Hi Don!
to ATP!
I hope you visit our Agastache and Salvias forum also!
http://garden.org/forums/view/...
I'm in zone 6a also, living and gardening in northern KY. I grow a lot of annual 'not hardy' Salvias for 6a. I plant them into containers (16 inch and larger).
As with all Salvias and annuals, deadheading them, keeping them fertilized and watering them. I use a time-release fertilizer (osmocote) at planting time unless it's already in the potting mix.
The splendens: bonfire, flare, hotline red, will sometimes produce less flowers for me as it gets to late Summer - early Fall when I grow them, but I still grow them.
I love and prefer to grow the coccinea varieties. They always do great here all Summer and season. I've grown the 'Lady in Red', 'Coral Nymph', 'Forest Fire' and I've grown the white one, 'Snow Nymph' before also.
Salvia 'Wendy's Wish' is one that stays flowering. Here's a pic I took a few days ago,
Salvia 'Wendy's Wish'
A pic that a member took in PA,
Salvia 'Amistad' is constantly in bloom all season. It was already blooming when I received it in the mail. Here's a pic I took last year. There are 3 plants in this 18 gallon tub,
Salvia 'Amistad'
Salvia 'Black and Blue' is a good one too.
Anise-Scented Sage (Salvia coerulea 'Black and Blue') Here's a few pics I took a few years ago,
I get the majority of my Salvias from Flowers By The Sea. They specialize in Salvias all year and are located in Elk, CA. They've an extensive selection of all kinds of Salvias.
http://www.fbts.com/ The owner, Kermit Carter is a member here and I'm going to ask
@FBTS if he could comment please and answer your question also to help you out.
He's very knowledgeable regarding Salvias.
Julia for bringing this to my attention.
Marilyn