I think you are fussing over it a bit too much. I have some columbine grown from seed that I basically ignore and after a few years, I now have dozens of plants. If you cut off all the dead heads, it will not self seed, as it does quite well. Also, potting soil will not help much in the garden, it's meant for pots. If your roses nearby are doing well, I'd think the columbine will too. Many plants get yucky leaves after awhile, especially when it gets hot. The only thing I would say that it might be too much sun for columbine. I have mine in a shady spot because our sun down here is very strong.

I've decided just to take a step back and take your advice; leave it alone. I didn't understand that this is a self-seeding plant, I thought it came back from root stock. I have some four'oclocks that I grew from seed and I just let them be, they reseed and come back every year so I think I understand the concept now LOL.

Might columbine be like bleeding heart in that it grows and blooms only in the spring and then dies back after setting seed before the heat of summer?
Save your off-brand miracle gro feedings for your repeat blooming annuals like petunias,zinnias,marigolds etc.

No, columbine is not a biennial nor an ephemeral...it is a shade perennial. It may be a variety that has light green almost golden leaves. Some have blue green leaves and some are speckled. When they get leaf miner, cut those leaves off and destroy. It should put out nice new leaves. The foliage is almost prettier that the flowers.