Resources replenish based on their hourly production (minus troop upkeep for food).
You can increase your long term production of resources by developing (and/or upgrading) your fields, conquering appropriate wilderness spots (they DO stack), assigning a knight to be your steward (after building a Knight’s Hall) and completing appropriate research (after building an Alchemy Lab).
In the short term, you can increase production using items from you’re My Items tab (gained by completing quests or spending gems).
To reduce demand for food, you will need to get rid of troops (putting them in the wilds no longer works).