Science project

Do Insecticides Stunt Plant Growth?

Research Questions:

Are insecticides harmful to humans?

Plants grow through a process called photosynthesis. This requires sunlight to take place. The chlorophyll located in the chloroplast of the plant cells grabs sunlight and starts the reactions that are needed to make the plant grow. Water is also needed in the growth equation because, like humans and animals, plants need moisture to quench their thirst.

Insecticides repel bugs. Bugs are not a good thing for plants (except for pollinating insects) as some of these insects create holes and contaminate the plants.


  • Any insecticide (don't need a huge bottle)
  • Bean seeds
  • Soil on the ground
  • Water
  • Sunlight

Experimental Procedure:

  1. Plant 2 groups of seeds at a distance from each other in an outside yard. Make sure they will get the same amount of sunlight.
  2. Spray some insecticide on one group of seeds. Be sure to remember which one gets the insecticide.
  3. Observe the germination rate and growth of both of the seed groups.
  4. Every few days, spray the designated plant with insecticide.
  5. Record any difference you see in overall plant health and growth for several weeks, up to one month.

Suggested Chart


Day 1
Day 2
Day 3
Day 4
Day 5
Day 6
Day 7
With Insecticide








No Insecticide









Terms/Concepts: Insecticide; Plant Growth; Photosynthesis


Greene, Stanley A.; Pohanish, Richard P. (editors) (2005). Sittig's Handbook of Pesticides and Agricultural Chemicals. SciTech Publishing, Inc. ISBN 0-8155-1516-2.

Disclaimer and Safety Precautions provides the Science Fair Project Ideas for informational purposes only. does not make any guarantee or representation regarding the Science Fair Project Ideas and is not responsible or liable for any loss or damage, directly or indirectly, caused by your use of such information. By accessing the Science Fair Project Ideas, you waive and renounce any claims against that arise thereof. In addition, your access to's website and Science Fair Project Ideas is covered by's Privacy Policy and site Terms of Use, which include limitations on's liability.

Warning is hereby given that not all Project Ideas are appropriate for all individuals or in all circumstances. Implementation of any Science Project Idea should be undertaken only in appropriate settings and with appropriate parental or other supervision. Reading and following the safety precautions of all materials used in a project is the sole responsibility of each individual. For further information, consult your state's handbook of Science Safety.

Add to collection

Create new collection

Create new collection

New Collection


New Collection>

0 items