Hi there. I am very new to the concept of identifying plants using their latin or botanical names. I've just started to learn about this and decided to begin properly identifying the genus and species of many of the plants I grow so that I understand what the heck other gardeners are talking about.

Anyway, 'May Night' Salvia has confused me. I understand it's a hybrid but I have seen three different labels for this on various websites:

Salvia x superba 'May Night'

Salvia x sylvestris 'May Night'

Salvia nemerosa 'May Night'

Can someone please explain to me what this means? Which is correct? Are they all correct? Help.

Sincerely, Squirrellypete