A Christmas cactus in full bloom is a great gift idea for that special gardener.  They are easy to care for and can be grown indoors throughout the year.  The flowers range in colour from yellow, salmon, pink fuchsia and white or combinations of those colours.

Light

While the Christmas cactus can adapt to low light, more abundant blooms are produced on plants that have been exposed to high light intensity.  Keep your plants in a sunny location indoors.  Plants can be moved outdoors in summer but keep them in a shady or semi-shady location.  Too much direct sunlight can burn the leaves.  When it’s time to bring the plants back inside in the fall, slowly adjust the plants to life indoors by gradually increasing the number of hours they spend indoors each day.  If you want to grow it indoors in a south or west window, you should shade the plant with glass curtains.  No diffusion of light is needed on the north or east.  May growers move the plants to the broken shade of a porch or patio or plunge the pot in a shady spot in the garden during the summer months. Christmas cactus needs shading from the sun between May and September.

Soil

Well-drained soil is a must for Christmas cactus.  Use a commercially packaged potting mix for succulent plants or a mix on your own.  The ideal soil for Christmas cactus is composed of equal parts of garden loam, leaf mold and clean coarse sand (not sand from the seashore).  Add a quart of wood ashes per bushel of mixture.  One-tenth part by bulk of old dry cow manure may be added if garden soil is poor.

Water

The plant is not a true cactus and is not quite a drought tolerant as the name infers.  However, it is a succulent plant and can store a reasonable quantity of water in the leaves.

Water thoroughly when the top half of the soil in the pot feels dry to the touch.  The length of time between watering will vary with the air temperature, amount of light, rate of growth and relative humidity.  During the summer, water so that the soil is continually moist.  When fall arrives, water the plant only well enough to prevent wilting.

During the month of October, give the plant no water.  Cautiously resume watering in November, but do not let stems get flabby from over watering.  If the atmosphere is dry, place pot on a tray of pebbles.  Keep pebbles moist with water in the tray.

After plant completes blooming, let it rest by withholding water for six weeks.  When new growth appears, re-pot and top-dress with fresh soil.  Resume watering to keep soil fairly moist.

Fertilizing

As tender growth appears in the spring, apply a weak solution of liquid houseplant fertilizer at 2-3 weeks.

Temperature

Prefers warm temperatures, although evening temperatures of 50-55 degrees F can be used to initiate flower bud formation (normally responsive to day length).  From October on, keep the plant where it is cool at night (60-65 F).  Deep away from drafts, heat vents, fireplaces or other sources of hot air.

Propagation

Taking short Y-shaped cuttings of the stem tips easily propagates the Christmas cactus.  A well-tended cactus will reach unmanageable size in time.  To root cuttings for new plants, cut back shoots from the tips, cut at the second joint of each tip.  Place cuttings in a moist peat and perlite or peat and sand mixture.  To avoid rotting, water sparingly.  After two or three weeks, water as you would any other cutting.  When cuttings are rooted, put them in a very loose mixture of good potting soil.

Repotting

Plants should be re-potted every two or three years, or whenever pot is filled with roots and the soil appears to be depleted of nutrients.  Christmas cactus usually is re-potted in the spring, but a plant, which is unhealthy because of the root system, can be re-potted any time of year.

Bud-Dropping

Common causes of bud dropping are over watering, exposure to cold drafts, a position too close to a hot radiator or vent and lack of sufficient potash in the soil.  Water plant sparingly and feel a little liquid manure weekly.

How to Get Your Christmas Cactus To Flower

A medium light intensity and a soil high is organic matter are recommended.  Do not allow the plant to dry out, water when the soil surface begins to feel dry.  The plant may be kept drier in fall.  Cool temperatures or long nights are required to induce blooming.  They will bloom when given night temperatures near 55 degrees and day temperatures below 65 degrees.

Flowering is related to day length and night temperatures.  The temperature range for flower bud development is 55 to 60 degrees for a six-week period.  If temperatures remain in this range, they will develop buds regardless of day length.  If temperatures get above that range, the plant will need 13 hours of uninterrupted darkness each night.  Placing them in a completely dark room, or covering them for the recommended time can do this, or longer, each night with a dark piece of cloth – or keep the plants in total darkness like a closet until buds develop.  For holiday blooms this usually means in late September to mid October

During flower bud formation, stop fertilizing and only water enough to keep the leaves from becoming shrivelled.  Once buds to form, then you can keep the plant in normal light and temperatures.  Keep it evenly moist and fertilize every other week with a mild fertilizer solution

A YEAR WITH YOUR CHRISTMAS CACTUS

January: Flowering

February to March: Resting 55 degrees, infrequent watering

April to May: Water thoroughly when potting mix begins to dry out

June to August: Place outdoors in a shady spot

September to October: Plant prepares to flower.  Reduce length daylight hours.  Keep on the dry side and cool (55 o 60 degrees F) until flower buds form.  Then increase water and temperature.

November to December: Flowering. Water normally.  Temperature no less than 55 degrees F.

This information is also available in a PDF.