The 1-drops and Shrubadier should be your main mulligan targets. Landscaping is also a good keep, whereas you should only keep Dendrologist if you have a way to push out a Treant early on.

The deck should be played like any Token Druid ever: get stuff out, buff them, and make favorable trades until you feel like you can start pushing for lethal in 1-3 turns (this usually means having Savage Roar in hand).