Tips and cheats

Can anyone help with tips and tricks for this game. I know when you use the water upgrade, it produces more plants. Anything else that might help would be greatly appreciated.

If you give up on a level just play game but do not make the last thing to sell for 1 hour
the timmer resets to 00:00 I normaly have the thing made and just sitting to go to Joy to sell by 55:00 then after 59:55 I move that thing to Joy to sell and get GOLD (I know its a Bad Cheat but after 15 trys on a level I gave up and just to see how many things I Can Buy and how long I could play found this cheat.