Plants in pots need to have their root and foliage area capacities in balance with each other. Also, temperature, light, and fertility have to be maintained in the right ratios to each other, given the state of growth of the plant.

With automatic watering, a loose soil mix is best. A peat-perlite mix with extra perlite is better. Osmocote slow-release fertilizer is useful for even fertilizing.
The Eurasian species for the most part are seasonal to the extreme, being tap-rooted plants that die all the way back to the ground and have a relatively short seasons.

The American sages are for the most part seasonal as well. Salvia miniata is as close to an everblooming hummingbird sage that I can think of. The guaraniticas and their hybrids bloom most of all the warm season and make good container plants. Others with long pot lives and bloom periods are the puberulas and involucratas. Microphyllas and their hybrids with greggii also have long bloom periods and work well in pots.

There are others that I will report on later.

In order to keep them blooming, they need to be kept as warm as possible during the season. Doing this will necessitate giving them a rest period at some time, though.

I'll have to try osmocote. This summer my attempts at salvia pot culture met with mixed results, mainly I think do to lack of food. The one exception of salvia leucantha which grew well all summer and bloomed beautifully this fall until Friday nights freeze. Salvia Raspberry Delight and Royal didn't fair as well. They did manage to bloom all summer but weren't nearly as vigorous as those planted in the ground. If osmocate will get me past the vigor problem, then that is what I'll do. Are you taking orders this fall?

I have had good luck with the Greggii Salvias in pots.
I have a purple one and 'Caviar' and they both do great. I need to remember not to overwater, though, because they don't bloom well with too much water.

I also have Hot Lips and Indigo Spires in pots. Indigo Spires is in a tall, narrow pot that stands about 4' tall, and it has done well. Indigo Spires loves water.

I have heard that Sierra San Antonio is great as it is only 2' tall. I just use standard potting mix.

S. greggii and S. chiapensis do great for me in pots. Especially S. chiapensis which blooms all season (which is literally all year here in my zone in southern CA), and I don't mean a repeat bloom, I mean a constant bloom. I've seen hummers on it. I have two in the ground beneath a deciduous tree where it gets watering from the lawn sprinklers (an ideal setting for this plant), and one in a pot on the front porch which gets the same amount of sun but less water since I tend to forget sometimes, but it is forgiving and springs right back. It has a nice graceful habit for a pot and beautiful magenta blooms.

Oh, I also grow S. elegans 'Honey Melon', a dwarf variety of S. elegans, in an pot and it is happy there.

Jen

I grow Coral Nymph in a pot - it blooms all summer, comes in the house in fall and blooms all winter. And yes, hummers love it.

What size of pots do you use to grow your salvia's? Does it matter if they are clay or plastic?

I have several salvias in pots right now that are doing great, I based the pot size on the mature plant size and have them on a drip irrigation system so they don't dry out due to my forgettfulness. Almost all of mine are in clay pots that I lightly spray with prune-n-seal on the insides to retard some but not all of the water loss the others are in whiskey barrels.

Here are some of my favorite combos:

S. Sinaloensis in 12"- 'bean pots'
S. Mexicana 'Compton's form'- 16" terra cotta
S. Regla 24" -terra cotta
S. involucrata 'Mulberry Jam'- 16" sandstone
S. madrensis -whisky barrel halves

I had overwintered my potted B&B successfully in my above freezing florida room. If I'm not mistaken, you were the one that said I should be able to do it. I was a little skeptical; since I'm lousy at overwintering anything in pots. But, thanks to your advice, I did it ;) I also overwintered my duranta!

I just purchased (a half hour ago!) 3 "Lady in Red" that I'll be putting in a windowbox, and attempt to overwinter next year...

The more I garden the more I am learning that when it comes to pot size the bigger the better as to not allow them to get pot bound and compacted. I have used from a good bulk soil to organic bagged soil. If it needs sand, limestone or rock I mix it in. Due to some hardpan, clay soil and those darn gophers I have quite a few Salvias in containers.
They are:
Chamaedryoides, involucrata, sinaloensis, waverly, pratensis, splendens, elegans, coccinea, regla, penstemoides, cacalifolia, glechomaefolia, yunnanensis, greggii, spathacea, tingitana, disermas, jurisicii, microphylla hot lips, discolor, sagitatta, chiapensis, buchananii,lyrata, urica, blephoraphylla, hians, roborworksi, farinacea, viridis, semiatrata and a few more can't think of now. Please excuse my spelling.