|MadSci Network: Earth Sciences|
A very good question, Kevin!! I judge a science fairs and have seen projects along this line (sound, talking, music, and so forth) a number of times. The interesting thing is that some students show differences and some don't. The first thing I look at when I see a project like this is how the experiment was conducted. For instance, lets take two plants to do this experiment on. We will talk to one plant, but not to the other. So the "non-talked-to" plant (called the control group) does not hear us talking to the "talked-to" plant (called the experimental group) we put them in separate rooms. Just from what we have set up so far let me point out the mistakes. 1) You really need a number of plants in each group. This helps make up for the fact that one may simply not grow as well. 2) In order to see if talking is having an effect, we need to make sure that nothing else is changing the growth of the plant. No two windows or rooms will have exactly the same temperature and light. This is what we would call in science an "uncontrolled variable". If you decide to keep the plants in the same place and move the ones you talk to, you have to move all of them so they all have the same stresses. 3) In the world of plants, I have found that every type of plant acts differently. The temperature, light, and water one type likes will kill another. I imagine that if talking has an effect, it will be different on every plant. 4) In talking to a plant, you are paying more attention to that individual and are more likely to notice it is dry, needs a leaf removed, or needs fertilizer, thus changing the growing conditions. To answer your question, in my humble opinion, talking to plants does not improve their growth. However, I have not been able to find any reliable references about this subject. If someone showed me some good, strong results that talking to a plant effects it, I would believe it. Something else I just thought about. I remember seeing a paper on the effect of "brushing" on the growth of greenhouse tomatoes. The researchers found that taking a large foam board and lightly stroking it across the tops of the plants slightly improved growth rates. This makes me wonder if talking to the plant would be like the wind blowing. Does a light wind improve plant growth? I hope that helps! Eric Biddinger Youth Educator Purdue University
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