I have been so pleased with this Salvia! It has more than tripled in width and height and is a relentless bloomer- beautiful blue blooms almost the same as "Black and Blue" blooms. I love that it spreads by runners. I really want to get the var purpurea (purple flowers) as well as "Argentine Skies" with its beautiful pale blue/lavender blooms. I haven't been on this site for a few weeks as I have been working on soil prep for flower beds (especially to add more Agastaches) and for grass seed as well. I still have more to do and need to get my grass seed in soon but I have sure missed keeping up with this forum especially and the whole site. This picture of the blooms on my S Guaranitica is one I have taken with my new iPhone which has a much better camera.

Beautiful.
Is it this one? Salvia guaranitica is a synonym.
Blue Anise Sage (Salvia coerulea Nectar Blue™)

Please, does it only spread by runners? or does it also make seeds?

Did you mean salvia guanajuato?

@duane456 No it is S Guaranitica. @greene you are partially correct It is known as Blue Anise sage and Salvia Coerulea but it is not "Black and Bloom"- the calyces of mine are green. Interestingly in the database it gives it hardiness to zone 8 but I have seen other sources say zone 7. The small online nursery where I got mine has had it in her zone 6 garden for years and it has survived the winters. I am hoping mine does as well. Duane, maybe that is why the name was confusing. Greene your question is very timely!! I just yesterday collected a few seeds from it! I have sown them in a small container with potting mix so will see what happens. I do not have a lot of experience with seeds and cuttings but it has been fun learning. I will definitely post an update if the seeds grow.

jg0613 said:...The small online nursery where I got mine has had it in her zone 6 garden for years and it has survived the winters...

If you would like to share the name of the online nursery you can add them to The Green Pages; look over on the left of the screen.

Thanks @greene I will do that. I ordered multiple plants from her this year and was very pleased with all of them. I am on my phone now so this site is set up a little differently than on the computer. It is Gardens in the Wood of Grassy Creek in NC.

Accepted names are constantly changing.
S. guaranitica is listed as a synonym for this one in our database:
(Salvia coerulea 'Blue Ensign') in the Salvias Database and it has a green calyx.