I may be the Queen of potted plants, but even I will eventually throw in the towel with pots. I'd had a Salvia mexicana 'Limelight' for several years in a pot. It just never did much.  I think one year I actually had one blossom. Before I threw it away, I decided to plant it in one of my lavender beds figuring it would die.  The plant took off growing and hasn't stopped.  With the blossoms,  it's over four feet tall. 

And what blossoms they are,  beautiful dark purple petals exploding from lime green calyces.  They are definitely eye-catchers. It's so nice to have them in the garden in the fall when many other plants have stopped blooming.
They take full sun and average to low water.  They are hardy to the mid twenties. Some plants just seem to do better in the ground.  So before you throw anything out , give it one last chance and plunk it in the ground.  It might surprise you.