I live in Atlanta, and despite living here for 15 years (and KNOWING
the last frost is always later than you think...), I planted hundreds
of petunia in my flower beds in nice, manure-rich beds, but didn't get
a chance to put mulch around them. That very night a cold front blew
through and temps dropped. It was above freezing most of the night, but
the temps were 30F for about 2 hours before sunrise.

When I awoke, the petunia looked fine--just a light layer of frost on
all of them. But when I got home that evening, all of the blooms had
wilted. I put mulch around them and pinched each of the wilted blooms
and hoped for the best.

It's now been 2 weeks of 60-75F temperatures, and the petunia still
haven't bloomed again. The leaves are a nice, deep green and the plants
themselves aren't wilted, but each little bud that appears turns brown
and shrivels before ever opening into a bloom.

Has the frost permanently damaged these plants? Do I need to rip them
out and start over? Or can I expect some blooms in a few weeks once the
plant has a chance to completely renew all of the buds?