Neat little game. I loved the experimental nature of what you did. Some sort of in-game instruction or goal wouldn't be missed here. It took me a while to figure out what I was supposed to be doing. I'm not sure if there is a "lose" state to the game, but I couldn't find it. Even when I made my ants stay away from the toxic waste it felt like the plants were growing faster than the waste was killing them. The controls could be better, would love to be able to use WASD or arrow keys instead of NWES or click with the mouse, or even better if I could select my ants individually and tell them where to move like in an RTS-style game. Oh and some music would be nice, but I'm not sure how that would affect the voice recognition, so may not be feasible.
I loved the graphics, very good use of the limited pastel colors! Would like to see you do more with this concept. An ant kingdom strategy game would be awesome.
ETA: Sorry my mistake, looks like my computer speaker died, your audio is good :)