You'll need to grow some willow trees to clear the goal, but afterwards to get the drops you can swap to the other items. From what I've read so far, drops are really random and inconsistent. It will probably depend on what you have most of... 800 coins for the new 3x trees which you can chop immediately, or 300 coins for the willow and then energy to chop. Just remember we are in this for the long haul!