Re: prepping a boat for long-term storage in moist/hot FL, I would first suggest you look into a dehumidifier. If placed amidships and with a few cabin fans to help it out (if you''re okay with leaving the DC circuits energized), it will help immensely to keep down fungi growth.
Other steps I''d encourage you to consider are:
1. Cover all ports and hatches (either simply using curtains or with aluminum foil to save the curtains from the U/V)
2. After shutting down the reefer, do a thorough galley clean with disinfectant, sealing inside jars or plastic containers any food not in a can.
3. Stuff all thru-hulls and seal any other openings as best you can to keep the critters out; you''ll find this a bit challenging where the dehumidifier is left to drain its condensate (galley sink, most likely) so perhaps in that case you''ll stuff the rag around the drain line at the sink.
4. If considering a cover, make sure it''s previously demonstrated it can be used for extended periods with minimal chafe; don''t forget that thunderstorms and violent winds are possible. You may find a yard will prohibit use of awnings
5. Every bin, locker, drawer and door should be left open in order to maximize air circulation. Ditto cabin sole hatches
I hadn''t heard the caution about the cane fields depositing debris on boats, and I''m not sure I believe it. Glades is on the outskirts of Ft. Myers, not well up the Caloosahatchie R. I''d check that out further.
Good luck! You might also consider paying for a below-decks check once or twice early in the storage period, just to add peace of mind for only a small cost.