Ripening Tomatoes

3.0 based on 11 ratings

Updated on Oct 14, 2013

Grade Level: 6th - 8th; Type: Botany


In this science project, you will examine how to stop the ripening process of a tomato, as well as the effect that this has on the plant’s reproductive capabilities.

Research Questions:

  • What stops a tomato from ripening?
  • Does killing the ethylene in a tomato stop the tomato from reproducing?

Did you know that an enzyme called ethylene causes a tomato to ripen? If you kill the ethylene in a tomato, the ripening process will stop. This science project lets you take a look at how this works. It also lets you explore whether the ripening process and the reproduction of a tomato are related.


  • Permanent marker
  • Tomato plant with at least ten green, fully-grown tomatoes
  • Brick or cinder block
  • Pot
  • Tap water
  • 2 paper towels
  • 2 glass jars

Experimental Procedure

  1. Write the letter “C” for “Control” in permanent marker on five green, but fully-grown tomatoes.
  2. Write the letter “E” for “Experimental” on five other green, but fully-grown tomatoes.
  3. Position a brick or cinder block near the tomato plant.
  4. Fill the pot about halfway with very hot tap water.
  5. Carry the pot near the plant and place it on the brick. Lower one of the “E” tomatoes into the pot and leave it there for five minutes.
  6. Repeat with each of the other “E” tomatoes.
  7. Observe the tomatoes over the next several weeks. How many of the control tomatoes ripen? How many of the experimental tomatoes?
  8. Moisten two paper towels, and use each one to line a glass jar.
  9. Cut each tomato open and remove the seeds. Place 20 seeds from the “E” tomatoes into one jar between the paper towel and the glass sides, and 20 seeds from the “C” tomatoes into the second jar. Label the jars accordingly.
  10. Leave the jars in a sunny area for a few days. How many seeds sprout from each jar?

Terms/Concepts: Enzyme; Ethylene; What makes a tomato ripen?; How does a tomato reproduce?


  • Experiments You Can Do in Your Backyard, edited by Joanna Callihan and Nathan Hemmelgarn. Pp 70-71.
Keren Perles has worked as an educational writer, editor, teacher, and tutor of all ages. Her experience spans the subject areas, from science and math, to English and the Hebrew language.

How likely are you to recommend to your friends and colleagues?

Not at all likely
Extremely likely