This post may contain affiliate links. As an Amazon Associate, and at no cost to you, I earn from qualifying purchases made through some links. Please see FCC disclosure for full information. Thank you for supporting this site!

Not all bugs are bad. In fact, some bugs are so good, you can practically see their halos; they enrich your soil (like worms and centipedes do), eat pests that harm your plants (ladybugs, dragonflies, and spiders, for instance), and pollinate your plants (hello, bees and moths). Even "bad" bugs are tolerable if there aren't too many of them...in fact, several scientific studies show that vegetables lightly eaten by pests are actually more nutritious to eat. However, when pests start increasing in number, they can completely destroy your garden. 

A few generations ago, the answer to any bug problem was to buy a man-made chemical and spray it everywhere. However, now we know this not only kills the bad bugs, but it kills the good bugs, too. Besides, who wants to grow their own food just to end up eating a bunch of pesticides? ("Cide" means "killer" in Latin, you know.) 

The good news is, organic methods of pest control are extremely effective. It's just a matter of knowing how to use them. 

Prevention is Key 

The number one best way to deal with pests in the garden is through prevention. There are several basic ways you can reduce the risk of pests attacking your crops: 

* Make great soil. If your soil is full of organic matter and well-balanced nutrients, your plants will be strong and better able to fight off pests. To ensure your soil stays in tip-top condition, do a yearly soil test and amend accordingly, add organic matter (such as manure, compost, dry grass clippings, and dry leaves) at least once a year, ideally in the late fall; this gives the amendments time to break down and enrich the soil before spring planting. 

Organic gardening is absolutely attainable.

* Rotate crops. To keep the soil healthy and help break the cycle of pest egg-laying, crop rotation is important. For example, if you plant broccoli in one spot in your garden this year, you should not plant broccoli or anything in the broccoli family in that spot for the next three years. For the purposes of vegetable crop rotation, there are only six families of plants: 

1. Alliums: Like garlic, leeks, and onions. 

2. Brassicas: Like broccoli, Brussels sprouts, cabbage, cauliflower, collards, kale, mustard greens, radishes, and turnips. 

3. Cucurbits: Like cucumbers, melons, summer squash, and winter squash. 

 4. Legumes: Like green beans, peas, and peanuts. 

5. Nightshades: Like eggplant, peppers, potatoes, and tomatoes. 

6. Umbellifers: Like carrots, dill, fennel, parsley, and parsnips. 

* Encourage wild birds and beneficial insects (that eat bad bugs) in your garden. Give birds safe places to nest and consider putting out feeders. Encourage good bugs by planting flowers that attract them in or around your vegetable garden. 

 * Observe your garden daily. Look closely for any changes to plants, and check under leaves and on the soil for any signs of pests or disease. Catching problems early is a major key to success in gardening. 

<{>Slugs and Snails 

Garden slugs are one of my great nemeses.

 

On summer evenings, I can step out onto my porch and literally hear the slugs and snails chowing down on my plants. It's not an exaggeration to say we have millions of slugs and snails on our homestead, both native and non-native. Fortunately, there are many organic ways to prevent them from completely destroying our garden. 

Whenever possible, I hand pick slugs and snails. I go out early in the morning - or even just after dark - and pick all the slugs and snails I see, putting them in a bucket. (You can also lay down a piece of plywood or some wood boards the day before and then turn them over in the morning to find slugs and snails hiding under them.) When I'm done picking, I sprinkle ordinary salt over the critters to kill them. (I don't recommend salting slugs and snails directly on the soil because salt builds up over time and will prevent plants from growing.) 

If you have small numbers of snails, you can simply crush them with your boot; larger slugs can be dispatched by poking a stick through their bodies.

For small gardens, copper tape, which shocks slugs and snails, can be applied to pots or raised beds. However, if even one leaf grows over the copper tape, slugs and snails will use that pathway to get to your plants. Since copper tape can be pricey, I typically use other methods. 

Beer traps, for example, are relatively inexpensive (use the cheapest beer you can find) and quite effective. Lay out empty tuna cans, upside-down Frisbees, or similar shallow containers, pour a bit of beer in them, and in the morning you'll find slugs and snails have drowned themselves in the brew. Rinse and repeat. 

Recent studies by Oregon State University, however, find that bread dough is the very best way to attract and kill slugs and snails. Just mix together 1 cup of flour, 1 packet (about 2 1/4 teaspoons) of yeast, and about 2 cups of water. If the mixture isn't liquidy, add more water. (OSU calls this mixture a "slurry.") Pour the mixture into empty plastic containers, such as clean, empty sour cream or cottage cheese tubs. Dig a shallow hole in the garden - just big enough that the container's rim is about level with the soil. Place the container inside. Check this trap daily, removing pests and refreshing the slurry as needed.

Banana slugs may be cool-looking, but they are garden destroyers!

But even given these useful methods, we have so many slugs and snails that I find myself needing to sprinkle iron phosphate (which occurs naturally in the soil and is best known under the brand name Sluggo) around the garden when my plants are at the vulnerable seedling stage. When applied according to the directions on the package, it is "relatively non-toxic" to pets, children, and wildlife, according to the Oregon State University Extension Office. (This means they'd have to eat a lot of it to get sick.) It can withstand some rain and irrigation before it needs re-applying. 

If slugs and snails are a problem for you, you'll also want to avoid two common gardening practices: Drip hoses and larger wood bark mulch. Slugs and snails love both. (On the other hand, many people swear pine needle mulches repel these pests.) 

Some gardeners swear by food-grade diatomaceous earth (DE, for short) for slugs, snails, and any pest with an exoskeleton. This readily-available powder is made from the ground up bodies of fossilized algae. There are a few drawbacks to DE, however. One is that it only works when it's kept dry, so if it rains, or you irrigate, it will require reapplication. DE is also irritating to eyes and dangerous to breathe in, so you need to pour it out with care - ideally wearing a mask and goggles. Worse, DE kills bees. To help keep the bees in your garden alive and buzzing, you should never apply DE to flowers; in fact, avoid applying it anywhere but the soil. Reduce the risk to bees even further by applying DE at dusk, when bees aren't flying around - and only when there is no wind. 

In my experience, crushed eggshells work just as well against slugs and snails, but as soon as water splashes earth onto them, they become much less effective. (Both DE and eggshells work by being painful for slugs and snails to slink over.) 

Finally, you might want to consider getting ducks and allowing them to roam your garden. Ducks love eating slugs and snails! The only trouble is, they will eat your desirable garden plants, too, so they are best used when the garden is dormant. For example, you could allow ducks into your garden in the late winter and early spring, when they will eat pests and gently fertilize the soil, then move them to a different area before planting your spring garden.

Incidentally, if you don't realize you have a slug problem until you harvest your veggies (the slimy suckers are famous for hiding in the inner leaves of cabbage and Brussels sprouts, for example), place the veggies in a clean sink and cover them with water. I use a dinner plate to hold the veggies down, and after a few minutes, all the slugs have crawled out of their hiding places. Most end up on the dinner plate, but a few others will be on the sides of the sink. 

Aphids 

A bad aphid infestation.

These tiny, clustering pests literally suck the life out of plants, so at the first sign of aphids, kick them off with a blast of cold water from the spray nozzle of your hose. This will often completely take care of the problem, but in the days following, do check under leaves to make sure new aphids don't appear. If the aphids are attacking only one or two leaves, I prefer to simply cut off those leaves and feed them (and the aphids) to my chickens. (Alternatively, you could secure the affected leaves in a sealed plastic or paper container, then throw them away.) 

If aphids still persist, organic neem oil is an excellent solution. (Not all neem oil products are organic, so read labels carefully.) Avoid spraying the oil on a windy day; you want to keep it out of your eyes and lungs. Like many pest control solutions, neem oil will have to be re-applied if it rains or you use a sprinkler. To apply it, simply spray it all over the plant, including under leaves. If you don't want to buy neem oil, you could use a homemade spray. These are usually soap based (a common recipe is 1 quart of water and 1 or 2 teaspoons of liquid dish soap), but these should be used with caution because sometimes they burn plants, especially if applied on a sunny day. Like neem oil, these soap-based sprays work by suffocating aphids. 

You could also try buying and dispersing a natural predator of aphids, such as ladybugs or lacewings. In my experience, however, this isn't always successful; these predators may fly away, leaving aphids behind on your plants. I suggest you first ensure you have plenty of plants to attract these predators (for example, ladybugs love dill, carrots, fennel, and yarrow). This will help keep purchased predatory insects in place - and it will attract wild ones, too. 

Cutworms 

Black cutworm. Courtesy of USGS.

If your seedlings look fine one day, but then are suddenly chopped off at soil level the next day, cutworms are likely to blame. Fortunately, you can stop cutworms in their tracks by using cutworm collars. You can purchase these collars at gardening centers or you can make your own from a plastic drinking cup (cut the bottom out and put the seedling inside), a toilet paper roll (cut into three-inch lengths and plant the seedlings in the center), or even rings of aluminum foil. (I've always used aluminum foil, but this year I used toilet paper rolls and found it easier and just as effective.)

Cabbage Worms 

Cabbage worm. Courtesy of the U.S. Dept. of Agriculture.

If you find small, green worms on your brassicas, you can try hand picking them off and then either squishing them or killing them in soapy water. You can also soak affected harvested veggies in salt water, which will make the pests crawl out of their hiding places and drown. 

But if you want to prevent cabbage moths in the first place, place row covers over your brassicas. Just make sure you do this as soon as your garden is planted in the spring, or the pretty white moths (whose children are cabbage worms) will have a chance to lay their eggs in your garden. Another trick that some people swear by is planting orange-flowering nasturtiums in amongst your brassicas. 

Truly, these steps should take care of cabbage worms, but if you find yourself in the midst of a huge infestation, you could also bring in the big guns: biological pesticides. These include Bt (Bacillus Thuringiensis, a natural soil bacteria that's toxic when ingested by insect larvae) or spinosad (a natural substance made by soil bacteria that's toxic to certain insects). Spinosad is less desirable because it may harm aquatic invertebrates and earthworms; it must also be applied at dusk so it has a chance to dry before bees are exposed to it. These pesticides are organic, but really should only be used when other measures don't do the trick. 

Grasshoppers 

A few grasshoppers are pretty harmless, but lots of them are devastating. Courtesy of Jean and Fred Hort.

Who can forget the vivid image On the Banks of Plum Creek, Laura Ingalls Wilder's autobiographical novel, gives of a grasshopper plague? "Grasshoppers beat down from the sky and swarmed thick over the ground..." Wilder wrote. "The air whirred and the roof went on sounding like a roof in a hailstorm. Then Laura heard another sound, one big sound made of tiny nips and snips and gnawings...The grasshoppers were eating...You could hear the millions of jaws biting and chewing..." And then, when they had eaten everything in sight: "All across the dooryard the grasshoppers were walking shoulder to shoulder and end to end, so crowded that the ground seemed to be moving. Not a single one hopped. Not one turned its head. As fast as they could go, they were all walking west." 

Fortunately, most gardeners don't have to worry about invasions like this. Still, even a few grasshoppers can definitely damage our plants. The good news is, just as Laura learned, chickens love eating grasshoppers. So do guinea fowl, geese, and ducks. So if you spot a large number of grasshoppers in your garden, your poultry friends should be able to take care of them. 

It's also smart to encourage grasshoppers' natural predators (such as wild birds, toads, lizards, and small snakes) to take up residence in your garden. For example, you could make sure there are some slightly elevated areas with plenty of foliage for toads to hide under, build a ditch or small pond for water, and make a toad house that sits nearby. 

In addition, DE and neem oil can help protect plants against grasshoppers, as can sticky traps, and Beauveria Bassiana, a natural - through pricey - fungus that kills certain insects, including grasshoppers, termites, thrips, whiteflies, and aphids. Even though this fungus is generally considered safe for beneficial insects, it should be used only as a last resort, as it does have the power to kill bees if the fungus ends up on flowers. 

Squash Bugs 

A common type of squash bug. Courtesy of Christina Butler and Wikipedia Commons.

These critters can absolutely devastate your cucurbit crops, and many people find them quite a difficult enemy. Hand picking squash bugs off plants and then squashing them is an effective method (although not an easy task, since cucurbits are so viney). It's also vital to interrupt the bug's life cycle so they don't persist in your garden. Make sure you clean up all plants at the end of the season, burning rather than composting them. And while thick mulches are recommended for most gardens, squash bugs love them, so they must be avoided if you have issues with these pests. 

You can also spray neem oil on any egg clusters you find (or simply scrape off the eggs with a butter knife or cut off and dispose of affected leaves). Row covers are also a helpful ally in fighting squash bugs; put them up as soon as you plant cucurbit seeds or seedlings and only remove them when the first female flowers appear. As summer progresses, predators who love to eat squash bugs (including bigeyed bugs, damsel bugs, and feather-legged flies) tend to come out in full force, so consider not planting any cucurbits until early summer. 

Squash Vine Borers 

Squash vine borer. Courtesy of NY State IPM Program at Cornell University.

Using crop rotation is essential if squash vine borers are a problem in your area; choosing resistant varieties may also be necessary. These resistant varieties (which include Eight Ball, Tatume, Poquito, Cucuzzi, Butternut...anything in the Cucurbita Moschata family) have thick, solid stems that repel borers. In addition, long-vined, open-pollinated summer squashes will fare better than hybrid varieties (because they develop additional roots wherever the vines touch the soil; if borers attack the plant, you can cut off the affected parts and still keep the squash alive). 

Planting squash later in the season and then keeping a row cover over it until you begin seeing female flowers, is also effective. If all else fails, Bt sprayed onto the main stem of the plant (but never the flowers) should do the trick; see the section on cabbage worms for more information on Bt. 

Cucumber Beetles 

A common striped cucumber beetle. Courtesy of Katja Schulz and Wikipedia Commons.

The main issue with this pest is that it transmits bacterial wilt to cucurbit plants; there is no effective treatment for this wilt, so affected plants will die. 

Handpicking (using rubber gloves smeared with Vaseline) vacuuming (with a handheld vac), sticky traps, neem oil, and making sure to remove and burn all plants from the garden once they are spent, are helpful practices. Putting row covers over seeds or seedlings until the first female flowers appear is also highly effective, as is planting in early summer, instead of spring, when the pests are making themselves known in the garden. 

Also, if you till your garden in the spring, be sure to let your poultry - especially chickens and guinea fowl - follow behind you. Cucumber beetles burrow under the soil during winter's cold conditions, but tilling brings them up where your poultry can use them as a tasty meal. 

Japanese Beetles 

Japanese Beetle. Courtesy of Ryan Hodnett and Wikipedia Commons.

If you live where it's very hot or very cold, Japanese beetles shouldn't be much of a problem in your garden. Elsewhere, however, removing the pests by hand and then squishing them (or dumping them in a bucket of soapy water) is an effective method of control. Although traps are available for Japanese beetles, they may not be as effective as you wish. 

Letting your chickens, guinea fowl, geese, or ducks into the garden to feast on these bugs can put an abrupt end to an infestation. The best way to do this is to allow your birds into the garden in late spring, when Japanese beetle larvae are close to the surface of the soil. In addition, using row covers at the right time of year is helpful. In the southern part of the U.S., put them up 8 weeks before mid-May; in the North, 8 weeks before mid-June. Just note that row covers keep out pollinators, too. 

Hornworms 

Tomato hornworms. Courtesy of Mike Lewinski.

The very best way to get rid of hornworms is to pick them off by hand and then either squish them or dump them in soapy water. However, sometimes they are very good at hiding! If that's the case, use a blacklight to spot them; it will make the pests light up brightly. 

Hornworm damage.

 

Ants 

Generally, ants are more of a nuisance to the gardener than an actual pest to plants; although you might see ants crawling on your veggies, they are after honeydew (the sweet excrement of certain pests, like aphids), not the plants themselves. 

However, if ants have a nest in an inappropriate place in your garden, a very easy way to get rid of them is to use Borax (a naturally occurring mineral which you can find in the laundry aisle of grocery stores). Borax is considered safe to use around pets and children, but since large quantities could make them sick, it's a good idea to watch both to ensure they don't eat the bait. 

There are two tricks to using Borax as ant killer. The first is to correctly mix it with an ingredient that appeals to ants. Most ants are attracted to sugar, so the most common recipe is to mix equal parts of borax, warm water, and granulated sugar. If this doesn't seem to attract your ants, try equal parts of borax and peanut butter instead. 

The second trick is to put the bait in the correct location. If you can see a line of ants marching, put the bait (placed on a plastic lid) at the beginning or end of the line. If you can see the ant's nest, put the bait there instead. The ants will eat this mixture, take it back to their nest, and die. 

Fire ants are a whole different problem. They may not harm plants, but they can surely cause gardeners pain! Spinosad (as discussed in the section on cabbage worms) is highly effective against fire ants if it's applied directly to their mounds and set out as bait. 

Finally, Be Vigilant! 

Even though organic methods of pest control are effective, often gardeners make the mistake of not being vigilant enough. Keep checking your garden daily. Re-apply sprays or powders or granules as needed. Keep gloves, a bucket, and dish soap handy in the garden to make hand picking easier. Don't neglect to hand pick every time you see a pest. (I assure you, there are plenty more pests you don't see, so you needn't be afraid of depriving wildlife of food.) 

Small problems can lead to much bigger ones, and the best way to ensure insects don't destroy your garden is to be an alert watchman.

Related Posts: