Cheap ways to protect your plants and garden from pests

Garden pests can be extremely annoying and can ruin our careful planting and care in one vicious blow.

Whether you grow indoors or outdoors, prevention is often better than cure.

Here are DIY measures I regularly use in my small urban garden to keep pests at bay – without spending a lot of money or using chemicals.

Build healthy soil to create pest-resistant plants

First, create an environment that makes your plants more resilient so they are less likely to be attacked. This literally starts from the bottom up, by creating healthy, living soil.

Whether you grow in pots, raised beds or directly in the ground, focus on feeding the billions of beneficial microbes that live in the soil. These good guys work symbiotically with plants, allowing roots to absorb and deliver more nutrients immunity against diseases and pests.

Simple ways to feed microbes in your soil:

• Add compost and old animal manure regularly.
• Mulch with bark chips, straw or green manure – or, for a free version, ‘chop and drop’ weeds (before they go to seed) by cutting the base of the stem and allowing the leaves to slowly rot.
• Make your own liquid ‘weed’ tea fertilizer by soaking weed plants in water for a month or two, then diluting the resulting liquid and watering your garden.
• Supplement garden beds with ‘no-dig’ layers, alternating carbon-rich materials (like fall leaves) with nitrogen-rich materials (like manure) in lasagna-like layers.
• Buy biofertilizers enriched with living microbes.

Use simple barriers to exclude pests

The second tool in your prevention kit is simple barriers that prevent pests – even possums, birds and rats – from attacking your plants or vegetables.

Gauze is the easiest option; even a second-hand gauze curtain will do. Just make sure it is nature friendly with a mesh size of 5 mm or less, so that birds and bats are not caught and killed.

Nets can also repel cabbage moths and whiteflies, which plague brassicas such as broccoli and kale. And you can create barriers to slugs and snails by spreading coffee grounds around the seedlings, or you can purchase wool pellets as a natural deterrent.

At my home I have collected old wire baskets, free of roadside rubbish, and placed them over young seedlings to protect against birds (including my escaped chickens) and rats in the crucial first weeks.

Paper or mesh bags placed over fruits such as tomatoes or apples and then tied with string also help keep birds at bay.

And a tip for houseplants: fungus gnats lay their eggs in houseplants top few inches of moist soilSo make that environment inhospitable by watering from the bottom of the pot.

Encourage beneficial insects

In permaculture, a common approach is to do absolutely nothing if you notice pests descending on your garden. Real!

Common garden pests will soon be eaten by beneficial insects if you wait just a week or two for them to arrive. Ladybugs and lacewings, for example, like to eat aphids. Learn to identify the main insects in your garden so that you recognize the helpers and don’t accidentally kill them.

If you’re short on beneficial insects, your garden ecosystem is telling you it needs more diversity. So plant flowers to attract more insect friends, especially Australian natives and exotics such as yarrow, feverfew, chamomile, sweet alyssum and Queen Anne’s lace.

You can even buy live beneficial insects online and release them into your garden for an instant insect control boost.

Mix up plantings to confuse pests

Instead of planting neat rows of one thing — which creates a monoculture smorgasbord that pests can systematically work their way through — plant vegetables, herbs and flowers all in one bed.

The tangle of diversity confuses pests and can also help plants grow better if you have the right knowledge companion mix right.

Strongly scented plants such as nasturtium, thyme, oregano, marjoram and sage can also help repel certain insects.

And check out the seasonal planting guides for your climate zone to see what to plant and when. For example, evergreens planted in the summer are more likely to struggle — and the pests will move in to cull an unhealthy plant.

Sprays can also affect beneficial insects

If the infestation is so bad that you simply have to take action, remember that even certified organic sprays can kill the good bugs as well as the bad ones.

Instead, try removing pests with your fingers or spraying them away with a garden hose. Consider setting simple traps, such as a shallow container of beer for slugs and snails, or compostable adhesive pads for fungus gnats.

For severe infestations, the best remedy may be to completely remove the affected plant and throw it in your community’s green bin. Then get started on building up your soil life so that you can grow a healthier plant next time.

The effect of these simple methods is cumulative, as I have noticed in the permaculture garden in my backyard. With each passing year, the number of pest visitors gradually decreases as my garden ecosystem begins to fend for itself.

Koren Helbig is a freelance journalist who practices permaculture and grows organic food in the backyard of her small urban home in Tarntanya (Adelaide).