Home gardening: How to identify and control garden pests
Ferry-Morse Home Gardening Blog | July 2021
A group of aphids eating away at a ripening green tomato.
Abundant flowers and green leaves that suddenly show signs of decline can be stressful and disheartening. After all, seeing your plants healthy and thriving provides a sense of peace, relaxation, and accomplishment.
The sheer amount of advice, methods, and products to handle pests can be overwhelming. Trust me. You're not alone. This article is going to cover some simple solutions to your home garden pest problem.
Identify what's attacking your plants.
A garden pest can be an insect, pathogen, or weed. Let’s focus on the first two.
Here's an interesting fact: Most insects are beneficial or harmless.
Many beneficial insects perform valuable activities in the garden, such as pollinating fruits and vegetables and producing desirable products like honey. Insects also prey on each other, helping to maintain balance in their populations.
Harmful insects comprise less than one percent of the more than one million species of known insects, but they receive the most attention. They feed on plants by chewing, rasping, or sucking leaves, stems, flowers, and fruits.
A quick visual inspection—that includes the undersides of leaves—should reveal damage caused by insects. Look for trails in leaves, chewed edges, holes in fruit, skeletonized leaves, and frass.
Sooty mold is another sign of infestation. Fungi love to grow on the sweet honeydew secreted by aphids.
A close-up of a plant leaf that has been eaten away at by insects.
Pathogens are infectious, contagious organisms comprised of bacteria, fungi, viruses, and nematodes. Damage caused by pathogens presents physically as discolored leaves, powdery mildew, lesions, oozing, spots, galls, dropping leaves, and abnormal visual patterns.
Keep in mind that if every leaf on a plant is discolored, it might signify a nutrient deficiency, like the yellow leaves caused by iron deficiency.
It's also important to know that insects often spread pathogens from plant to plant. With that in mind, it's best to have an integrated approach to pest management. Let's dig a little deeper.
Red zinnias in bloom, their foliage is suffering from powdery mildew.
How do I fix my garden pest problem?
Home gardeners have many choices when it comes to pest control. Let's take a closer look at a research-based method.
Integrated Pest Management (IPM)
IPM is an environmentally sound, science-based method to control pests. Visualize it as a pyramid.
Implement good cultural and sanitation practices.
Cultural and sanitation practices form the foundation of the IPM pyramid. It involves preparing the soil, selecting pest-resistant plants, and applying water and nutrients correctly.
Install mechanical controls.
Row covers, traps, deterrents, and other mechanisms help control insects, like destructive squash bugs.
Strawberry plants growing in an outdoor garden, their tops are covered with a mesh-like cap to prevent insects from getting to their foliage, stems and fruits.
Use biological agents.
Biological control takes advantage of natural enemies to control pests. Organisms, such as beneficial arthropods, predatory mites, and parasitic wasps, suppress many pest problems, even the infamous hornworm.
Take advantage of pesticides.
In IPM, pesticides form the smallest part of the overall plan.
Use pesticides as a reactive rather than a proactive form of pest control. After all, seeing our precious vegetables covered in garden pests is alarming! It might prompt you to spray the infestation immediately with a pesticide to get rid of them.
Despite best efforts, we can find ourselves in a never-ending battle against insects so numerous that treatments with pesticides are necessary. When you must go this route, be sure to read and follow the directions on the label because the last thing you want to do is create a toxic environment for humans and good bugs.
What are everyday pest control products and related garden pests?
Here's a brief walkthrough of some standard garden products.
Bacillus thuringiensis (Bt) is a widely available pest-control microbe. Spray it on a severe infestation of caterpillars, such as cutworms.
Diatomaceous earth is composed of a naturally occurring substance called silica, a key component of glass. It's sold as a bag of non-poisonous dust that kills insects, slugs, and snails through dehydration.
Horticultural oil can be applied to vegetable plants and fruit trees. Soft-bodied insects, fungi, and bug eggs are most affected. It's a classification for a variety of natural and synthetic products. Synthetic oils are produced from petroleum products, whereas Neem oil, a great organic option for powdery mildew and spider mites, occurs naturally.
Insecticidal soap can be a commercial product or soapy water you make at home. It kills soft-bodied pests but doesn't affect the good guys of the bug world, like ladybugs and others whose bodies are hard. This soap is an excellent solution for severe infestations of scale insects and whiteflies.
Milky spore is a bacterial agent that will kill the larvae of Japanese beetles, which look like a smaller metallic June bug and eat leaves down to their veins.
Restore your tranquility with your new abilities.
Gardening is an enjoyable activity, but it does have its challenges. With a bit of knowledge and practice, you can overcome them easily.
When you're ready to take the next step in your gardening journey, try planting these pest-deterring varieties around other plants in your garden: