Re: does talking to your plant affect it's growth?

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