Springtime is for lovers, and it’s no coincidence that springtime is when most love affairs with the region begin. Unless you have severe pollen allergies—not a trivial concern given the literal explosion of plant life at this time—you should try to experience this area at its peak of natural beauty during the magical period from mid-March to mid-May. Not surprisingly, lodging is the most expensive and most difficult to secure at that time.
The hardest time to get a room in Charleston [1] is during Spoleto [2] from Memorial Day through mid-June. Hilton Head’s busiest time is during the Verizon Heritage golf tournament in mid-April. Savannah [3]’s tricky time of year is the St. Patrick’s Day [4] celebration, a multiday event clustering around March 17. While last-minute cancellations are always possible, the only real guarantee is to secure reservations as far in advance as possible (a full year in advance is not unusual for these peak times).
Activity here slows down noticeably in July and August. But overall, summertime in the South gets a bad rap, and is often not appreciably worse than summers north of the Mason–Dixon Line.
My favorite time of year on the southeastern coast is the middle of November, when the tourist crush noticeably subsides with the onset of the holidays. Not only are the days delightful and the nights crisp (but not frigid), but you can get a room at a good price.
Links:
[1] http://www.moon.com/destinations/charleston-savannah/charleston
[2] http://www.moon.com/destinations/charleston-savannah/charleston/entertainment/festivals/may
[3] http://www.moon.com/destinations/charleston-savannah/savannah
[4] http://www.moon.com/destinations/charleston-savannah/savannah/entertainment/festivals/march