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June 06, 2012

How to make garlic spray for plants as organic garden pest control

Uses & Benefits of using garlic spray in a tropical organic garden:
  • natural anti-fungal agent
  • Natural Pesticide
  • Natural anti-bacterial agent


kang kong

White flies on my kang kong leaves

Watermelon. Note the brown leaf in the top right.

To make garlic spray for the garden, you will need:
  • 3-4 cloves garlic
  • 1 tbsp mineral oil
  • 1 pint water
  • 1 tsp liquid soap such as dishwashing liquid (to break down bodies of aphids and other soft bodied garden pests. Bleach free)
  • Blender
  • A strainer
  • Storage container with a secure lid
  • A spray bottle

Instructions for making garlic spray for an organic garden
  1. Mince garlic
  2. Combine garlic with oil
  3. Allow the garlic and oil mixture to stand for 24 hours before straining. (I usually throw away the pith. BTW, oils are unsuitable for the composting process).
  4. Add water and soap
  5. Store
  6. To use, shake well and combine 2 tbsp of the mixture with 1 pint of water. Spray over the foliage. Whenever possible, apply on the underside of leaves to extend the period during which the spray remains on the leaves in spite of rain.

  • Organic garden garlic spray is a non selective insecticide.
  • Did you know that aliums are not good for dogs? Garlic may be toxic for dogs if eaten. (Onions is more toxic and has been related to dog fatality). Although garlic spray is not eaten by dogs, I worry that it may still be absorbed by dogs and would therefore be careful when / if dogs are around. 

Observations and noteworthy points
  • My aubergine (aka eggplant) plants were transformed overnight. Literally! The plants became very healthy and highly productive after using garlic spray. I saw a similar transformation with my dwarf lime tree.
  • Spraying on the underside of pepper leaves has made a huge transformation to their health and survivability in my personal experience. I do not see all of the horrible white and black mass building up on the underside of the leaves when I keep on top of the spraying. 
  • The most drastic distress signs in my garden may be with the cucurbits (zucchinis, cucumbers, pumpkins, watermelons and so on). The otherwise green leaves turned white, ashy or brown and looked like brittle paper. As for fruit production, apart from being fewer, the fruits were oddly shaped. I found that using garlic spray (along with pepper spray for voracious caterpillars and baking soda spray) was the only way that I could extend the life of these plants. Unfortunately, unlike the other plants, I need to keep on top of spraying just to keep the cucurbits alive. So I have lost these plants.
  • Tomato plants responded well but not as drastically as did the aubergine / eggplant plants or lime tree.
  • I have also used garlic spray on kang kong with good results.

Just on a pretty note, I have planted marigolds in my garden. Apart from their beauty, their strong scent is also a form of natural pest control. I do not think that I have enough of these wonderful plants in my garden currently.

Marigolds can be used as natural pest control by organic gardeners. I love how beautiful they are.
Marigolds are a natural form of pest control for a tropical organic garden

Other homemade sprays for organic gardens
  • Pepper spray for the garden
  • Baking soda spray for plants
  • Epsom salt spray for plants


  1. I think organic pest control was more effective and its easy to used .. And free from hazardous chemicals..

    st george pest control

  2. can this be used for every melon types

    1. Yes, this spray will help with aphids and other common pests. However, regarding cucumbers and melon types, this spray has not been able to get rid of the problem where the leaves turn dry and brown. (I don't remember the name of that). If you know what the other problem is, please enlighten me.

    2. AnonymousJuly 29, 2013

      That problem with the melon, cucumber and zuchhinni leaves drying out and turning brown is not a fungal problem. It is a kind of pest that burrows through the inside of the plant.

    3. Regarding the pest that burrows through the inside of the melon, cukes and zuchinni leaves, will neem spray help? I'm now making my own neem spray for the garden and, if there is hope of keeping those plants alive, I'll have another go at growing them.

    4. Here are some herbs that are supposed to help repel pesky insects:
      Wormwood, southernwood = repels moths, slugs and flies
      Rue= repels Japanese beetles, controls fleas and repels cats
      Feverfew, Tansy, Pyrethrum = repels moths, flies, ants, mice cockroaches and more
      Lavender = repels flies, silverfish and fleas
      Sage = repels a large variety of insect
      Basil= repels flies and mosquitos and tomato worm
      Lemongrass = repels mosquitos
      growing garlic = repels Aphids, Japanese beetles and much much more
      Thyme = cabbage worm
      Borage= very pretty(tastes a little like cucumber and all is edible) Plant near tomatoes, strawberries and squash

      All these are edible herbs that also serve as insect repellents.

      I also use the Blood flower as a Trap plant for aphids...I plant it away from my food garden. It attracts aphids(bad) then it attracts the caterpillars who eat the aphids and the plant leaves. These caterpillars turn into butterflies. Hang upside-down and make the cocoon on the underside of leaves. The aphids also attract lots of ladybugs(good). The plant attracts bees, butterflies and hummingbirds.

    5. Brilliant! Thanks JA. Your list is very helpful. Have a wonderful day!

  3. Organic pest control methods are 100 % natural and pose no threat to your health or the environment. Your post is really superb!!!. Thanks shared the best information because I and my friends have impressed a lot, great work!

  4. AnonymousJuly 04, 2015

    dont like the mineral oil as is toxic other oils effective?

    1. AnonymousJuly 05, 2015

      Which oil do you recommend please?