2817 - 47th Street • Moline, IL 61265 (309) 762-6226

We’ve yet to meet a gardener who hasn’t dealt with pest damage or disease at some point. We can’t always keep our plants out of harm’s way when there’s a hungry insect or wandering spore around every corner. Luckily, by staying informed on Moline’s “most wanted” (or rather, least wanted!) pests and diseases, we can plan ahead to keep our garden plants safe. Here’s our guide for troubleshooting plant pests and diseases.


Identifying Garden Pest Damage

While you may not be around to catch garden pests in the act, you’re sure to find some clues that will help you catch the culprit! Identifying garden pests by leaf damage is the simplest way to plan your counter-strike. Here’s how to identify the most common garden pests in Moline.

Culprit: Japanese Beetle
Clues: Hopefully you aren’t too familiar with Japanese beetles already, who destroy entire yards over the course of their lifespan. The larvae feed on grass roots, creating patches of brown, weakened lawn. The adults, meanwhile, feed on leaf tissue between the veins, leaving leaves looking like skeletons of their former selves.
Control: These tough-shelled pests are notoriously tough to control, but we’ve finally found a great solution to carry at our garden center. Optrol™ is a broad-spectrum pesticide that is effective at controlling Japanese beetles. One application is effective for a season, so we recommend a spring, summer, and fall application.

Culprit: Aphids
Clues: Shiny, sticky spots on leaf surfaces along with wilting, discolored leaves.
Control: Optrol™is also effective against aphids, but if you only have a minor aphid infestation, you can control them with a solution of water and dish soap mixed in a spray bottle. Apply twice daily until you stop noticing aphids. If the solution doesn’t seem to be working, you can also try a neem oil solution.

Culprit: Cucumber Beetle
Clues: Your plant leaves—especially cucurbits—are covered in holes and developing a yellow color, and your seedlings are getting completely devoured. You may also notice pockmarks on your fruit and veggie crops.
Control: These black-and-yellow beetles are voracious eaters, but the real risk is that they’re also carriers of plant diseases. Planting tansy and nasturtiums around your cucumbers has a natural repellent effect, and sticky traps are a great way to booby-trap your plants without using chemicals. Protect seedlings with row covers until they’re old enough to pollinate.

Culprit: Leaf Beetles
Clues: Leaf beetles are more of a class of beetle than a species. Like Japanese beetles, leaf beetle species devour the tender bits of the leaf between the veins. If the leaves look skeletal but the lawn looks fine, it’s likely some sort of leaf beetle causing the damage.
Control: Hand-picking beetles seems to be the best method. Pick them off the plant and throw them in a bucket of soapy water to kill them. You can also apply neem oil or insecticidal soap to discourage beetles from sticking around, but avoid applying them to edible plants.

Culprit: Cutworms
Clues: Severed stems, normally low to the soil.
Control: Diatomaceous earth is great for controlling cutworms. They get around by crawling, and the product has tiny jagged particles that cut them up when they walk on it.


Plantskydd troubleshooting pest fungal damage moline


What About Non-Insect Pests?

If the damage you’re noticing looks like it was caused by something much bigger, you’re going to want to try something else! We carry a fantastic product called Plantskydd® that humanely controls virtually all plant-eating mammals. Plantskydd® is a repellent product that naturally keeps animals like deer, squirrels, chipmunks, rabbits, hares, and voles out of your garden.


Troubleshooting Fungal Damage & Infection

Warm, humid summer air turns your garden into an ideal environment for fungus to thrive. To prevent fungal infection, make sure to keep plenty of air flow low to the soil in your garden and avoid over-watering. Sometimes, however, disease strikes anyway. Here’s how to identify the most common fungal diseases in Moline gardens:

Culprit: Blights
Clues: Blight takes a few forms. Early blight looks like brown or yellow patches in a “bulls-eye” pattern on leaves, and late blight looks like mysterious grey and white patches of dead tissue all over the plant.
Control: Remove the affected area immediately and destroy it—don’t throw it in the compost! Finish by covering the area around the main stem with fresh compost or soil. Prevent blight by aiming water at the soil and not the leaves. Fungicides can be an effective preventative treatment if you have an ongoing issue with blight.

Culprit: Damping-off
Clues: This disease affects seedlings and is characterized by the seedling collapsing and dying off.
Control: Always plant seeds per the package directions, with proper spacing and depth, to prevent damping off. Appropriate watering and sunlight also helps to give seedlings their best start.


meyer CTA


Culprit: Blackspot
Clues: The name about sums it up. Black spots appear on the leaf surface, with many leaves also turning yellow. The disease will eventually affect the stems and kill the plant if uncontrolled. Roses are susceptible to black spot.
Control: Remove all affected areas of the plants as soon as possible, and rake up and destroy any fallen leaves. Proper air flow and ground-level irrigation can also help prevent blackspot from developing.

Culprit: Powdery Mildew
Clues: While powdery mildew makes your plant leaves look like powdered sugar donuts, it definitely isn’t sweet. It’s a type of mold that makes plants look dusty.
Control: Prevention is the best medicine for this fungus. Keep your garden nice and neat by cleaning up fallen debris and trimming plants back to promote air flow. If powdery mildew is a consistent issue, try a seasonal application of an appropriate fungicide.


Insects and fungal diseases can threaten the health and appearance of your plants, but if you catch them in time, most plants are resilient enough to recover. Help your plants defend themselves naturally against disease and pest damage by keeping them well fertilized and appropriately watered all season long.


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