Two winters ago we went down to Florida for 6 weeks (Feb. 1st-March 15) and camped at about 8 different campgrounds, some near the coasts, some in the central portion of the state. In the case of the central locations (Sebring, Winter Haven, Umatilla, Wesley Chapel) we never made a reservation and had no problem securing a site. We were looking to spend 3-4 nights per campground rather than a long-term stay. All three locations had multiple sites available while we camped there.
One suggestion if you're not planning to make reservations before leaving home: You might try phoning ahead to the next RV park a day or two prior to leaving your current location. That way you aren't going in blind. I would do this if you going to a more popular park or one located in a busy location like Orlando.
One thing that helped was that I did quite a bit of research on 35 different RV parks prior to leaving for our trip. I did this for various geographic areas of the state we planned to visit. I created a chart that included name & address, website & phone number, rates, amenities, comments & ratings from other campers (using RV Park Reviews.com), and actual directions like exit numbers and state routes. This was very helpful and allowed us to plan our next location easily.
2018 Chevy 2500HD Duramax - 2015 Cedar Creek Silverback 29RE
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