Pest Control in an Organic Garden

Once you decide that you are going to grow organically, you will need to figure out how you will deal with pests in your garden using organic pest control.  Many gardeners that grow a conventional vegetable garden are used to grabbing a chemical and doing a quick treatment of their plants when they spot pests. This is a bad idea that will make the problem worse in the long term.  When you use a broad-spectrum pest control method, like a chemical spray or insecticide powder, you kill all the insects that encounter it. 

Not only does this harm your beneficial insects, but it also creates an environmental ‘hole’.  The environmental hole is almost always later filled with insects, and they usually aren’t the insects that you want.  Pest insects are notoriously the first insects to return to fill the hole, creating an endless cycle of using pesticides.

Beneficials or Pests?

Conventional gardening and pesticides can create numerous problems.  Organic gardening requires you to be more hands-on with your plants.  The first step to organic pest control is to closely monitor your plants.  Get in the habit of looking over your plants twice a day. Take note of what kinds of insects you see.  Do you notice beneficial insects like ladybugs and hoverflies? Are there pest insects like squash bugs or hornworms?  If you are not familiar with which insects are good and which ones are pests, you will not know whether you need to take action or not.

There are many beneficial insects that will flock to your garden.  Some are pollinators, which are necessary for proper fruit production.  Everyone is familiar with the honeybee and bumble bee, but they are just a drop in the bucket when it comes to beneficial insects.  There are some beneficials that will keep pest bugs off your plants.  These bugs are predators and will eat the harmful insects so that you do not have to worry about them.

Tip: The EASIEST and fastest way to identify pests in the garden? Use our app From Seed to Spoon. You'll find photos of beneficial insects and pests so you can easily compare the types and make your plan.

Here is a short list of some common beneficial insects:

• Pollinators like butterflies and bees
• Ground beetles
• Praying mantis
• Hoverflies
• Assassin bugs
• Robber flies
• Green lacewings
• Spiders
• Ladybugs

Pest insects are ones that cause harm to your plants.  They may chew up leaves or fruit, or they may cause some other form of damage to the plant.  The pests that you will have to deal with will depend on where you live.  Some gardeners in the south report having the most trouble with tomato hornworms while gardeners in out west may have more trouble with potato beetles.  The method of attack for pests will depend on the pests that you are dealing with.  It is important to know that your insect is actually a pest before trying to eliminate it.  

Common garden pests include: aphids, asparagus beetle, blister beetle, cabbage root maggot, cabbage worm, carrot rust fly, potato beetle, corn earworm, cucumber beetle, cutworms and armyworms, flea beetle, Japanese beetle, Mexican bean beetle, slugs and snails, squash bug, squash vine borer, tomato/tobacco hornworm, and whiteflies.

Some pest insects are plant specific, while others are not picky and will attack multiple plants.  Learn how to identify pests from beneficials.  It is equally important to understand the insect’s life cycle.  If you understand how the life cycle of a pest insect works, it’s easier to break that cycle to reduce your pest problems. 

For example, the cabbage moth is a small white moth that resembles a butterfly.  As an adult, it’s a beneficial insect and works to pollinate plants in your garden.  However, it lays its eggs on plants in the brassica family.  These eggs hatch to become the pest cabbage worm.  If you notice cabbage moths fluttering around your garden, you may want to cover your cruciferous plants before they can lay eggs on them.

Herbs, Flowers, and Birds are Your Friends

The easiest way to control pests in your garden is to ask for help.  There are many plants and organisms that you can invite to your garden that will help reduce your pest load.  Obviously sending out invitations will not work, so how do you create an environment that is anti-pests?

Start by planting herbs and flowers in your vegetable garden.  Herbs and flowers can work to benefit your garden in two diverse ways:

1. Some plants will put off chemicals that can keep pests away.  A frequently used example of this is the marigold. Marigolds are often touted as a wonderful companion plant because they release chemicals that can help keep pests away. 
2. Other plants work to attract beneficial insects. Any plant that flowers will attract pollinators, which is always a good thing.  But some flowering plants will also attract non-pollinating beneficials that will eliminate pests. Plants like borage and nasturtiums will not only bloom for pollinators, but they will also attract predatory insects that will feed on pests.

Plant some of the following plants in your vegetable garden to help with pest control: nasturtium, cosmos, dill, borage, yarrow, alyssum, zinnias, thyme, rosemary, mint, calendula, cilantro, and marigold.

You will also get help with pests if you attract wild birds to your garden.  You can do this easily by putting up bluebird houses.  Bluebirds feed insects like grubs, slugs, and soft-bodied bugs to their young.  They will pick any soft-bodied pests right off your plants to make a meal for their babies.  Sparrows are another bird that is highly effective at removing pests from the garden. 

Some people despise house sparrows, but they are one of the most effective birds when it comes to pest control.  Flycatchers are also very adept at removing pests, including pests that will bother you, like mosquitoes.  Encourage birds to spend time around your garden by setting up bird houses, feeders, and bird baths.

If you have domestic birds, like chickens, ducks, or guinea fowl, you can get their help to control pests.  Ducks are one of the best pest control methods that gardeners can have.  They will pluck all sorts of insects off your plants, and they are especially good at getting large worms like tomato hornworms, slugs, cabbage worms or cut worms off plants.  A couple of domestic ducks can remove tons of bugs from your garden and turn the pests into nutritious eggs for you.

Chickens can also be used to control insects in the garden.  Chickens will grab beetles, worms, grasshoppers, and many other bugs right off the plants.  If you allow your chicken in the garden, make sure that you are supervising them.  Chickens can also make an easy meal of small vegetables and young plant shoots.

Natural Pest Control Methods

Not all pest control problems can be solved without your intervention.  From time to time, you will have to use some form of pest control.  There are a few options that are still organic and environmentally friendly.

The first step to controlling pests is to remove them by hand if you see them.  When you go out to the garden, have a pail filled with insecticidal soap handy.  Pests can be plucked off by hand and dropped down into the soap.  This is effective because it not only removes the insect from your plant, but it prevents that insect from reproducing.  Breaking the life cycle of the pests is a very effective way to reduce your pest loads.

Not only can you attract beneficial insects to your garden, but you can also purchase them and release them into your garden.  This is an inexpensive way to get targeted control of certain pests in your garden.  If you are having issues with aphids, consider purchasing ladybugs to release into the garden.  Ladybugs are voracious predators that can consume hundreds of aphids per hour.  You can find many different predatory beneficials through greenhouse supply stores online.

Diatomaceous earth is a white, chalky-feeling powder that you can use in your garden to help with pests.  Diatomaceous earth is made from the tiny, fossilized remains of microscopic creatures called diatoms.  The fossilized remains of the diatoms have sharp, jagged edges.  When soft bodied insects walk or move across the diatomaceous earth, they are cut open and will die.  You can sprinkle diatomaceous earth around your plants to prevent slugs, worms, and other pests from reaching your plants.  It is a good control method that will create a barrier around your plants while still allowing your pollinators to reach the plant. 

There are also a few options for chemical control that are organic and environmentally friendly. Some commonly used and very effective chemical controls include Bt (Bacillus thuringiens) sprays, neem oil, horticultural oil, insecticidal soap, and garlic-pepper spray.  Bt sprays can be effective against many soft bodied insects like hornworms, cutworms, and cabbage worms.  Neem oil is very effective against some of the hard-bodied pests like beetles and squash bugs.

Employing these methods of pest control into your garden will create fewer pest problems in the long term and will help to create a healthy, more natural, organic vegetable garden.