Got 22 points! I'm not sure if there's a way to get more than that since there only looked to be 3 wells which each gave 6 buckets of water.
I have the same complaints as some of the other comments here. The menuing to give the water to the plants is rather cumbersome and could be achieved with much fewer clicks. I was also kind of confused when I started what I was actually supposed to do. Perhaps having the buttons to spray the plants grayed out until they have water in their box would help. I did a round mostly just clicking those buttons and seeing nothing happen because I didn't know about the wells yet.