It's an interesting thing.
I've read for years that coffee grinds are good for plants, and that McDonald's even donates their old coffee grinds (at least, before the pandemic) for fertilizing gardens.
And then... I found an article stating that the very reason the plants that produce caffeine are doing so is because it's a natural toxin that kills off the competing vegetation around them. Coffee grounds still contain caffeine after being used and are also highly acidic, which is deadly for some species, so using coffee grinds will actually kill off some varieties of plants.
Similar thing with tonic water (ask me how I know.)
I had some neighbors who were just renting the house down the street for a few days, and when they left, they gave me some kitchen items they hadn't used up, including a couple sealed bottles of tonic water.
I'm not a drinker and didn't want to waste it, so good old Google had said that tonic water was "good for plants." Sure it is.
My plants started to wilt within just an hour or two of using it.
Fortunately I noticed right away and was able to save them by thoroughly flushing out the soil.
As much as I'd love to use "natural" fertilizers, so far I've stuck to diluted Miracle Gro (I dilute it just a tad more than recommended to avoid burning the plants with too much of a supposed good thing,) and for my little indoor "garden", that seems to work best for now.