Instructions
Visit Kross' Architectural Services shop. Ask Kross to build a barn for you. Barns cost 1,000 gold. You also need 100 pieces of lumber. Find lumber in the forest when you cut down trees.
Go to Erik's Seed Shop. Purchase as many fodder seeds as you want for 30 gold each.
Plant one fodder seed per square in your garden. In a few days, the grass grows very tall.
Equip your scythe and select the fodder to cut it down. The fodder is automatically transported into the barn.
Use the fodder by selecting it in the barn's storage compartment. Carry the fodder to the monster you want to feed and place it in its trough.
Water the bare patch where you cut the fodder down. More fodder will grow in a few days.