Thanks for the information. I’m wondering if you have any trees on Bud9 and if they ever reached the size that you expected. Most of mine never reached the top wire which surprised the Apple PHD who had a lot of experience with B9 in Western NC but very little with Apples in the Piedmont.
We rely on drip irrigation too, but I was interested if the rivers have any tendency to moderate the frosts during peach bloom and if it has any impact on the humidity in the orchard.
I’d like to add to what you mentioned by suggesting citation rootstock for stone fruit in locations with poor soil. My native soil is heavy clay, yet with the citation rootstock plums, nectarines and peaches do very well.
I’d imagine my sand would want the opposite of that rootstock, but it’s just speculative. Sand acting the opposite of heavy clay, I struggle with moisture retention more than anything.
Late to the party, but I’m thinking about getting two apple trees for my yard in Durham. I’m thinking a sundance and maybe an old southern apple- do you have any recommendations, based on your expereince about southern apples (limbertwigs, etc.) that do well in Durham and that would pollinize and be pollinized by a sundance tree? Thanks much for the help!
Spare yourself now and just get some jujubes instead 
“Sometimes the hardest things in life are the things most worth doing.” 
You can see which apples @applefarmer has: Many Rivers Farm. Looks like a nice place! I’d go visit!
Also, there’s lots of websites with pollinator info (I think there are some in the guides as well). Here is one: The Pollenizer - Cummins Nursery - Fruit Trees, Scions, and Rootstocks for Apples, Pears, Cherries, Plums, Peaches, and Nectarines..
I’m north of you but also in a humid summer area. I heard a lot about how hard it would be to grow stone fruit, but I was willing to spray so I tried and decided it wasn’t so bad. I managed using a variation of @alan’s synthetic spray guide +3-4 extra sprays (1-2 were oil/copper in dormant season).
I have found that apples are actually more difficult. =( That doesn’t mean you shouldn’t try - but do plan on some spraying.
Also, go dig up some soil and do a jar test (and a pH test). Based on what your neighbors are saying you may want to choose rootstock based on that or change your plans.
I used to live in Franklin county NC, now Surry. I grew apples and my father did as well.
As long as you’re willing to spray fungicide, you’ll be ok if you don’t select blight bombs. If no one around you grows apples, you may not have so much FB pressure. Cedar rust is an issue to plan around. Sweet apples tend to be more prone to rots and yellow jacket/hornet issues. Yellow/green apples tend to be more prone to rust.
My father grew many different varieties, but the Ark Black and Earliblaze did well in his orchard. Avoid Freedom (BR), Empire (BR), Newtown Pippin (FB), Williams Favorite (FB), Carolina Red June (FB), Grimes Golden.
I grew about 20 varieties there, but some never made it to the fruiting state before I moved.
Summer Rambo, Cortland, Victoria Limbertwig, Stayman, Ark Black proved to be very durable during the drought and heat years of 2005 and 2007. The Blue Ridge King would be a perfect apple for the area, but it has a blight issue. The Royal Limbertwig did ok. I don’t like the VA Beauty. Winter Terry did pretty good, but the apples are small.
Cripps Pink may be good option.
Put some in and try them. All my plums got black knot and were pulled out. But no spraying and didn’t know what knot was until too late. Apples grow but are all sickly. Even so, they taste great when the tree does produce. I will retry plums and be on the job to see any black knot. If it is a no-go, then there is my answer.
And put in a jujube or two as a backup 
for the bad years when the apples are lacking
Thanks! This is super helpful!