Growing Cacti and Other Succulents: A Toronto Master Gardeners Guide

Kalanchoe blossfeldiana is a colourful flowering succulent that can be bought in supermarkets as well as nurseries. Photo: Helen Battersby

With a sunny window, growing succulents is easy and rewarding. Cacti are one of the best know groups of succulents, but there are many succulents that are not cacti.

Cultural Requirements

To stimulate flowering, keep plants potbound. Flowers usually occur on new growth.

Light Requirements

The majority of cacti need at least 4 hours of direct sun per day. A south window is good. Fluorescent lights may be used. The plants should be set 6 – 12 inches from the tubes and the lights should be left on for 12 -14 hours per day.

Temperature

Cacti and succulents are able to withstand reasonably high daytime temperatures with cooler nights (60 -65 degrees F.) from spring through to fall. During the winter night temperatures should be 45 – 55 degrees F. with higher daytime temperatures. Cool nights are essential to initiate bloom.

Moisture Requirements

Water weekly with tepid water from spring to fall. Hold back on watering as daylight hours get shorter and only water enough to keep the plants from shriveling in the winter. An exception is Crassulas which require reverse watering to encourage flowering.

Choosing the Right Soil

Use a soilless mix containing equal parts of a non-peat moss based potting soil and construction sand. Exceptions are Rhipsallis and Hatiora cactus that require a peat based potting soil, regular watering and indirect light. Bone meal maybe added to the bottom of the pot to encourage root development.

Fertilizer Requirements

Use a half strength water-soluble fertilizer with a ratio of 1:2:1 applied once a month from spring to fall. Withhold fertilizing in winter. Over fertilizing can cause soft new growth.

Pests and Diseases

Succulents are not prone to pests. Dab mealy bugs with rubbing alcohol or methyl hydrate. Pick off scale. Forcefully spray spider mites with tap water. Rot or soft growth is due to over watering or over wet conditions.

References

Succulents II, M. Sajeva and Mariangela Costanza

The Ultimate Book of Cacti and Succulents, Miles Anderson

Date revised: last revised before April 2005.

For printable version, click  Growing Cacti and Other Succulents- A Toronto Master Gardeners Guide

Produced by the Toronto Master Gardeners, these Gardening Guides provide introductory information on a variety of gardening topics.

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