Soil Fertility
Observation/Planning/Testing (what you are doing now)
Earthworks/Swales/Berms/Sunken Beds (this helps with
water)
Soil Life (
Compost, Worm Tea,
Mushroom Slurries, think yogurt probiotics for plants)
Minerals (Rockdust, Minerals, Sea90)
CoverCrop (80% legumes to increase soil fertility aka nitrogen--and usually phosphorous)
Carbon/CoverCrop/WoodChip/Strawbale/BioChar (CL, buy, chop and drop, talk to arborist, I esp like
Biochar for sandy tropical soils, think activated charcoal loosely holding onto minerals for the plant
roots)
Root Inoculation
Plant make food in their leaf and then give it to the roots to find minerals and water. But fungi/mycelium are even better at that, so if plants could give the "sugar/food" to fungi and trade for more concentrated mineral and water it's a win win for everyone. Also buy having lots of "good" microbes already there is no "vacuum for the "bad" critters to fight over and then take over.
https://fungi.com/collections/mycogrow/products/mycogrow_soluble
Fall Planting
It is normally cooler and so plants generally put more
energy into root and less into flowers or shoot, and if you get bare roots, you usually get the best stuff that they have just harvested from the tree farm/nursery.
I would also add that it is a good idea to get a locally adapted cultivar that strives in your Florida soil/temp/climate and not necessarily only get a species/cultivar that only does great in Canada.