Christmas Cactus Preparation

From the archives of Dan Culbert, former UF/IFAS Extension Okeechobee County horticulture agent. This article originally appeared in the October 2011 Neighborhood Gardener newsletter from the Florida Master Gardener Volunteer program..

Christmas cactus with red flowers on a glass patio table

Schlumbergera hybrid Christmas cactus. Photo: Scott Zona, some rights reserved.

The holidays are coming upon us and it's time to start getting your Christmas cactus ready to bloom. Many people have these plants for years, but it can be tricky getting them to bloom when you want.

To ensure blooming

Christmas cactus, like poinsettias and chrysanthemums, is a short-day plant. They produce leaves when the days are long in the summer, and form flower buds in response to shorter days in the fall. Cooler temperatures also help stimulate flower production.

Christmas cactus grown in natural light will flower when the days become shorter. If these plants are exposed to any artificial light, like a streetlight, they will not set flower buds as expected.

To make Christmas cactus bloom during the holidays, they need to be moved to a dark area (like a closet) from 5 p.m. to 8 a.m. each day. This short-day treatment should last for six weeks. Plants kept like this will bloom in about ten weeks. For example, placing your plants in the closet around October 14th should have them in full bloom around December 23rd.

Christmas cactus care checklist

Light – Plants grow best in bright light and should be placed within 6 feet of a window. Any light exposure will work with the exception of north windows. When new growth begins following bloom, prune plants to force branching. The last pruning should be done in late spring. This will increase the number of flowers. The leaf segments can be pruned off with shears, or just pinched off with your fingers.

Soil – Make sure the soil is well-drained and light. If the soil holds too much water, the plant stems or roots will rot. Combinations of peat moss and perlite, vermiculite, or builder's sand are all acceptable soil choices. Try a mix of two parts peat moss to one part perlite for a rich but well-drained media.

Water – Watering is one of the keys to success with these plants. Allowing the soil to dry out will cause the flowers to drop. On the other hand, soil that is too wet will lead to disease problems. It's important to keep the soil moist but not wet. A light, airy soil media that's rich in organic matter is the most forgiving. A Christmas cactus needs freely draining soil and a pot with open drainage holes. Water whenever the top inch of soil feels dry rather than on a fixed schedule. Water thoroughly, until water runs out the bottom. If the soil becomes too dry and won't absorb water, water every 10 minutes until it holds moisture. Afterward, pour out any water that accumulates in the saucer.

Fertilizer – Fertilize every month or every two months, depending on the growth of the plant. If it's growing rapidly, monthly fertilizer applications would be best. Soluble fertilizers or slow-release products are both acceptable. You may want to reduce the rate that is listed on the label, because excess fertilizer salts can damage the roots.

Heading off problems

A common problem with holiday cactus is bud drop. This usually occurs because of a change in environment, especially high temperatures. To avoid bud drop, do not place the plant in a draft or near a heat source (vent, fireplace, or television). Another cause of bud drop is improper watering.

For more information, contact your local Extension office.

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