There’s a long history to using the natural plants and fungi around us to treat wounds, illness, poisons, and even cause various other effects. So much so, that I honestly kind of regret the whole “cure disease” spells or cure-all medicines common in fantasy and scifi rpgs.
Sure, it simplifies things, but I honestly think it kind of misses a huge opportunity for immersion, where the very setting itself plays more of a role other than that of combat.
Heck, even leaving diseases aside, plants are basically the proto-pill, drugs growing out of the dirt with all sorts of unexpected uses or effects just waiting to be discovered or learned. You could probably replace a lot of spells or scifi-nano-shots or serums with a simple extremely rare but highly useful plant. The rarity lets you set the price, so running into a meadow or forest of the plant can feel like a goldmine, while the difficulty in keeping said plants alive or harvesting the drug from them in the first place can act as a control on abuse or a creative puzzle for the players to engage with!
After all, if there’s tons of magical/fantastic or otherwise unusual alien beasts around, makes sense that there’d be magical/fantastic or otherwise unusual alien plants around, too. “Medicinal plant tea which grants increased strength for X time after drinking” makes for a simple but interesting twist on the whole “Potion of Giant Strength” bit, and makes it seem like something the players themselves could actually learn the secrets of if you’re willing to let them and they put in the work.
So to help get the creative juices flowing, I thought I’d make up a little rough table of different ways to use different plants. Roll for each column separately:
|Using Medicinal Herbs|
|2||Seeds or pollon||Burned||Skin/wound contact|
|4||Petals or Leaves||Ground|
|5||Fruit or Berry||Soaked||Eaten|
|7||Stem or Branch||Mixed (roll for plant twice, both required)|
|8||Bud||GM’s choice (make it unique!)||Chewed|
Granted, this isn’t very detailed, but I figure it’s a good starting point. For the different effects, well, you could make up a list of your own and then roll for those, or put together the different spells you think would be suited to a herbal origin. (along with various poisons so the players don’t go snorting half the countryside)
And it gets even better when you consider other ways it might replace the typical uses of magic in a setting. Those old hedge wizard studies become suddenly easier to picture, you can almost smell the heavy scent of fifty different plants, and preparations. Books of lost lore could describe the mythical uses and ways of preparing unusual or long-forgotten plants, and maybe even where to find them!
Don’t forget, the secret of immortality that Gilgamesh sought was a plant that grew at the bottom of an impassable river. How’s that for a quest item? (Just make sure you don’t let a snake eat it instead while you’re napping)