Use garlic to control crop pests



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Content: Use garlic (Allium sativum) for intercropping, or as a spray or powder to repel many crop pests.

Why buy chemical pesticides when you can grow natural pesticides in your own garden? Garlic has a strong odor that repels many different pests that attack your crop. You can intercrop garlic to prevent the pests from going near the main crop. Or apply garlic spray or dust to the plants. Garlic is effective against many different insects, soil animals, rodents, and even some plant diseases.


If you plant garlic with your crop, pests are less likely to attack your crop. Garlic’s strong odor discourages insects from coming close to the crop. Plant garlic about every 1 1/2 metres (4 – 5 feet) throughout the garden area. A border planted around your garden or field is a good idea. It will discourage insects and even some animals from eating your crop. For example, in parts of South Africa, farmers plant a border of garlic around their gardens to keep out moles. In Trinidad, garlic is planted as a border for sugar cane. Many people plant garlic around their fruit trees to repel boring insects. For the most effective results, the garlic should be planted before the crop is planted so that the pests are discouraged while the crop is being established.


Garlic can also be used in a spray against pests. Here’s a simple way to make garlic spray. Crush a large handful of garlic cloves. Add 1/2 litre (1/2 quart) of boiling water to the crushed garlic and leave to soak for a day. After one day, strain the mixture through a cloth or fine sieve. Next, add 4 litres (4 1/2 quarts) of soapy water. Spray the affected plants early in the morning. If the pest doesn’t go away, spray again in three days. The spray will be effective for about a week. After one week if you’re going to continue to use it, you should make a new mixture.

There are lots of variations of garlic spray that you can make. For example, add two or three peppers and/or a couple of onions to make the spray even more effective. Do some experiments with different ingredients and see what works best for you.


If you do not have a sprayer or prefer not to spray your plants, garlic can be applied as a powder. Dry the garlic cloves, then crush them. After the morning dew has dried, dust or brush the powder on the plants.

To keep out many pests in your stored grain, dry and crush garlic leaves. Add some ashes and scatter the mixture in your storage area.


Garlic has been reported to be effective against many crop pests including certain beetles, mites, thrips, aphids, whiteflies, moths, nematodes, armyworms, and borers.

Information sources

1. This script was researched and compiled by Mary Tiessen, Crop Science Department, University of Guelph, Canada.

Garlic – Other uses/supplement

1. In Oaxaca, Mexico, they have a problem with human parasites in their meat. These parasites do not like garlic. In Mexico, they chop (mince) the garlic into very small pieces and eat it raw before each meal. Dose 1/2 – 1 tsp children, 1 – 2 tsp. adult.

2. In Nepal, they rub garlic on their body to control ringworm.

3. In Nigeria and the Philippines, they use garlic as a mosquito control.

4. All over the world, people use garlic as an herb to add more flavour to their food.

Spray variation: 3 hot peppers, 3 large onions, 1 garlic bulb – blend these with 1 gallon of water

Variation – Phils. 3 – 4 gloves garlic, 2 handfuls marigold leaves, 2-3 onions, 2-3 small hot peppers. Cover with water and boil. Let cool and dilute with 4 to 5 times water (3 tbs. soap flakes: 1-gallon water),

Insects: aphids, mites, beetles, thrips, whiteflies, weevils, ticks, moths.

Soil animals: nematodes, armyworms, borers.

Bacteria: Xanthamonas sp., fungi

Dried and crushed garlic leaves – will repel pests for about 90 days