When you first harvest a plant, its species is unknown. Interact with items in your inventory to try to identify them or eat them immediately. The higher your herbalism skills, the more likely you are to identify plants. It goes without saying that eating something unidentified can be dangerous, but depending on how you play The Sims 4, it can also be hilarious.
Eating plants can make you feel positive as long as they're not poisonous, but the benefits of plants extend beyond your hunger meter. As your Sim's Herbalism skills grow, they will be able to process plants and brew potions for a variety of purposes. To brew, have your Sim interact with cooking equipment. You must use a grill on campground grounds, but you can use a stove at home or in your cabin.
Sims with level 1 Herbology can brew very basic remedies such as mothballs. At advanced levels, there are some very useful potions that can greatly help your Sims get through their daily lives. Even better, many of the materials are available for free, and once you find a plant, you can take it home to plant and create more.
When you select a brew, rather than pausing and seeing a full list of recipes (as it does when making a meal), the pie menu asks you which treat you'd like to make. Hovering your mouse briefly over a recipe will pop up its ingredients and what your Sim is carrying, even if the item can't be made yet.
Brewing a cure will boost your Sim's Herbalism, whether they're on vacation or not. You can also purchase Volumes 2 and 3 of the Herbalism Skill Book to maximize your skills when you get home. Only Volume 1 is available from the Ranger Station.
