17 Pro Tips for Managing Garden Pests This Summer

From dreaded aphids to fat hornworms and nasty potato beetles, summer brings a hoard of pests eager to munch on your edible crops. Conventional mindsets aim to spray away all the bugs, killing everything in their wake, but this can often do more harm than good.

If you kill all the bugs in your garden, the harmful pests are the first to return. The “good guy” insect predators struggle to recuperate, resulting in an endless cycle of chemical applications. On the other hand, ecological gardeners work with nature rather than against it. 

Believe it or not, pests can be messengers to inform you about the health of your crops, soil, and your yard’s entire ecosystem. Pest outbreaks are signals from nature that something is out of balance. Instead of killing all the bugs, we can think from a holistic perspective to address the root causes of insect pressure. Professional ecological growers use integrated pest management (IPM) techniques like monitoring, companion planting, and biocontrol (predator insects) to keep the “bad bugs” at bay.

Let’s dig into 17 pro tips for managing summer garden pests without toxic chemicals.

How Do I Manage Summer Garden Pests Organically?

Summer garden pests can be controlled organically with row fabric, diverse insectary plantings, neem oil sprays, hand removal, Bt applications, diatomaceous earth, slug traps, chickens, ducks, and insect netting.

Biological control is the best long-term solution to manage pests without pesticides. Also known as biocontrol, this nature-mimicking technique aims to attract beneficial predatory insects. These predators eat pests like aphids, spider mites, whiteflies, cutworms, earwigs, leafhoppers, and even mosquitoes. 

Attracting predatory bugs involves planting or installing the proper habitat for them to breed and overwinter. Flowering insectary patches, beetle banks, duck ponds, bat boxes, and interplanting are some of the most effective methods for building up beneficial insect populations in the garden. 

However, creating an ecosystem of biocontrol does not happen overnight. It requires several seasons to establish a fully functioning population of predatory insects.

17 Pro Tips for Managing Garden Pests

Summer’s warm weather and long days are amazing for plant growth, but they also bring a lot of unwelcome visitors. Insects are the most major pests of edible crops, emerging from spring dormancy only to munch down on all your baby plants. 

Aphids, slugs, cabbage moths, leaf miners, earwigs, and cutworms are some of the most common pests. Flea beetles, spider mites, tomato hornworms, and Colorado potato beetles are other major attackers of summer veggies. While each pest has its own lifecycle and crop targets, there are many control options that can enhance the overall pest management across the garden.

Use these methods individually or in combination for less pests and more abundant harvests!

Cover With Row Fabric

Row cover is one of the quickest and easiest ways to deter pests. It is a physical barrier that doesn’t require any chemicals. This thin agricultural textile allows sunlight and water in but keeps flying pests out. It is perfect for “floating” over young seedlings to help them establish themselves without the pressure of hungry pests. The fabric also enhances heat near the base of the soil to speed up germination and growth in cooler seasons.

Sometimes, pests can get trapped in the fabric, so I prefer to use row covers only in the early stages of plant growth. It is amazing for keeping flea beetles away from radishes, turnips, bok choy, arugula, and baby brassica greens. It can also alleviate transplant shock in cold-tender crops like zucchini or cucumbers. However, once crops begin flowering, you must lift the cover to allow pollinators to access the blossoms.

The main drawback is that row fabric is synthetic. The woven fibers are usually made of polyester or polypropylene. However, if you take good care of the material, it can last for 5+ seasons. Avoid using landscape staples or anything that might put holes in the fabric. Sandbags, smooth rocks, or padded clamps are great options for securing the covers without puncturing the material.

Use Diluted Neem Oil

Neem oil is one of the most popular and effective organic pest sprays. This oil comes straight from the smelly seeds of the neem tree (Azadirachta indica), an evergreen tree that grows in subtropical and tropical areas. The oil has a deep yellow color and a very strong odor reminiscent of sulfur or garlic. The natural ingredients, like azadirachtin and sialin, kill pests without harming your plants.

Neem oil sprays are best used for major infestations. They rapidly kill soft-bodied insects. It is very important to dilute neem oil in water before applying it because the concentrated oil can burn plants or skin. Morning or evening applications are ideal because the sun is less harsh, and pollinators are not as active. While this is an easy option, there are even better ones to use before spraying down your plants.

Harness the Power of Biocontrol

Let nature do the pest management for you! Biological control, or biocontrol, is the science and art of using natural predators to control pests. Ladybugs eat aphids, lacewings eat mites, and parasitic wasps attack tomato hornworms, but how do we get these beneficial bugs into our gardens?

Classical biocontrol involves introducing store-bought bugs into your garden. This method is really only recommended for closed-system greenhouses. It also has relatively short-lived results. Since most of us are gardening outside, conservation biocontrol is much more reliable. 

Conservation biocontrol involves creating a long-term habitat for bugs to take up residence in your garden for many generations and seasons to come. As you build up beneficial insectary habitat, pest control becomes easier and easier over time. 

First, Stop Applying Pesticides

The most crucial rule of establishing a biocontrolled garden is: You cannot apply broad-spectrum pesticides! Broad-spectrum chemicals kill all bugs, including the “good guys.” In order for conservation biocontrol to work effectively, the insects must be left to establish their populations without chemical interference.

Sometimes, this causes more pest outbreaks in the beginning, especially if you have sprayed pesticides in the past. Those pesticides build up in the ecosystem due to a phenomenon called bioaccumulation. Predatory insects like ladybugs eat thousands of aphids per day. If each aphid was exposed to even a small amount of pesticides, you can imagine how much more concentrated the chemical becomes once it’s inside the ladybug.

You may need to employ non-chemical pest management techniques like row cover and insect netting to help alleviate the pest pressure while your garden adjusts to a spray-free biocontrolled method.

Next, Plant Insectary Areas

Once you stop killing beneficial predators, you must attract more of them to the garden. Nobody wants to live in a place without proper resources. Like humans, beneficial insects need a place to sleep, eat, drink, and raise their young. Planting insectary areas is the best way to create a habitat for predators.

Insectaries are semi-wild and planted areas rich with a diversity of native flowers and vegetation. Don’t worry; this doesn’t mean these areas must be unkempt! Insectaries can be very beautiful. The key is to avoid over-manicuring the areas. Spider webs, lacewing cocoons, and ladybug eggs need a place to safely establish. Too much mowing, pruning, or manual disturbance can prevent these predators from creating generational homes. 

Aim for dense plantings of native flowering plants. Predator insects need a combination of nectar, plant matter, and pollen resources. Some of the most effective species include:

Avoiding pesticides and planting insectaries are the most important steps to welcoming more biocontrol agents to your backyard.

Grow Diverse Plantings

Research shows that diverse plantings are one of the best pest management tools. A diversity of crops makes it harder for pests to find their host plants and to leap from one plant to another. Sometimes called polyculture, a diverse planting involves medleys of many different crops. In contrast, a monoculture involves growing a bunch of the same plants in a single space. 

Most of us naturally grow polycultures in our gardens because we want to enjoy a diversity of foods. However, we can take this management strategy to the next level by incorporating more diversity in individual beds and sections of the garden. Better yet, we can plant multiple varieties of each crop to increase the diversity of plant shapes and genetics. Remember, biodiversity equals more resilience! 

How Diversity Reduces Specialist Pest Pressure

If you are searching for a particular item, it is much easier to find it in a big group of similar things. For example, finding a specialty hiking boot is much easier in an outdoor store than in a supermarket. Moreover, the boots would be extremely easy to find in a store that only sells hiking equipment or specializes in hiking boots. This analogy perfectly explains why specialty pests are attracted to clusters of host plants. 

Specialty pests are bugs that specifically attack a certain family or species of plant. For example, cabbage loopers specifically eat brassicas (cabbage-family crops). Similarly, squash bugs specifically attack cucurbits (squash-family crops). In contrast, generalist pests, like aphids or spider mites, will attack a broad range of different plants. Generalist pests are more difficult to control because they will eat practically anything. 

Sprinkle Your Crops Around to Confuse Pests

You can deter specialist pests more easily by diversifying plantings. For example, instead of planting a giant bed of tomatoes, you can scatter clusters of tomato plants in different parts of your plot. Interrupting the concentration of plant species confuses the pests.

Take it to the next level by interplanting tomato beds with peppers, marigolds, lettuces, and basil. This strategy makes it difficult for specialist pests to find the host plants and leap from one plant to another. Tomato hornworms (hawk moths in adult form) will struggle to find tomatoes when they are interspersed amongst lots of other plants.

Enlist a Chicken (or Duck) Army

Hand-plucking pests is a gross and time-consuming task. Why not hire some feathery friends to do it for you? Backyard chickens or ducks are some of the best pest controllers available. These hungry birds will scrounge up annoying pests and help loosen the soil in the process.

However, it’s important to keep chickens or ducks contained in certain areas. They can scratch up your vegetables and destroy greens like lettuce or spinach. This pest management method is best used in between crops. In other words, you can use chickens or ducks to clear out a crop when you are done harvesting it. Their manure will also fertilize the soil for the next round of plants.

For example, I like to release chickens into expired beds of salad mix. They ate the remnants of the greens while removing any slugs or cutworms from the soil below. Raised beds are helpful because the chickens usually stay close to the ground. Portable electric fencing is useful to keep the chickens away from your valuable, actively growing crops. 

Grow Vertically

Raised beds, containers, and vertical planters are awesome ways to physically deter pests from your crops. Many soil-dwelling pests hang out low to the ground. These pests thrive when the native soil has been disturbed by tillage or compaction or if it is colonized by grass and weeds.

A raised bed allows you to grow in quality, microbially-rich soil that nurtures the growth and immunity of your crops. Healthier crops are less desirable to insect pests. Moreover, the complex soil food web ensures that dirt-dwelling pests are more likely to be devoured by natural predators before they can wreak havoc on your crop roots.

Growing above the soil level also improves drainage, reduces weed pressure, and reduces back aches. No more hunching over to tend your crops! Better yet, the wooden or metal sides of a raised bed make it easy to attach hoops or clamps to secure row cover, greenhouse plastic, and insect netting.

Sprinkle Diatomaceous Earth

Diatomaceous earth (DE powder) is a unique powdery substance made of fossilized remains of ancient aquatic organisms called diatoms. The skeletons of those ancient organisms were predominantly made of silica. The silica deposits are microscopically sharp, so they penetrate the exoskeleton of slugs and fleas, causing these harmful insects to dehydrate and die.

You can use diatomaceous earth in your home and yard to deter and kill pests. It works great to kill fleas in outdoor chicken coops or dog kennels. It must be sprinkled around crops on the soil surface. Some growers also apply it to the leaves, but you should be careful not to cover too much of the leaf surface because it could impede photosynthesis. DE powder must be applied in dry weather and sprinkled carefully in the exact location where it is needed.

Use Insect Netting

Insect netting is the best pest-deterrent fabric for hot-climate growers. It physically keeps bugs out, but unlike row fabric, it doesn’t retain heat. The netting can actually add a little bit of shade to keep crops cooler during scorching summers.

This insect barrier allows light and water to pass through but keeps bugs out. The netting and mesh materials come in many sizes for different pest types. The finest mesh keeps almost every type of bug out, including gnats and no-see-ums. Similar to the insect mesh used on screen doors, the material is flexible and amenable to a diversity of settings. 

The main downside of insect netting is its tendency to get tangled. It can also blow away in the wind if you don’t properly secure it. I prefer to drape it over hoops and secure it with clamps.

Plant Beetle Banks

Beetles are underrated predators of garden pests. While Colorado potato beetles, Mexican bean beetles, and flea beetles are common pests, predatory beetles like ground beetles, ladybugs, and assassin bugs are highly beneficial.

Predatory beetle species feed on aphids, earwigs, mites, caterpillars, grubs, fly maggots, and mealybugs. They can even eat soil-dwelling slugs and snails! But these voracious pest-eaters cannot do their job in overly manicured landscapes. Beetles need a place to hide, overwinter, and breed.

Beetle banks are strips of native grasses that provide habitat and shelter for overwintering beetles. If you plant native perennial grasses along the margins of your garden, beetles can find a safe haven and offer long-term biocontrol. As a bonus, many native grasses are ornamental and attractive. 

Beetle banks often include logs and leaves for the beneficial invertebrates to hide out. When the resident predatory ground beetles and spiders get hungry, they crawl out of the beetle bank to scour your garden for pests like aphids and midges. Beetle banks also provide overwintering areas for beneficial ground-dwelling bees.

Hold Off On Mulching

Mulch is one of the best weed-suppressing tools we have as gardeners. However, pests sometimes hide out in the cozy, dark moisture of mulch. If you have problems with earwigs and slugs, it’s best to wait to mulch your plants until they are established.

Mulching in the spring often creates a welcome habitat for slimy pests to hang out while they munch on your crops. When you wait to apply mulch in early summer, the weather is usually dryer and less welcoming.

Mulching too early can also smother newly germinated seedlings and young crops. It is best to wait to mulch your crops until they are 6-12 inches tall. For example, let corn germinate in open soil and grow to a sturdy stalk before you apply mulch around the base. This makes it less likely for pests to attack the young plants. 

Practice Companion Planting

Companion planting isn’t just a garden trend; it really works! When you grow certain plants together, they offer mutual benefits that reduce pest pressure, improve pollination, and suppress weeds. White alyssum, marigolds, and creeping thyme are just a few of the most effective companion plants for vegetable gardens. 

As a commercial organic farmer, I never planted a row of strawberries or tomatoes without white alyssum or marigolds interspersed among the crop. Companion planting is ridiculously easy as long as you consider the spacing and growth habits of both plants. 

For example, white alyssum grows low and spreads like a ground cover, making it the perfect complement to shrubby plants like strawberries as well as tall plants like tomatoes. Similarly, French marigolds stay fairly compact, so they won’t compete with peppers or tomatoes. Instead, they attract pollinators, suppress root-knot nematodes, and improve overall crop performance.

However, you must be aware that not all companions are beneficial. You don’t want to plant fennel next to lettuce because fennel can release root compounds that suppress plant growth. Similarly, zucchini and spinach are a bad combination because zucchini plants grow very large and sprawling, likely smothering the spinach. Moreover, zucchini is a warm-weather crop, and spinach is a cool-weather crop.

Matching the right companions becomes easier as you understand each plant’s size, seasonality, and growth needs. This video explains a few popular science-backed companion combos that really work:

Avoid High-Nitrogen Fertilizer

Excessive nitrogen fertilizer can cause a lot of major problems in the garden. You may think that nitrogen will boost your plant growth, but you can have too much of a good thing. Synthetic nitrates are particularly problematic because they add mega-doses of quick-release nitrogen to the soil. Heavy rainfall can leach these nitrates into waterways, harming aquatic organisms. For your plants, the nitrogen excess can actually cause more pest problems. 

Aphids and other sap-sucking insects can actually sense when a plant has a lot of nitrogen in its leaves. Big doses of nitrates cause an overgrowth of leafy vegetation and a concentration of plant sugars at the expense of flowers and fruit. This big vegetative burst attracts more sap-suckers to the leaves of your plants. Aphids proliferate rapidly on plant sap that is loaded with nutrients. 

The best way to prevent this phenomenon is to use balanced, organic fertilizers. Organic, slow-release nutrients are less likely to cause a big spike in plant sap nitrogen. Your plants will also funnel their energy into a healthy balance of leaf growth, root growth, and flower/fruit development. Look for organic fertilizer products with NPK ratios that are close together, such as 3-4-4.

Install Bat Boxes

Mosquitoes don’t attack our plants, but they can certainly make gardening miserable for humans. Most people don’t realize that bats are the number one best predators of mosquitoes. If you want to avoid spraying harmful deet or pesticides, consider installing bat boxes. Bat boxes are simple wooden structures installed on tall poles or trees. Similar to a birdhouse, they attract native bats to make a home in your yard.

These bats are nocturnal, so they’ll never bother you during the day. More than half of global bat species are also severely declining, so you can aid in recovering endangered animals. The bats hunt at night, consuming thousands of mosquitoes as well as moths, cucumber beetles, and leafhoppers.

You can buy a premade bat box or learn to build your own from Bat Conservation International.

Use Bt for Brassicas

Bacillus thuringiensis, or Bt, is a soil-dwelling bacteria that is toxic to caterpillars. It is one of the most popular sprays for brassica crops. If your kale, cabbage, broccoli, cauliflower, or Brussels sprouts are constantly being attacked by cabbage loopers (larvae of the white cabbage moth), this solution is quick, easy, and organic!

Bt is purchased as a spray or biological pesticide. It degrades in the sunlight, so it must be applied to brassica plants in the evening. The best thing about Bt is that it doesn’t harm non-target organisms. In other words, it is a highly specific pest control method that only kills caterpillars. Be sure to follow all package instructions and avoid overapplications.

Use Slug Bait and Traps

Slugs are only a spring issue in dry areas, but in moist climates like the Northeast, these slimy pests can be problematic throughout the summer. Conventional slug bait uses metallic substances that are toxic to wildlife. However, organic slug baits like ferric phosphate or beer traps specifically harm slugs and snails.

You can purchase organic slug bait in pellet form and scatter it around effective crops. The slugs eat the bait and die from the ferric phosphate, but the ingredients are not harmful to other wildlife. 

You can also install beer traps, which lure slugs into sunken trays at the soil level. Slugs apparently love beer just as much as people, so all you need to do is fill a shallow tub with beer, bury it at ground level, and let the pests fall to their drunken death so they avoid eating your plants.

Try Trap Crops

Trap cropping is a semi-effective method for deterring pests away from your crops. Basically, a trap crop like nasturtiums or radishes is planted nearby to lure in the pests. When the pests attack the trap crop, you destroy it to cut back on populations.

The biggest mistake gardeners make with trap cropping is forgetting to kill the trap crop. If you leave the trap crop for too long, it actually becomes a breeding ground for more pests to colonize your garden. You must pull the crop up, spray it with neem oil, and throw it away to prevent the spread of the pests. 

Timing and monitoring are crucial for this method, so be sure you are up for maintenance before trying it.

Hang Sticky Traps

Last but not least, we can’t forget good old-fashioned sticky traps! These hanging yellow traps are popular amongst house plant growers, but they also work great in greenhouses and gardens. Sticky traps physically trap flying insects on a sticky paper surface. Flea beetles and gnats are magnetized to the bright yellow color, but then they get stuck and die.

You can hang sticky traps on trellis systems or above greenhouses to monitor pests. Unfortunately, beneficial insects like bees, butterflies, or ladybugs sometimes get trapped on the sticky surface. Use these as a last resort, and avoid hanging these traps near flowering plants.