Subject: questions about my tropism experiment

For My science fair i am doing a project on tropism.  I have read about 
experiments where a bean plant grows through a maze. My Plan is to create 
several models of a small maze with 2 routes to light, one distinctly 
shorter than the other. I plan on seeing if the plant goes the fastest 
route and how often. I would compare a couple diffrent factors, i have 
been thinking about small amounts of caffeine, or hormone treatment.  i 
would need to do many tests, so i am worried that i would not be able to 
complete my experiment in just over 2 months. Are there any faster growing 
vine plants that i could use? do you have any suggestions to make my 
experiment better?Thank you very much for your time. -Jake-

Re: questions about my tropism experiment