Hi Toby. I'm from New England and used to temperate conditions.
I've decided to buy some land in the tropics/subtropics, and am investigating parcels in different areas.
Some I'm considering are in Florida. They're affordable because the soil is sandy and the land barren.
My goal is to buy about 5 acres and grow a forest garden for myself and use the surplus to sell in markets. I've taken a PDC and am familiar with the basics of design, but need more info on implementation in a barren tropical setting.
Arrangement of trees on site, use and planting and choice of cover crops, how to arrange forest lands around swales, etc.
I'm curious to know if you have specific suggestions for books covering tropical forest gardens. Is the 2 part Edible Forest Gardens book applicable to the tropics/subtropics?
(IMHO) When asking questions about sustainable (and profitable) food forests in Florida, get used to the sound of crickets chirping. That's about all the advice you are going to get.
I am by no means an expert. My only knowledge is from a few years observing our local environment and listening to the advice of others.
I've turned my attention from broad scale food forests to backyard food forest, or horticulture maybe a more precise term. And fortunately for me I have an interest in greywater and rain harvesting.
Although some of my early experiments are showing signs of success I am skeptical that a food forest in Florida sand would survive a year or two without a significant amount of inputs.
Some random thoughts:
If you can harvest the greywater and a large amount of pavement runoff from a mobile home park, say 200 units, you may be able to pipe in enough nutrient to make a sizable and profitable food forest.
Another idea may be to use your greywater and blackwater put into a built lagoon. This could be used to grow fodder for livestock.... And think bees, always think about the bees. You won't get anything accomplished without bees.
Another approach may be to truck in large amounts of municipal shredded mulch from local towns. Citrus county has a good program. Use that as bedding for some kind of livestock such as chickens or turkeys. After exposure to manure and some good turning by chickens, etc, work that into some garden beds and eventually your perimeter food forest.
I don't believe any single approach will work. It will take a variety of disciplines and years of experimentation. Think bees, aquaculture, poultry, ducks, turkeys, perhaps a goat. And perhaps consider participation in some kind of fishing, or managed hunting of wild hog and turkeys.
You may want to follow Jack Spirko and The Survival Podcast. Tons of great information on sustainable living and permaculture that is relevant to the Florida landscape.
Another important thing to remember is the frequency of frost. The frost belt can shift dramatically from decade to decade. But generally speaking the zone south of Tampa Bay along the west coast is frost free. And the area inland south of highway 60 is frost free with a few exceptions. Inland lowlands can become frosty. But that just determines your selection of elements.
I consider sustainable permaculture in Florida and the Gulf Coast area to be one of the greatest and possibly most rewarding science and occupation of the new century.
Also, many Mediterranean plants work fairly well in Florida. Sandy soil is also a big problem for me. Have added lots of leaves that the neighbors seem to think of as a problem instead of a solution. White clover just got seeded in and is sprouting, pigeon peas do fine in the sandy soil and are starting to provide a good mulch. Swales to retain water and deep-rooted perennials to use the water are a good combination. Sickle-pod and spanish needle are two very common 'weeds' here ... many people hate them for various reasons, but they are pioneer species that rebuild the soil in the early stages of succession.
Lemongrass quickly makes a decent "no-dig swale" - planted right, it can form a solid barrier that traps water and sediment. In the north of Florida, the West Indian strains are better than the East Indian strains (much more cold resistant), but they are not as good as the East Indian strains for culinary uses.
Citrus and avocado have been two good choices, but both face some serious medium-term issues due to introduced diseases.
Here in the north, olives, pomegranates, figs, mulberries, loquat, pears, plums all work, along with persimmon, paw-paw, cherry of the rio grande, jaboticaba, sapote, muscadine grape, feijoa.
I was just reading about a grower's coop for hybrid chestnut being formed in central Fl to do processing and marketing, and then there are pecans. Hybrid hazelnuts might work if the right genetics were used ... most strains were developed up north and have not been tested here.
Various bamboos do well (too well, according to some) and can provide edible shoots and wood.
Bananas, chayamansa, chayote/mirliton, and cassava are fair to marginal or poor in the north of the state, but do better where the frost is not so severe. Have had moringa for two seasons, it also seems to under-perform compared to its reputation, may be a soil issue. Jerusalem artichokes and mints have reputation for taking over once established, but my experience is that they fade out in a season or two.
One traffic intersection I pass by regularly has an island filled with prickly pear, and that small space is now packed with a few hundred pounds of cactus pear fruit - too much traffic there for me to think favorably about eating them, but clear proof that Opuntia does well here.
For caffeine lovers and a cash crop, there is tea (Camellia sinensis) and the native Yaupon.