still green, wait until they turn red. The pod transformation usually happens in the fall. Extract the brownish-black seeds and wash the pulp away.

1. Plant the seeds in moist sphagnum peat moss and vermiculite, loamy compost, or cactus mix. Press the seed into the soil without covering it or sprinkle a thin layer of vermiculite on top.
2. Cover the pot with clear plastic wrap or enclose it in a clear plastic bag to increase humidity in the growing environment.
3. Place the plant on a bright, but indirectly lit, window sill.
4. Keep growing medium moist. Mist the soil surface with water every day, or water the plant from the bottom by placing the pot in a tray of water.
5. Within two to three weeks, seedlings should emerge. Remove the plastic once you notice seedling growth.
6. Transplant the seedlings into individual pots when they are large enough to handle.
   

Repotting Christmas Cactus

Christmas cactus likes to be rootbound and does not have to be repotted often—every three to four years is sufficient, or when the plant starts looking ragged or you see a lot of roots growing out of the drainage holes. Frequent repotting can damage the plant and can cause it to stop blooming for a while.

Unlike other plants that are best repotted when they display new growth in spring, for Christmas cactus, wait until blooming ends and the flowers have wilted in late winter or early spring. Never repot the plant while it is actively blooming.

Overwintering

Holiday cacti are not cold hardy and do not tolerate frost. These tropical plants can remain outside in USDA hardiness zones 10 to 12 (certain parts of California, Florida, Hawaii, and Puerto Rico). They can handle nighttime lows in the 60s, but anything approaching freezing can kill the plant. Bring the plant indoors before the first frost and maintain drier soil. The colder temperatures should spur bud production. You should begin to see buds forming by October.

Common Pests & Plant Diseases

The most common pests that infect holiday cacti are fungus gnats, flower thrips, aphids, spider mites, and mealybugs. Do not overwater your plant; soggy soil is what most often attracts these pests. Insecticidal soap and horticultural oil are usually effective in controlling an outbreak. The tiny pests can also be removed by blotting them with an alcohol-soaked cotton ball. 

Fungal diseases are common when plants are overwatered. Avoid overwatering to prevent fungal infections. Fusarium and Phytophthora are two common Christmas cactus fungi that can cause stem rot.

Fusarium stem rot causes brown spots to form on the stem at the soil line. A Christmas cactus might rebound from the fusarium if caught early enough, but it's often hard to save. If the plant has overly wet soil, allow it to dry out, then apply a fungicide according to the package instructions.

Phytophthora stem rot causes the stem to appear wet or water-soaked at the soil line. Phytophthora is deadly.

How to Get Christmas Cactus to Bloom

Under the best conditions, plants bloom about 18 months after sowing from seed. Each flower will remain open for at least six days, and the plant should continue to bloom for four to six weeks. The Christmas cactus colors are showy but the flowers are scentless. The best way to ensure that your Christmas cactus remains in bloom throughout the winter is by removing the faded flowers or deadheading.

For your Christmas cactus to bloom during the holiday season, you might need to force it into dormancy, then coax it out. Here's how:

1. In mid-October, reduce watering (probably once every week or two). Only water when the soil feels dry about an inch below the surface. Stop fertilizing.
2. Keep your Christmas cactus cool between 50°F to 55°F and make sure to limit the amount of light it gets for about six to eight weeks.
3. During the day, the plant can receive indirect light, but it needs 12 to 14 hours of total darkness at night. If the room is warmer than 55°F, give your plant an extra couple of hours of darkness each day. If light can reach the plant anytime during its 12 hours of "night," cover the plant with a dark cloth.
4. Once flower buds form, move the plant to a bright, draft-free window. Flowers should start opening within a couple of weeks.

Common Problems With a Christmas Cactus

Holiday cacti are long-lived plants that are sensitive to temperature and humidity. They are hardy when kept above freezing temperatures; however, they will require ideal temperatures and conditions for lush flowering during the holidays.

Stunted Appearance or Growth Distortion

If you notice that your Christmas cactus has stunted or distorted growth, inspect it closely for a mealybug infestation. Mealybugs look like tiny white cotton dots about 1/8 to 1/4 inches long. They move slowly and often appear first low on the leaf surface in the dark, warm, moist areas near the center stem of the cactus. The insects feed on plant sap and leave a sticky honeydew substance behind, which causes mold to form on the plant.

Yellowed, Spotted, or Wilting Leaves or Stems

If your plant has yellowing leaves or stems, leaf spotting, or plant wilting, inspect them closely for thrips. Thrips are an insect that looks like thin black slivers or tiny lobster-like insects. The leaf and stem damage is not caused directly by thrips but by a virus they commonly transmit, impatiens necrotic spot virus. Treat the thrip infestation with insecticidal soap or horticultural oil.

Wilting can also be caused by too little light, insufficient water, or if the plant is rootbound. Correct those conditions and monitor closely for improvements.

Leaves Turning Red or Pink

If the leaves of your Christmas cactus turn red or pink, it might either be receiving too much sun or too little water. If your plant is located in a window with direct sun, move it back to indirect light. If the soil is dried up to 1 inch deep, water it more frequently. The rule of thumb is to water a Christmas cactus when the top of the soil feels dry.

Root Rot

Wilting, brown leaves, black or reddish spots on leaves and stems and soggy soil all are indicators the plant may have root rot. If you suspect this problem, remove it from its pot and shake off excess soil. Cut away soggy, discolored roots, replant in a fresh pot with dry potting medium and allow the roots to recover several days before watering.