Mother-in-Law's Tongue

Houseplants Image Gallery Mother-in-law's tongue is a toxic house plant with green and white or yellow marbled leaves on thick green stems. See more pictures of houseplants.
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Mother­-in-­law's tongue is sometimes also called dumb cane -- both unflattering names that allude to this house plant's tongue numbing sap.

The dumb cane is so named because its toxic sap, if ingested, can cause a painful loss of speech. It forms a thick, green, canelike stem topped off by a cluster of large, fleshy, oval to lance-shaped leaves lightly to heavily marbled in white or yellow. The greenish flowers are of little interest.


When the dumb cane becomes too tall, air layer the top of the plant, then cut the stem into three-inch sections, and lay them sideways in a potting mix. They will soon produce new plants.

Mother-in-Law's Tongue Quick Facts

Scientific Name: Dieffenbachia sp.

Common Names: Dumb Cane, Mother-in-Law's Tongue

Light Requirement for Mother-in-Law's Tongue: Bright Light to Light Shade

Water Requirement for Mother-in-Law's Tongue: Drench, Let Dry

Humidity for Mother-in-Law's Tongue: Average Home

Temperature for Mother-in-Law's Tongue: House

Fertilizer for Mother-in-Law's Tongue: Balanced

Potting Mix for Mother-in-Law's Tongue: All-Purpose

Propagation of Mother-in-Law's Tongue: Air Layering, Stem Cuttings

Decorative Use for Mother-in-Law's Tongue: Floor, Table

Care Rating for Mother-in-Law's Tongue: Very Easy


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Larry Hodgson is a full time garden writer out of Quebec City in the heart of French Canada where he grows well over 3,000 species and varieties. His book credits include Making the Most of Shade, The Garden Lovers Guide to Canada, Perennials for Every Purpose, Annuals for Every Purpose, Houseplants for Dummies, and Ortho's Complete Guide to Houseplants, as well as other titles in English and French. He's the winner of the Perennial Plant Association's 2006 Garden Media Award.