Choose wineries that fit together.
Start with one must-visit winery, then add nearby reservations. Crossing wine country repeatedly turns tasting time into windshield time.
Ask each winery about group size, deposits, food and arrival rules. Do not assume a reservation can be stretched if the group arrives late.
Make food and water part of the itinerary.
Plan a real meal rather than hoping the group finds something between tastings. Add water onboard and give everyone time to eat.
If the day runs long, make the final winery optional. Protecting the earlier reservations keeps the outing enjoyable.
Account for the complete San Diego round trip.
Pickup location, freeway traffic, winery driveways and the return all take time. Set the home arrival expectation before booking the first tasting.
For larger groups, confirm whether winery entrances can accommodate the selected vehicle.