Radishes are a colourful, crisp vegetable that are usually eaten raw, particularly in salads.They are a cool-season crop and are best when grown in the spring and autumn. Since radishes mature quickly -- some varieties mature in as little as three weeks -- they are ideal for science experiments.
Sarah Agee of Science Buddies details this experiment that studies the effect of heat on radish seeds. The experiment entails microwaving radish seeds in three groups for five, 10 and 15 seconds. Seeds are then placed in plastic bags with a few drops of water, sealed, and appropriately marked for future observation. Another set of seeds is baked in an oven at 120 degrees Celsius (250 Fahrenheit) for 10 minutes, placed in a plastic bag with a few drops of water, sealed and appropriately marked. Finally, a control group of seeds, not baked or microwaved, is placed in a plastic bag with a few drops of water, sealed and marked. After the seeds have sprouted progress and results are charted on a graph.
The Center for Biology Education provides a constructivist science experiment using radish seeds. Constructivist experiments involve students constructing their own experiments. This experiment requires that students investigate a particular factor, such as heat or cold, and its effect on radish seed germination. Students come up with their own hypotheses, conduct the experiments in groups, and use peer assessment to grade the experiments.
In this experiment from Leyden Science, the independent variable tested is how the amount of light affects the germination of radish seeds. Three groups of seeds are used: seeds placed in dark, seeds placed in light and seeds placed in both light and dark. Students develop a hypothesis that asks if the seeds germinate better in dark or light. Thirty radish seeds are placed in three petri dishes layered on the bottom with wet paper towels. One dish is placed in the light, one in the dark, and one in partial light. Water is added as needed. A chart is provided to track the results daily.
This experiment involves placing radish seeds in small cups of soil. Water is used to hydrate one plant. A mixture of one-third bleach and two-thirds water is used on the second plant. The final plant uses a mixture of one-third vinegar and two-thirds water. Cups with seeds are placed in a window sill for light exposure. Progress is charted for seven days. The purpose of the experiment is to observe how bleach and vinegar affect the pH balance of the soil and the germination of the radish seeds.