The Use of Listerine on Orchids

Effective Ingredients

• Listerine contains essential oils--strongly-scented compounds found in plants--that act as germicides. The combination of eucalyptol, menthol, methyl salicylate, thymol and alchohol also kills certain orchid pests and acts as a disinfectant. Thymol, a component found in thyme oil, kills mold, repels insects and reduces harmful fungi that live in soil. According to a 2004 article in the “Southwest Farm Press,” University of Florida studies show that thymol and other essential plant oils can be used to rid potted plants of bacteria that cause rot or wilt, kill fungi and fumigate soil.

Pests

• Listerine acts as a preventative measure against infestation by repelling insects and can also be used to kill existing pests. As a preventative, spray your orchids with full-strength Listerine once per week. To reduce infestations, combine a teaspoon each of Listerine and dish soap with four cups of water. Spray the mixture on your orchids every other week. Discontinue if you notice any leaf burn.

Bacteria and Fungus

• Some species of orchids are susceptible to foliar problems caused by fungi or bacteria. If you notice expanding brown patches on your orchid’s leaves, treat them with Listerine. Cut the affected area away using a pair of scissors or shears sterilized with a dip in Listerine. Then spray the area around the damaged portion with an application of full-strength Listerine. Potted orchids are also susceptible to bacterial soft rot and crown rot, caused by bacteria or fungus. To treat rot, use full-strength Listerine and pour it on the affected area. Let the Listerine soak in for five minutes, then gently tilt the orchid’s container and pour away any leftover fluid.

Preservation

• Use Listerine to preserve cut orchids. Commercially prepared cut-flower preservers generally contain dextrose, a carbohydrate energy source that provides flowers with nutrients to stimulate or prolong budding; a biocide to reduce baterial growth; and acid to lower water pH levels, which helps flowers absorb moisture. Listerine fulfills these functions, removing the need to purchase special formulas. Add one ounce of Listerine to each gallon of water.