I've had mine for over a decade and a half at this point. "Botanical" is pretty self explanatory, I enjoy botany and have always been the one people ask for identification or care tips for random flora. I also used to take care of a garden and many houseplants but that hasn't happened for quite some time. Plus it helps that I enjoy green as my favorite color :]
The "Canopus" part is a bit more lore heavy. Obviously, like many people I love learning about the universe. One of the things I learned early on (since I specifically liked learning constellations and their lore) is that Canopus is the second brightest star in the sky. I thought this was pretty apt for me because if I ever hold any responsibility/power I'd rather it be as second in command rather than the main person in charge. It is also part of a larger constellation for the Argo Navis constellation acting as the steering oar/stern which guides direction. Canopus is also said to be named after the pilot of a ship of a Spartan king. I've often been the one to give advice/help others with events in their life (mentally, emotionally, physically, & financially) so a guiding star was right up my alley.
So acting as some botanical wisdom and guidance, botanicalCanopus was born. That and since I go by Sage, botanical wisdom is almost a ironic.