Natural pesticides and antsFeatured science projectScience project video

popular science fair projects
Complexity level:
Project cost ($):
Time required:
1 day to prepare, 1 hour for the science project experiment
Material availability:
Easily found.
Safety concerns:

Handle ants carefully. They bite! Adult supervision or assistance required


This science fair project was conducted to find out the effectiveness of using natural pesticides to control ants around the house. The science fair project was done using lemon juice, apple juice, tomato juice and carrot juice.


Lemon juice is more effective as a pesticide, than apple, tomato or carrot juice, against ants.


Natural pesticides

Pesticides are substances used to kill or to keep insects and pests at bay, away from our homes, gardens and farms. These insects are a nuisance as they damage property and cause diseases. These pests are also unhygienic. Most commercially available pesticides contain chemicals that are harmful to our health. When we empty a can of insecticide spray, some of these fumes are inevitably inhaled and enter our lungs. The pesticide used by farmers also seep into the soil and contaminate our food chain and drinking water.

An alternative to using chemical pesticides is natural pesticides. These are naturally produced substances in plants. These natural pesticides are usually very safe for use and cause no harrm to the environment. However not all natural pesticides are completely safe. Nicotine which is derived from tobacco is very addictive and to some extent, even more toxic than many chemical pesticides.

Examples of natural pesticides are lemon juice, bay leaves or cucumber peel. Borax, a salt crystal, can be used in powder form to keep termites and cockroaches away. Honey can be used to attract flies and trap flies – once they flies land on the honey, the honey sticks to their feet and prevents them from escaping.

Scientific Terms

Natural pesticides, chemical pesticides, nicotine, toxic


The materials required for this science fair project:
- 1 empty bottle
- black ants (collected from an ant hill)
- 1 pair of gloves
- 1 lemon
- 1 apple
- 1 tomato
- 1 carrot
- 4 plastic cups
- 1 juice extractor


1. For this science fair project, the independent variable is the type of juice used – lemon, apple, tomato and carrot. The dependent variable is the movement of  ants - in and out of the circle. This is determined by observing if the ants cross the line made  from the juice. The constants (control variables) are the type of ants used, the size of the circle, the concentration of the juice and the width of the line.

2. A small ant hill is located. Wearing   latex gloves,   collect as many ants as possible  in  an  empty bottle. Be extremely careful to avoid being bitten. Do not let the ants crawl over unprotected bare skin. Adult assistance is required.

3. Once you have collected the ants, close the cover and put the bottle aside.

4. Using the juice extractor, prepare  lemon, apple, tomato and carrot juice and pour them into  4 cups.

5. Draw  four  circles on the floor or table using the  extracted juices. Ensure that the lines are thick, and wet with juice. Open the bottle containing the ants and release some of the ants into each of the circles.

6. Observe if the ants are able to cross the lines drawn, and  exit the circle. Record the observations in the table below.


It  was observed that lemon juice was effective in keeping the ants within the circle. The apple juice, tomato and carrot juices were not effective.

Natural pesticide

Lemon juice

Apple juice

Tomato juice

Carrot juice






Y - the ants did not exit the circle

X – the ants escaped from the circle


Out hypothesis that lemon juice is more effective as a pesticide, than apple, tomato or carrot juice, against ants, has been proven to be correct.

Using natural pesticides derived from plants, vegetables or fruits are a better and safer way of keeping insects at bay. Their effectiveness may be for a short period of time and they be a more expensive means of pest control, but they are safer and more environmentally. Regular use of chemical pesticides can be harmful to our health, especially to our children. These insecticides can enter our bodies through inhalation of fumes or the contamination of food and drinking water, causing various types of illnesses.

Also consider

Would your observations be different if this science fair project were to be repeated using different types of insects like cockroaches or termites?

The science project experiment can also be repeated using different types of natural substances like vinegar, saltwater, garlic oil or tea.


Natural pesticide alternatives -

Natural pesticides -

How to kill ant with natural pesticides -