The Sap is Rising...When is Southern too Southern?

~~Okay, raise your hand if you don't know what I mean by "the sap is rising?" I used this term in chapter 1 of FRIENDLY FIRE and one critiquer noted it with the question, "What sap?" I was describing the time in spring when the trees begin to leaf, bud, and bloom and a young bird's, cat's, hawk's, dog's or man's thoughts turn to love. ; ) During my teaching career, we feared the rowdiness and increase in public displays of affection that Spring inevitably brought to the hallways and classrooms.

~~I used the term to note the time of year, and my POV character, Laura Grace, used the term. Here's a portion of the snip in question.
     

       Ten minutes later, the dappled shade and bright patches of vinca and impatiens along the hospital track began their calming medicine. Magnolia blooms heavy with vanilla and lemon scented the warm air. Settling into my rhythm, the beauty of the place captured my mind. A flock of Canadian geese honked at each other as a mother goose, followed by five fluffy goslings, sailed by. The little ones were puffs of downy yellow-gray as their legs worked overtime to keep up with their stately mother. Male mockingbirds strutted their stuff, raising their wings in the spring ritual to show how big they were in hope of attracting the ladies, and I found myself laughing. The sap was rising, just like spring at the high school.

~~I classify FRIENDLY FIRE as Mainstream. At least for the moment. Since it's set in Georgia, I wonder if I need to rephrase the terms Southerners would use in passing for a broader audience, or do they lend color and flavor to my setting? I find myself hesitating at British and Australian terms all the time, but just figure them out by context and read on.

~~What do you think? When is to Southern (or British, or Aussie)  too much? I'm curious about your opinions.