Gardening: Know what those chemical warnings mean

Nancy Szerlag
Special to The Detroit News
It's wise to know what's in the chemicals you use in your garden.especially if you spend a lot of time among the blooms.

Wacko weather continues to take its toll on our gardens. Record-breaking cold and rain changed overnight to hot and humid weather, and many stressed plants known to be pretty much trouble-free are suddenly suffering from disease and insects. The large stand of Huskers Red Penstemons that has thrived in the OPC Stone House Garden for four years with gorgeous three-season foliage is now covered with fungal scars, and the question is “to spray or not to spray.”  

The first thing to do when choosing a chemical to use in the garden is to read the label. I go right to the warning signal that tells the toxicity category of the product. Below is a list of the labels and the toxicity level they indicate.

CAUTION: A yellow caution label indicates the product is slightly toxic if eaten, absorbed through the skin or inhaled. And, misuse could cause slight skin or eye irritation or an allergic reaction. These chemicals are more harmful to pets and children than adults.

WARNING: This orange warning label indicates the product is moderately toxic if eaten, absorbed through the skin or inhaled. Exposure may also cause moderate eye or skin irritation. It may also be corrosive, reactive or flammable.

DANGER: The red danger label means the product is highly toxic by at least one route of exposure. It may be corrosive, cause irreversible damage to skin or eyes. It may also be highly toxic if eaten, absorbed through the skin or inhaled. In this case the yellow triangle with a skull and cross bones and the word poison will also appear on the package.

POISON: The yellow triangle with the word poison and a skull and cross bones on the label indicates the product is highly toxic and can cause serious injury and even death if there is significant exposure. While you rarely find these products in garden centers and big boxes today, they may be stored on a shelf in your garage.

If you have questions about the use of pesticides, a good place to look is the National Pesticide Information Center: (800-858-7378). The website is filled with fact sheets designed to answer questions commonly asked by the general public about pesticides regulated by the U.S. Environmental Protection Agency. The information is intended to be educational in nature and helpful to consumers when making decisions about pesticide use.  They cover a huge variety of subjects, including pollinator protection, natural and biological pesticides as well as minimum risk products and identifying and controlling a pest. It’s well worth your time to peruse it.

Nancy Szerlag is a master gardener and Metro Detroit freelance writer. Her column appears Fridays in Homestyle. Email her at, Ask Nancy.  You can also read her previous columns at