I used to be into native plants and that's a big ask.

Assuming a USA buyer, you'd have to ask for their zip code, then match that to the plants, many of which would probably have to be individually coded & entered (the zip codes they are native to), a map blur across the US which would vary for each species.

The binary qualities (toxic/nontoxic) on the other hand seem easy to add.

For invasiveness: that may be a reason why not too many "Amazon for plants" websites exist. But a simple binary "flagged as invasive", like a red dot on its product page, would be a terrific addition.