To Spray or Not To Spray in the Garden - U of I Extension

News Release

To Spray or Not To Spray in the Garden

FOR IMMEDIATE RELEASE

June 20, 2018

Stop and think before grabbing a bottle of pesticide to control garden pests. That’s the message University of Illinois Extension educator Martha Smith wants to convey to gardeners this season.

“Integrated Pest Management stresses monitoring your landscape, keeping a keen eye out for problems from the start,” Smith says. “Ask yourself, should I spray or is there an alternative? Most pest problems start out small.

“Perhaps an infested branch can be removed. Simply hand-picking the critters off a plant can save you time, energy, money, and chemicals. How much pest damage are you willing to tolerate? If you seldom stroll through your landscape you might not see that pest until it has consumed a major portion of your investment. At this time, a pesticide control may be the only choice.”

We are in the midst of gardening season. Pests are sure to attack. Monitoring and considering control options are signs of a responsible gardener, according to Smith. “Remember, a pesticide is any product used to control a pest, and a pest is anything harming your plant. Fungi, insects, bacteria, or rabbits could all be considered pests,” she says.

Both synthetic and organic products are available for controlling garden pests. Regardless of what type of control you select, Smith offers a few tips to effectively apply the product.

  1. Read the label. Understand what the product is intended to do and when during the lifespan of the pest it should be applied. Correct timing will give the best control with the least amount of chemical.
  2. Correctly identify the pest. Caterpillars resemble sawfly larvae but the products to control them can be different. Also, is that caterpillar a true pest? If you choose a caterpillar control, don’t question the absence of butterflies later in the season. Caterpillars can be voracious eaters, but the majority will turn into colorful butterflies. Consider the “pest factor” before spraying.
  3. Mix material as directed. Don’t think if one teaspoon is recommended, two teaspoons will be better. Effectiveness will not increase by doubling the amount of chemical. In fact, higher concentrations can harm plants.
  4. Follow all personal safety instructions on the label. A sleeveless tank top and flip-flop sandals are probably not the recommended protective clothing. Consider a long-sleeved shirt, pants, eye protection, socks, closed-toe shoes, and gloves if not already instructed on the label.
  5. Use measuring utensils – don’t guess at amounts. Have a set of measuring utensils specifically designated for chemicals. Write on them “chemicals only.” Don’t use utensils that are also used in food preparation.
  6. Spray on the target. Don’t apply a chemical across a 20-foot border when only 2-3 square feet require attention - it may not be necessary. Read the label to find out if the entire plant needs to be sprayed. Spray to the point of runoff and stop.
  7. Pollinators can be harmed with certain pesticides. Consider spraying after the plant has finished blooming and pollinators no longer visit. If you must spray while the plant is in bloom, spray when insects are not active, such as dawn and dusk.
  8. Application equipment should be in good working order. Leaks can lead to damage on non-target plants. Use equipment that is recommended on the label.
  9. Spray when the weather is calm. Pesticide drift occurs when spray is carried off-target by the wind. Drift can also be minimized by spraying at a lower pressure and using the largest nozzle opening that will still allow you to complete the task.
  10. Watch the weather and avoid the heat of the day. Some pesticides will burn plant material if applied when temperatures are too hot. High temperatures can also cause some pesticides to evaporate and decompose quickly. Spray in the morning.
  11. Watch the weather and avoid spraying before rain or before overhead irrigation. This will reduce effectiveness by washing the material off the target plant, possibly leading to groundwater contamination.

Keep these spray guidelines in mind when selecting a pest control for your landscape. Monitor and identify the pest early. Consider your control options. Remember your control selection may not be what your neighbor would choose. Be a responsible gardener and ask: “To spray or not to spray?”

Source: Martha A. Smith, Extension Educator, Horticulture, smithma@illinois.edu

Pull date: August 1, 2018