I personally am not a fan of Flex Monthly as it uses historical data, and I’d rather use current data. If I was you, I’d temporarily set everything up on a Fixed Schedule. Then I’d start zone by zone easing into Flex Daily for the lawn. I would make the garden area one of the last to move to Flex Daily as you’ll have a better feel how Flex Daily works/responds by then. You can still use all the weather intelligence features, so if you do get rain, you won’t water.
I would also use a PWS near you rather than just straight weather intelligence. Just check to make sure it is actually recording precipitation (which you won’t be able to do until you get some rain.)
If your garden is watered by drip emitters, that will also take a little more work figuring out your actual Nozzle Inches per Hour. This calculator (developed by another Rachio user in Arizona) will help you get the drip emitters setup. Drip Emitter Calculator for Precipitation Rate & Area
I get more rain than you in NC, but once I got the system dialed in, it has worked very well on my mix of vegetation.
The community here will help if you have more questions.