Japanese beetles
Iridescent, jewel-toned Japanese beetles may be beautiful, but they can inflict hideous damage on your garden, where they devour blossoms and leaves seemingly overnight. At the first sign of attack, use a neem-oil-based insecticide, which is relatively harmless to birds, mammals, and plants.
Related: 9 Best Buys for a Bug-Free Home
Aphids
These tiny, sap-sucking insects feed on all plant parts, from roots and stems to petals and leaves. They reproduce rapidly, making it easy for an aphid infestation to spread throughout your garden. Discourage them by planting resistant flowers like marigolds and lavender.
Related: 10 Plants to Grow for a Pest-Proof Yard
Colorado potato beetles
Don’t be fooled by the name—the Colorado potato beetle is a major pest throughout North America, not just in the Rockies. These yellow-orange, 3/8-inch-long bugs will feast on your tomatoes, peppers, eggplants, and (of course) potatoes. Neem oil can help prevent an infestation.
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Cutworms
Larva-stage Noctuidae are particularly voracious. They earned the name cutworm because they gnaw on stems below the soil, cutting down young plants in their prime. Surround stems in diatomaceous earth to protect against these hungry caterpillars.
Related: 8 Things the Exterminator Won’t Tell You for Free
Wikimedia Bee Inventory and Monitoring Lab from Beltsville, Maryland, USA [Public domain]
Squash bugs and squash vine borers
Zucchini and other squash are garden favorites because they grow rapidly and produce high yields. But beware of squash bugs and squash vine borers, two different species that attack the entire plant. Early detection is essential, so be on the lookout for yellowing and wilting leaves.
Wikimedia Commons: Judy Gallagher [CC BY 2.0 ]
Flea beetle
This common pest chews irregular holes in plant leaves and has a fondness for radishes, broccoli, cabbage, turnips, eggplant, peppers, tomatoes, potatoes, spinach, and melons. Use yellow sticky traps to catch flea beetles before they spread.
Slugs
If your garden has resident slugs, you'll notice the glistening trails and see big bite holes around tender young shoots. Slugs can eat their way through spring bulbs, hostas, lettuce, asparagus and many other plants and flowers. Diatomaceous earth and slug and snail bait can help control the problem.
Whiteflies
Tiny, sap-sucking whiteflies are a problem for both indoor and outdoor plants, which wind up weakened, with wilted, yellowing leaves. Use neem oil and sticky yellow traps to decrease damage.
Rose slugs

Not slugs at all, these sawfly larvae will skeletonize rose leaves from spring through fall. To control, spray roses with spinosad, a natural by-product of soil bacterium that can be toxic to insects.
Related: 12 Fast-Growing Shrubs to Plant This Fall
Wikimedia Commons via Beatriz Moisset
Grasshoppers
In the wake of warm, dry weather, large populations of grasshoppers can infest domestic gardens, stripping plants of leaves, flowers, and any hope of bearing fruit. Be proactive by planting flowers like marigolds, daisies, and alyssum, which attract bugs that will attack grasshoppers. But accept that grasshopper swarms are difficult to control, even with insecticides; protective plant covers may be necessary.
Keep The Pests Away

With bugs in the garden, your best offense is defense.
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