8 Simple Steps To Rid Your Vegetable Garden Of Pests – Without Using Chemicals

There is nothing more rewarding than growing vegetables that will nourish your family. Yet, it is incredibly frustrating to put in so much hard work, only to discover that the local pest population has obliterated your prized crops.

Pests in vegetable gardens range from the tiniest aphids to mammals and birds – all requiring different solutions.

It’s more difficult to fix a pest problem once it’s started than it is to prevent damage in the first place. Once the problem has gotten out of hand, it is tempting to reach for chemical control solutions. However, these can also kill beneficial insects and harm wildlife. Chemicals will stay in the soil for months, or even years, harming the biodiversity of your garden.

Follow our 8-step pest-proofing plan using natural, organic methods so you can focus on what really matters: growing the most delicious crops.

1. Get To Know Your Enemy

First, it pays to understand how to identify common pests. Prevention is always the best medicine, so you need to know what you’re dealing with.

These are some of the most common critters that wreak havoc on veggies in the garden and signs typical of their damage:

• Aphids. These small insects will feast on any vegetable. They pierce and feed on leaves, leaving behind honeydew that can cause sooty mold. Look for tiny aphids on the undersides of leaves and a sooty powder.
• Cabbage moth. The larvae and caterpillar of this moth leave ragged holes between the veins of leaves, mainly on brassicas.
• Colorado potato beetle. Once more common in the west, this beetle has spread east, feeding on potatoes and other nightshade vegetables. Look for damaged leaves and yellow egg clusters under the leaves.
• Cucumber beetle. These pests feed on all types of cucurbits. Look for leaf and flower damage and scarred fruit.
• Squash vine borer. The larvae of this moth feed on the insides of stems of squash and pumpkins causing wilting. Also look for holes in stems just above the soil line.
• Tomato hornworm. These are green caterpillars that feed on tomatoes and nightshades. They will remove entire leaves from plants. You should also be able to spot the caterpillars and their droppings.
• Slugs and snails. Slugs and snails feed on many plants. Characteristic signs are rounded holes in the centers of leaves and shiny slime trails.
• Birds and mammals. Insects are more numerous, but birds and mammals can do a lot of damage. They eat all kinds of vegetables. Some burrow underground and eat roots and tubers.

2. Block Out Pests With Fencing And Netting

When pest-proofing a vegetable garden, your first step should be to protect it from bigger animals that will do the most damage in a short amount of time.

The best way to prevent damage from birds and mammals is to set up barriers. The bigger the pests, the sturdier the barriers need to be.

Tall vegetable garden fencing or chicken wire is ideal for larger animals such as deer. This needs to be at least 8 feet (2m) tall. Simple deer mesh or single-strand electric fences both work well.

To keep rabbits out of gardens, shorter fencing will suffice. Aim for 2 to 3 feet (61-91cm) tall, but bury the fence up to 6 inches (15cm) under the ground. This also works for other burrowing animals, such as gophers.

Use bird netting over plants with edible fruit to keep birds from getting to your harvest. The nets can simply be draped over trees, canes, or other plants. However, this makes it difficult to harvest the fruit. Instead, erect supports around the plant and drape the netting over it, then secure it to the ground with soil staples.

3. Encourage Beneficial Insects

Keep pests at bay naturally by attracting beneficial insects that prey on them. Predatory insects like ladybugs, lacewings, hoverflies, and parasitic wasps feed on many soft-bodied pests that damage vegetables.

Limiting, or ideally eliminating, pesticides is a vital way to support these beneficial predators. It's worth bearing in mind that many gardeners have used chemical pest control, only to find they have eradicated beneficial insects while the pests have survived.

Grow plants that attract them. Their favorite flowering plants include mint, daisy (Shasta and Oxeye), wild carrot (Queen Anne's lace), cosmos, marigold, and clover. However, generally speaking, including a good number of native plants will help to boost their numbers.

Buying beneficial insects is another option to increase populations. It’s easy to find ladybugs for sale, for example. You can even source praying mantis eggs, but bear in mind they will eat other beneficial insects along with the pests.

4. Deter Pests With Companion Plants

Companion planting is the ancient practice of pairing plants that benefit each other. When used on the vegetable plot, companion plants work to keep pests away from your crops.

Marigolds, with their strong smell, are a good example. They put off rabbits and deter cabbage moths from your brassicas. Other fragrant plants that pests don’t like include rosemary, chives, onions, basil, and catnip.

Flowering companions can also help by attracting predator insects, like wasps. Plant flowers that attract pollinators between rows of vegetables to draw in beneficial insects.

5. Protect Crops With Row Covers

Row covers serve many purposes, including keeping pests off plants. They provide a barrier to cover plants susceptible to insect damage. Look for row covers made from a lightweight, breathable woven material to allow sunlight and water through.

Pollination is a potential issue with row covers because beneficial pollinating insects cannot get to the flowers. However, you can minimize this by limiting their use to key times. Employ row covers early in the season to keep insects from laying eggs, and then again after flowering is finished to protect plants from damage to leaves and fruits.

6. Trap Slugs and Snails

You’ll never keep slugs and snails out of your yard, but you can keep them away from your vegetable plants by making a simple DIY slug trap. This uses small, flat boards with runners to keep them an inch (2.5 cm) or so above the soil surface.

Moisten the soil beneath the boards before laying them down to entice the slugs. Place them under the targeted plants, between garden rows, or anywhere evidence of their presence has been noticed. Every morning, check under the boards for slugs or snails and scrape them into a bucket of soapy water.

Another option is to make a beer trap, which tends to work better for slugs than snails. Use a shallow dish buried partially into the soil near the plants you want to protect. The sides of the dish should be low enough for the critters to climb in. Fill the dish with beer. The slugs and snails will be attracted to the smell and crawl into the dish overnight.

7. Apply Neem Oil Early

Neem oil is a natural pesticide available in any garden center. You can buy it ready to use or as a concentrated solution that needs to be diluted.

Often used once pests have already attacked plants, it can be beneficial in deterring pests and managing early infestations. As it prevents pests from eating and growing, it is most effective when insects are in their immature stages.

Neem oil works on soft-bodied insects, which includes many common vegetable garden pests. Spray the product all over plants until they are well covered. Bear in mind it may take several applications to see results.

Neem oil is safe, but wash vegetables and fruits before eating them.

8. Protect Plants With Diatomaceous Earth

If you have plants at particular risk of crawling pests, then surround them with a ring of diatomaceous earth (DE).

DE is the fossilized remains of single-celled sea creatures. It is a powdery material that dehydrates and kills soft-bodied insects on contact. When used in the garden, pests will either avoid it or crawl over it and become dried out.

Be aware that, although natural, DE does kill beneficial insects too. Use it sparingly and take care not to inhale it.

Only use food-grade DE sold in garden centers. Other types of DE, including a product used in pool filters, can be very harmful to inhale or ingest.