How often should I water a Christmas cactus?

A Question of the Week
Christmas Cactus

Holiday cacti are incredibly popular gifts throughout the winter and spring and can be purchased just about any place that sells plants, from the grocery store to the flower shop. With their succulent leaves and bright flowers in many colors, holiday cacti are eye-catching and find their way into the homes of experienced and novice houseplant enthusiasts alike. When properly cared for, they can live for decades, often being handed down from one generation to the next.

Three distinct types are typically available at retail stores depending on the season: Christmas cactus (Schlumbergera x buckleyi), Thanksgiving cactus (Schlumbergera truncata) and Easter cactus (Rhipsalidopsis gaertneri), though the name “Christmas cactus” is often used to describe all of them. For simplicity’s sake, it is easier to refer to all three as holiday cacti, as they require very similar care.

Despite “cactus” being in their name, holiday cacti need significantly different care than their desert-dwelling relatives. Holiday cacti are native to the tropical rainforests of Brazil where they grow as epiphytes in the shady branches of trees. Epiphytes are plants that grow on other plants instead of in the soil, and they get moisture and nutrients from the air and rain.

Check the Soil of Your Holiday Cactus

Because of this, holiday cacti do not tolerate extreme drought like other cacti. They should be watered once the potting soil is dry to the touch, allowing excess water to drain freely from the bottom of the container. Do not let the soil become waterlogged by letting plants sit in standing water. Prolonged exposure to overly wet soil, especially in the winter months, can lead to root rot.

How often holiday cacti need to be watered depends on a number of factors such as what the potting soil is made of, how big the container is, how much sunlight the plant receives and how warm the ambient temperature is. The key to keeping a healthy plant is making sure it is placed in the right location and only watering when the soil mix is dry.

Holiday cacti grow best when they are placed in a location with partial shade, such as an east or west facing window, with a temperature between 70° and 80℉. Exposure to too much bright sunlight, especially in the summer months, can burn the foliage and not enough light can slow growth and cause the soil mix to dry too slowly. When in doubt, err on the side of under-watering as opposed to over-watering.


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