[omalley]

Use the wiper motor or maybe something smaller with a simple and short stroke. At the top of each stroke the mouth gets bumped open.
Have the plants speech on a cd and play continuously. Use amplified speakers to play the sound.
Use a switch or 110 v remote (Home Depot) and power the motor and the amplified speakers from this. Keep the cd player running constantly with a seperate power source so there is no "lag" time waiting for it to spin up.

I am all into cheap.

james

 

[omalley]

Reciprocating Motor Assembly-The Electronic Goldmine

Found this while surfing. Instead of the wiper motor. You may need to use a lower voltage to slow the RPMs.