Natural Pest Control

Integrated Pest Management

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Natures Way

Many vegetables grow well with other plants in the garden and, using a few basic principles, organic gardeners can really have nature on their side in the biological control of pests.

How can you control pests and diseases naturally?

The best way to control plant diseases is to prevent them occurring in the first place. This can be achieved with healthy cultivation methods:
Choose plants that match your garden’s conditions and are pest-resistant.
Water to encourage strong root systems and avoid humid conditions. That is infrequent deep watering in the early or late part of the day. Less water on the surface means roots have to search.
Add organic matter to soils as manures, composts and mulches - to encourage microbes that attack plant pathogens and to supply nutrients to plants keeping them vigorous and healthy.
Use seaweed and fish emulsions to boost the plant's immunity to pest and disease attack.
Fertilise to strengthen plants eg. ensure plants have adequate potassium (promoting thick cell walls).
Plant to encourage predators and plant decoys to distract pests. For example mulberries encourage wasps and hibiscus will distract stink beetles from citrus,
Try some companion planting.

The most commonly documented companion plants repel pests when planted alongside vegetables. Other plants attract pest predators to the vegetable patch. Some plant roots secrete substances that repel pests or provide nutrients to the plants around them. These plant interactions can work in specific ways between two or three types of plants or species. See the companion planting guide attached.

Peas and Beans add nitrogen to the soil.

Legumes (peas, beans, etc.) trap nitrogen from the air with nodules on their roots. When these crops have finished producing you can dig them into the soil so that the nitrogen is available to the next crop. Being leafy vegetables, the brassica family (cabbages, broccoli, etc.) require a lot of nitrogen to grow, so it makes sense to follow summer pea crops with winter cabbages that can use this free nitrogen source.

What if pests still invade?

If pest levels do become unmanageable by natural means, you should consider the environmental impact of the pest control measures you employ. Non-synthetic organic chemical means are by far the preferred option.

Home Remedies

Pest control solutions listed below can be made from ingredients commonly found around the home. They are less toxic than many commercial preparations; to the soil, other organisms and you, the user. Before employing the pest control, consult the list of preventative controls.

Pest	Preventative control	Spray/ Trap	Preparation	Note
Fruit fly	Pick up fruit fall (break breading cycle, companion plants	1/4 teaspoon of vegemite 1cup of water neighbouring the on you want to protect.	combine and pour it into a plastic drink bottle. Make some holes in the side and use some wire to hang it in trees	You need to hang lots of traps to maximize the impact and it's important to remember to empty and replace traps weekly
Cabbageworm, leafhoppers, and whitefly	Companion plant, attract wasps and other predators.	3 cloves of finely chopped garlic 2 teaspoons of vegetable oil, 1 tsp dish washing liquid, 1 lt water.	Finely chop garlic and soak in oil for about 24 hours. Strain this mix then add 1 teaspoon of dishwashing liquid and 1 litre of water to the oil.	Mix it well and spray regularly for best results. Be aware, the mixture of oil and detergent can burn some plants. Always test the lower leaves of plants first to make sure they aren't affected.
Root knot nematode	Add lots of organic matter to the soil and use crop rotation. Companion plant with Marigolds	Molasses has been extensively trialed and found to be a very effective deterrent	Simply dissolve 1 litre of molasses in 4 litres of warm water, allow it to cool and use it to drench the soil.	This is a quick fix when needed
Scale, Aphids, Mites, Young Grubs or Preventative for Citrus Leaf Minor	Feed soil, strengthen foliage health with compost tea, fish emulsion, worm wee, comfrey tea etc. Companion plant. Manual squashing, avoid killing natural predators, hose aphids off leaves	100g chopped garlic bulbs 2 teaspoons vegetable oil 2 teaspoons liquid detergent ½ litre water	Soak garlic in oil for 24 hours. Mix detergent with water and add to the garlic mixture. Stir well, strain into a lidded glass jar, label as an insecticide and refrigerate. To make up the spray, dilute 5ml of mixture in 1 litre of water. Spray directly on to the pest	It's important to avoid using it in very hot weather (over 25 deg) because it can burn foliage.
Sap-Sucking Insects (aphids, lacebugs, bronze orange bugs, leafhoppers and whitefly)	Feed soil, companion plant, diversity, foliage feed sprays. Pick off diseased leaves.	10 grams grated soap 1 litre of water	Simply measure grated pure soap or soap flakes and dissolve it in a litre of warm water. Pour it into a spray bottle, give it a good shake and spray it all over the insects.	Do it 3-4 times every 5 days to put a stop to big infestations. Do it late in the day when temperatures are cool to avoid leaf burn.
Snails	Attract predators, remove hiding places (pots/ bricks with holes etc.) Snails don’t like to get their foot dirty! They tend not to travel over some substances such as: Shell grit, Hair cuttings or, Sawdust Sprinkle them around the base of seedlings and other snail delicacies to keep the snails out. Normal mulch.	Place saucers of beer near seedlings and other plants that are susceptible to snail attack. The snails are attracted to the smell of the beer.	They consume it, become drunk, fall into the saucer and drown. Use margarine containers with slippery sides.	Poisoning snails is poisoning the food chain and you may just kill a blue tongue lizard.
Cabbage Moth	Companion plant, scattered planting, not in rows, attract predators such as wasps and birds. Manually squash caterpillars. Manual squashing. To stop cabbage moths laying eggs on your veggie seedlings, scatter empty eggshell halves amongst your cabbages, broccoli, brussel sprouts and any other crops that get eaten by cabbage moth caterpillars. These territorial moths mistake the eggshells for other cabbage moths and leave the area.	Chilli Garlic Pyrethrum
Weeds	The best way to control weeds is to out compete them. Ensure healthy soil and multilayered gardens so there is no room for weeds.	Boiling water will kill weeds if you pour it directly onto them. Take care not to get the water on the plants you want to keep in your garden though, as it will affect those too. This method is especially useful for paving cracks if all the plants between the pavers are weeds. Vinegar will kill couch grass.
Blackspot on Roses	Decrease humidity around plants hygiene is important. That means you need to diligently remove infected material by hand, and pick up any diseased foliage that is lying around on the ground. Dispose of this in the centre of a hot compost.	1 litre skim milk 1 litre soapy water or (preventative) 4.5 litres of water 3 level teaspoons of bicarbonate soda 3 tablespoons of fish emulsion	Stir the liquid to completely dissolve the bicarbonate powder. Spray it 3 times over 2 weeks to get on top of the problem then follow up with a weekly application saturating the plant each time.	NEVER spray in full sunshine or in the heat of the day as the leaves may burn. Instead wait until early evening.
Fungal infections: Powdery Mildew, down mildew, rust etc.	Decrease humidity around plants	4 teaspoons bicarbonate of soda 50 ml white oil 4 litres water Full-cream milk sprayed onto the affected leaves will kill the fungus.	Spray foliage as required.	recent research suggests that potassium bicarbonate, rather than the kitchen variety bi-carb of soda is much more efficient.
Ants	Control scale or aphids that ants are attracted too. Plant mint to deter ants.	Boiling water poured between pavers.

Some gardeners have found Molasses useful in repelling certain leaf chewers such as caterpillars. In this case, dilute 2 tablespoons of molasses in a litre of warm water and spray it on the foliage regularly.

IMPORTANT NOTE - Please take care with spraying and storing these preparations, especially with regard to children and pets. The strength of ingredients varies noticeably particularly in regard to garlic. These home remedies are designed to have a minimal impact on the environment, but no solution that is intended to kill should be regarded as safe. When storing solutions keep out of reach of children and clearly label.

Natural Pest Control In The Home

Natural pest control, also known as integrated pest management, aims to use the least toxic methods to repel, control and eliminate pests. It includes; monitoring the pest population, identifying the behaviour and homes of the pests, modifying habitats, repairing and installing structural barriers, removing food sources through improved inside and outside sanitation, and applying the least toxic approach to getting rid of the pest.

Ants

Observe where the ants are coming from and block their entrance, gap filler or duct tape work well, use soapy water to kill the ants and wipe out their trails.
To repel use drops of orange essential oil, a line of cinnamon powder or mix it with water and squirt into gaps, scatter leaves of pennyroyal, spearmint, or slices of cucumber. Pour left over tea leaves on pot plants.
To repel rub a cut lemon over ant tracks, or wherever ants are a problem.
To kill mix 3 cups water and 1 cup sugar with 4 teaspoons of borax, place in dishes along ant trails, refresh every couple of days. * NOTE: Borax is a natural occurring mineral salt BUT is poisonous when swallowed, not recommended for use in homes with children and / or pets.

Cockroaches

Screen windows and doors, seal up cracks and crevices and don’t leave food scraps lying around. Ensure all cupboards and other dark places are thoroughly dry.
To repel wipe benches, floors, shelves, cupboards, drawers, bin, etc with a mixture of 100ml water to 10 drops of eucalyptus oil. Wipe straight eucalyptus oil around drain holes and external door frames.
Place cucumber peelings and / or bay leaves in cupboards where cockroaches are a problem. Replace when dried out.
Cockroach traps. Grease the rim and top 2 cm of a container (round margarine containers work well), with bacon fat or butter / margarine.
Place a banana peel or bacon scraps inside and leave overnight in an infested area. Coackroaches will crawl in but can’t get out because of the grease.
Soak a rag in beer and place in a shallow dish overnight in an infested area. In the morning you can dispose of the drunken cockroaches and silverfish
Cockroach baits. Mix together equal parts of borax (*see note on borax) and sugar and place in lids wherever cockroaches are a problem, will last up to 1 year.
Mix 2/3 cup of mashed potato (boil potato in water and mash in its own juice) with 1/3 cup of baking powder, roll into marble sized balls and place in cupboards. Cockroaches will eat the balls and gas will build up in their guts from the baking powder / potato mix. Because cockroaches can’t burp, their stomachs explode and they die.

Cats

To repel place orange peel cut face up near your plants. Mix 10 drops of lavender oil and/or 10 drops of eucalyptus oil in 200mls of water and spray on mulch and rocks in the garden as needed.

Dogs

To repel mix 10 crushed garlic cloves with 1 tablespoon of cayenne or 1 teaspoon of Tabasco in 4 cups of warm water, steep for 2 hours then strain into spray bottle and use where needed (may also be used to repel cats and possums).

Fleas

To repel, grow mint, fennel and wormwood in the garden or in pots on the veranda. Place mint, fennel and wormwood leaves (separately or a mixture of) under rugs, mats, sheets, mattresses, dog baskets, whenever there is an infestation.
Mop floors with 2 Litres of warm water containing a teaspoon of peppermint, tea tree and eucalyptus oil.

Flies

The most important method is to prevent flies from breeding. They lay their eggs in decomposing organic matter, always cover up food scraps in the kitchen. Use screens on windows and doors. Invest in a fly swat.
To repel grow basil in pots where flies are a nuisance or place fresh cut basil in vases and place where needed.
Burn eucalyptus leaves on the BBQ to repel flies and mosquitoes.

Mosquitoes

Use nets and flyscreens, clean up any water lying around, and then look at repellents. Only female mosquitoes bite, they breed in any small puddle of water and are most active at dusk and night.
To repel 5 drops of eucalyptus oil mixed with 40 mls of water in an oil burner. Eucalyptus oil burns like kerosene so try the oil alone in flares and lanterns.
Mosquitoes hate lavender. Hang small bunches of lavender outside doors, it lasts for months, plant lavender near and around verandas and BBQ area to keep mosquitoes from biting.
Grow basil in pots and place around the house to repel.
Rub crushed pennyroyal leaves on skin.
Rub the leaves or flowers of lavender on your skin to repel mosquitoes or make a mild lavender oil and rub on skin. To make the lavender oil place 10 drops of pure lavender oil with 50 ml of a plain oil such as almond, light olive oil or sunflower, alternatively cover a handful of lavender flowers with plain oil in a jar, and stand in the sun for a few weeks (shake occasionally) then strain and use.

Moths

Lavender flowers have been used for centuries to repel moths from clothes, dry the flowers and place in small bags amongst clothes, effective for 6 – 12 months.

Silverfish

To repel wipe the insides of drawers and cupboards with pure eucalyptus oil. Place cotton balls with 2 drops of eucalyptus oil on them in amongst linen, clothes and books, or where needed.
Silverfish commonly found in the house feed on paper and glue,. See cockroach controls as they also work for silverfish.
Fresh bay leaves in books will protect them from silverfish

Spiders

Spiders are natural predators of silverfish, flies, mosquitos, moths and many other common household pests BUT if you must have them removed from your house you can try repelling them using a spray that you apply to their favourite web building sites (usually corners of rooms and furniture legs).
Spider repellent spray, mix together 200mls of water, 10 mls of alcohol (gin or vodka), 5 drops of eucalyptus oil and 5 drops of lavender oil, shake well and spray (note this will not kill the spiders, just repel them).

Weevils

Fresh bay leaves placed into containers of flour and grains will repel weevils.
Freeze bags of grains and pasta for 24 hours to kill eggs before placing in containers in the cupboard.

NOTE
Developed by the Waste Planning and Education section of Lake Macquarie City Council. There has been little to no scientific testing on listed hints. Most methods are ‘old time’ favourites, traditionally used by our great grandparents. They are offered in good faith but the author makes no guarantees, and takes no responsibility for, the effectiveness or results of these suggestions. All chemicals, even natural ones, need to be used with care, always use personal protective equipment when using chemicals and store out of reach of children.

Further Info

ABC Online: www.abc.net.au ABC North Coast NSW
Sustainable Gardening Australia: www.sgaonline.org.au
Organic Gardening: www.organicgardening.com
Hunter Organic Growers Society Inc, PO Box 822, Hamilton NSW 2303

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