Bulbs Forcing Houseplants

Drunken Amaryllis Are Shorter

Amaryllis bulb in a transparent vase with a bottle of rubbing alcohol bottle next to it.

By Larry Hodgson

Question: Every year I buy an amaryllis bulb for Christmas and put it in a vase of water to make it bloom. I follow a tip from style guru Martha Stewart who recommends putting a little rubbing alcohol in the water to shorten the bulb’s flower stem so it won’t fall over. But when should it be applied?

Michel Lapointe

Answer: Actually, Martha Stewart didn’t originate this tip, but just shared one she found elsewhere. 

The actual technique was developed by Cornell University’s Flower Bulb Research Center, apparently following an incident that occurred at their 2002 Christmas party. A drunken student is said to have poured vodka into a vase containing Paperwhite narcissus bulbs that were being forced in water and they grew only about half as high as normal, yet produced perfectly healthy, full-size flowers. Scientists being scientists, they tested this further with other bulbs and various alcohols and found you could indeed reduce stem length of bulbs being grown in water by careful use of alcohol. 

Why this occurs is uncertain, but one theory is that, since alcohol is poisonous to plants (as it is to humans and other animals), applying a small amount of alcohol, enough to slightly poison the plant without killing it, may reduce its growth.

Amaryllis bulb in a transparent vase.
Apply alcohol when fresh roots begin to show. Photo: fluwell.com

Apply the alcohol as soon as new roots begin to form under the amaryllis (Hippeastrum) bulb, emptying the vase of its water and adding the alcohol/water blend instead. The recommended dose is 1 part 70% isopropyl alcohol (rubbing alcohol) to 13 parts water. If you prefer to use vodka, whiskey or another distilled alcohol, the dose would be 1 part alcohol to 7 parts water. Avoid beer, wine, and other sugary drinks. 

You can also use this same technique for any bulb you force in water, such as hyacinths and Paperwhite narcissus.

Do note, though, that bulbs forced in water or in stones set in water (with or without alcohol) are hard to recuperate. Normally, you would simply toss them into the compost after they finish flowering. If you want to save the bulb for future blooms, grow it instead in a pot using potting soil. 

Larry Hodgson is one of Canada’s best-known garden communicators. He has notably been editor-in-chief of HousePlant Magazine, Fleurs, Plantes et Jardins, À Fleur de Pot and Houseplant Forum magazines and is currently the garden correspondent for Le Soleil and radio garden commentator for CKIA-FM Radio. He has written for many garden publications in both the United States and Canada, including Canadian Gardening, Harrowsmith, Horticulture, Fine Gardening and Organic Gardening. He also speaks frequently to horticultural groups throughout Canada and the U.S. His book credits include The Garden Lover’s Guide to Canada, Complete Guide to Houseplants, Making the Most of Shade, Perennials for Every Purpose, Annuals for Every Purpose, and Houseplants for Dummies, as well as nearly 60 other titles in English and French. He is a past president of the Garden Writers Association (now Garden Communicators International) and the winner of the prestigious 2006 Garden Media Promoter Award offered by the Perennial Plant Association. He resides in Quebec City, Quebec, Canada.

2 comments on “Drunken Amaryllis Are Shorter

  1. Instead of poisoning the bulb why not just choose a shorter cultivar or use some decorative support twigs to hold the stem up. Amaryllis can live a very long time so it seems sacrilegious to treat them as annuals

  2. This is weird. I just read about it for the first time about two days ago. I will probably never use the technique though, since I prefer to plant the bulbs out afterward, even though I know that few recover from forcing, even without alcohol.

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