jump directly to content.
Principles. Crops. Pests. Control methods Library. Links.
key visual: online information service for Non-chemical Pest Management in the Tropics


Scientific name: Allium sativum
Family: Alliaceae

picture discription
Photo by Jewel Kinilitan-Bissdorf

Plant parts used

Whole plant, bulbs, leaves, flower (Prakash; Rao, 1997: pp.15-16)

Mode of action

Repellent, insecticidal, nematicidal, fungicidal, antibiotic (Prakash; Rao, 1997: pp.15-16)


Materials Methods of preparation How to use Target pests
Garlic bulb extract
(Vijayalakshmi; et.al, 1999: pp. 1-23)

85 grams of chopped garlic
50 ml of mineral oil
(kerosene or vegetable oil)
10 ml of soap
950 ml of water
Bottle container

Add garlic to vegetable oil.
Allow mixture to stand for 24 hours.
Add water and stir in the soap.
Store in bottle container.

Dilute 1 part of the emulsion
with 19 parts of water (for example, 50 ml of
emulsion to 950 ml of water).
Shake well before spraying.
Spray thoroughly on the infested plant,
preferably early in the morning.

American bollworm Armyworm
Cotton stainer
Onion thrips
Potato tuber moth
Root knot nematode
Sugarcane shoot borer
Bacterial diseases
Downy mildew
Rice blast
Garlic bulb extract
(Brooklyn Botanic Garden, 2000: p. 98)

2 garlic bulbs
Few drops of soap
4 cups of water
Bottle container

Grind garlic.
Allow mixture to stand for 24 hours.
Add water and stir in the soap.
Store in bottle container.
Strain before using.

Dilute 1 part of the emulsion
with 9 parts of water.
Shake well before spraying.
Spray thoroughly on the infested plant,
preferably early in the morning.

Black spots
Fruit rots
Garlic oil spray
(Ellis; Bradley, 1996: p. 473)

100 grams of garlic
2 tbsp of mineral oil
10.5 liters of water
10 ml of soap
Covered container

Chop garlic finely.
Soak garlic in mineral oil for a day.
Add œ liter of water and soap.
Blend well by stirring thoroughly.

Dilute the filtrate with
10 liters of water.
Fill the sprayer.
Shake sprayer from time to
time to avoid oil from floating.
Spray on the infested plant thoroughly.

Imported cabbage worm
Squash bugs
Garlic oil emulsion
(Vijayalakshmi; et.al, 1999: pp. 1-23)

50 ml of garlic oil
950 ml of water
1 ml of soap

Add soap to oil.
Blend well by stirring thoroughly.
Add water.

To prevent oil from floating,
immediately spray extract on infested
plants and shake sprayer from time to time.
Spray early in the morning
or late afternoon.

American bollworm
Potato tuber moth
Rice blast
Rice brown leaf spot
Root knot nematode

Standard procedures for the preparation and application of the plant extracts

  1. Select plant parts that are free from diseases.
  2. When storing the plant parts for future usage, make sure that they are properly dried and are stored in an airy container (never use plastic container), away from direct sunlight and moisture. Make sure that they are free from molds before using them.
  3. Use utensils for the extract preparation that are not use for your food preparation and for drinking and cooking water containers. Clean properly all the utensils every time after using them.
  4. Do not have a direct contact with the crude extract while in the process of the preparation and during the application.
  5. Make sure that you place the plant extract out of reach of children and house pets while leaving it overnight.
  6. Harvest all the mature and ripe fruits before plant extract application.
  7. Always test the plant extract formulation on a few infested plants first before going into large scale spraying. When adding soap as an emulsifier, use a potash-based one.
  8. Wear protective clothing while applying the extract.
  9. Wash your hands after handling the plant extract.

Effect on humans

None known during the write-up, however take extra caution as extract maybe harmful to people with very sensitive skin.

Effect on non-target organisms

Garlic oil spray has a broad-spectrum effect. It is non-selective so it can kill beneficial insects as well. This is not recommended for aphid control since it kills the natural enemies of aphids. It should be limited to home and garden applications where natural controls are rarely present (Olkowski; Daar; Olkowski, 1995: pp. 92-93).

External links


 to the top        PAN Germany, OISAT; Email oisat@pan-germany.org