A very simple action, beside harvest, is multi harvest.
You click it, then when you click and drag on the ground, a highlighted area appears, when you release the mouse button, your character automatically harvests all crops in the box.
Another one, it multi plant, which is the same only instead of harvesting, it plants whatever seeds are inventory in the highlighted box until you run out of seeds or it has planted in all plantable tiles.
VERY useful.