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Beacon Senior News

Garden pests bugging you?

Jun 27, 2022 03:10PM ● By Bryan Reed

Insects are valuable to our landscapes and ecosystem. Without pollinating bees and butterflies, we get no veggies or fruit. Earwigs and pill bugs are amazing decomposers that eat plant debris and turn organic matter into plant nutrients. Worms and beetles burrow into compacted soils to provide aeration and pathways for irrigation. Springtails and centipedes feed on other small insects and microbes to keep their populations in check, and when they die, their bodies are a powerhouse of trace minerals for plants. 

However, bugs can be difficult to manage. Your first instinct might be to destroy them, but that will wreak havoc on your garden and cause more problems in the long run. For effective ways to manage pesty insects, follow these steps:

Step 1
Identify EVERY insect 

You don’t want to harm beneficial insects, so it’s important to identify the bugs in your garden before taking action. 

For accurate identification, use a hand lens. You may even have to scout in the middle of the night when caterpillars or cut worms are active. Insect books are handy, but I really like www.insectimages.org for identifying insects in each phase of their life cycle. 

Keep in mind that insects appear differently at various stages of their lives. For example, juvenile ladybugs look nothing like adults, with their slender black profiles and orange stripes. 

Once you know what squash bug eggs look like, flicking them off of leaves is much easier than managing voracious adults. 

Calling the CSU Extension Master Gardeners and describing the damage an insect is causing can aid in identifying the culprit. Is it a small-mouth insect that’s making shot holes within the leaf or a large-mouth insect that’s eating the edges? Are there ruffled leaves from a sucking insect or any discoloration around the puncture wound on the leaf? 

Step 2 
Prevention tactics

To keep problematic insects under control, prevention is a time-worthy approach. 

Squash bugs and aphids can lay eggs in the soil. Rotating crops causes these pests to have to find their food source after they hatch and perhaps become another creature’s food source in the process. 

Adding birdhouses specifically to attract blackbirds will help keep grasshopper populations down before they get out of hand. Bat boxes are also great, as bats eat moths, gnats and mosquitoes while we sleep.

Step 3 
Determine your limits

The next step to managing pests is to determine how much damage you can tolerate. As a home grower, I don’t mind eating spinach with chew holes from flea beetles. Professionally, I can’t tolerate any damage since my customers buy with their eyes. 

When plants are young in the spring, I have a very low tolerance for damage and will intervene immediately. I’m more lenient at the end of harvest because frost is coming and investing time and money into my plants is less important.

Step 4 
Traps, lures and biological controls

Bug zappers are effective for cabbage moths, and I use a lot of yellow sticky cards fastened to chopsticks when leaf miners or fungus gnats show up. Little bowls of stale beer attract slugs and don’t leave a chemical residue in the garden.

Biological controls are the most fun option; however, I once released ladybugs in my back yard and they migrated to my neighbor’s rose bushes, which had more aphids than my garden. 

You can purchase an army of beneficial insects at www.soundhorticulture.com

Bacillus thuringiensis (Bt) is a beneficial bacteria that acts as a biopesticide on beetles, black flies and moths. It’s toxic to problematic nematodes in the soil, but it’s non-toxic to humans.

Step 5 
Use sprays

This option is the most expensive and takes the most time to manage. 

I make my own pesticide by soaking chopped chili peppers, garlic and onion in a quart of water overnight. Strain it and add 1/4 teaspoon of liquid dish soap for clinging power and spray it on crops. 

I’ve also sprinkled crushed chili pepper powder on plants right after spraying them. The powder sticks to the leaves, which deters rabbits. Remember not to spray basil or lettuces the day before harvesting so you don’t get the taste.

If I do purchase a pesticide from the garden center, I only choose products with an OMRI label. This means the Organic Materials Review Institute in Oregon has verified that it’s non-toxic to humans. 

Sprays are really my last option because pesticides are not target specific. They kill all bugs regardless of how beneficial they are. Insects also build a resistance to sprays, so a pesticide that works great this week can be ineffective after a month of continued use. 

If you resort to using sprays, make sure to rotate. That keeps the problematic insects on their heels—or heading over to the neighbor’s yard!

For help with identifying pests, call CSU Extension Master Gardeners at 970-244-1834.