Well, unfortunately all perennials do not bloom at the same time in each zone, so you are asking for almost the impossible. For example, poppies are a summer treat in most zones. They are spring flowers here!

A great resource is to get the book "Gardening Round Atlanta". The last chapter has a beautiful essay made from a garden journal. Although it is one year in the garden, the writer does write about bloom time in previous years and what has affected bloom time. Very good read. The charts in the book do list some bloom times but are limited in their scope of plant varieties. Still a good place to start.
Begin a garden journal.

GGG

I was looking for the same kind of information a few years ago . The closest thing I found was the UGA garden trail results. It doesn't list anything by bloom time, but for every plant they list the date of the first bloom and the length of bloom. Other than that, I rely on what I see blooming and past experience with my own plants. I'm real good at recording what's in and out of bloom at the beginning and end of the season. I'm real bad about doing it the rest of the time - probably because I don't have anything blooming in the middle of the season.

Here is a link that might be useful: UGA Garden Trials

Of course you can just keep an eye on your neighbors gardens, but even then it's hard to tell. My passionflower vine hasn't even started blooming yet, for instance, but I know other peoples have been in bloom for weeks already. And our lantanas are all in serious bloom already but I'm pretty sure that some years it's taken them til mid-June to start.

Hi, mud. The Georgia Native Plant Society offers a bloom chart for native perennials on their web site. Elizabeth Lawrence's books are available in reprint paperbacks, and she discusses many many plants in a chronological format in them. Although all her books are classics, she charted bloom times for her Piedmont area over years and gathered together the data in an index in her 'In a Southern Garden.'

I forgot, the Georgia Perennial Plant Association also has a bloom time chart on their web site, for perennials, of course, but also a few shrubs and vines.

I found it! The American Horticultural Society publishes a book titled "Plants for Every Season". It divides blooming times into Early Spring, Late Spring, Early Summer, Late Summer, Autumn, Winter and All Season. Plants within these catagories are broken out by color. I bought a used copy so I can fill in empty pockets throughout the seasons.

GAmud