Most consumers are familiar with common household bleach containing sodium hypochlorite, such as Clorox. Another common but more stable form of bleach is called calcium hypochlorite, often referred to as swimming pool chlorine. A third but less familiar form of bleach is potassium hypochlorite. Nevertheless, all three forms of bleach have the same active ingredient, hypochlorous acid.

A potassium form of bleach called FloraFresh is being sold to supermarkets for use in buckets and vases to hold, display, and sell cut flowers.

The producer claims in part that it controls microbes, extends flower life, and eliminates bucket-scrubbing labor. The information presented here summarizes efforts to investigate some of these claims and other factors under actual and simulated supermarket conditions.

The key results obtained in this study can be summarized as follows:  

• When FloraFresh was used under actual supermarket conditions, display solution bacteria were being controlled in only 19 percent of the 21 solutions tested in nine stores, while internal stem bacteria levels of flowers being held in these solutions were seldom if ever controlled.

• Freshly made FloraFresh remained active in killing display solutions bacteria for an average of 1.7 days after which there was no further bacteria control.

• Solution and internal stem bacteria levels averaged about 10 times higher under actual (uncontrolled) vs. simulated (controlled) store conditions.

• At consumer level, roses lasted 48 percent longer in flower food vs. FloraFresh solutions, regardless of previous store level FloraFresh or commercial holding solution treatments.

• When product and labor costs are considered, claimed labor cost savings at store level for not scrubbing buckets when using FloraFresh were essentially offset by increased FloraFresh costs when compared to commercial holding products.

The following recommendations are based on the results obtained in this study and information contained in 219 published research articles reviewed.

• Make sure all stems are re-cut before putting flowers on display and that no leaves are in the solutions.

• Regardless of display solution type, supermarkets should educate consumers on the importance of re-cutting stems and using flower foods for all flowers purchased, except those sold in vases and arrangements.

• Flowers sold in vases and arrangements should already be in flower food solutions.

• To improve FloraFresh use effectiveness, check for free (not total) chlorine in display bucket solutions daily and change the solution when the test is negative.

• Wash all display buckets and vases between uses. In this regard, please consider the following two questions:

o Are you willing to drink out of glasses or cups that are never washed?

o If the answer is no, then why put flowers in unwashed containers?

A more in-depth version of this article is presented under “Supermarket Study” at www.chainoflifenetwork.org.

Dr. George Staby is a postharvest physiologist specializing in floral crops at Perishables Research Organiation in Florence, AZ and Elk Grove, CA. He can be contacted at [email protected]. Dr. Richard Basel is a food safety microbiologist at Lebensmittel Consulting in Fostoria, OH. He can be contacted at [email protected].