after the first year of planting .. and perhaps a drink in the second year if there is drought .... no tree really needs constant watering .. unless you are in the desert ... which brings us to.. where are you .. big city name good enough ...

otherwise.. water a tree when it needs it .. not on a schedule .. and a well established tree really should be able to cope.. unless you are growing things way out of their normal range ...

may as well tell us about your soil type.. and how it perks.. etc ... so we can decide if that is an issue ...

and tell us how big the trees are ... size matters ....

do you plan on properly mulching the plants???

here is a good primer below on tree care : https://sites.google.com/site/tnarboretum/Home/planting-a-tree-or-shrub

avoid amending the planting hole .. imo ...

ken

ps: i never had much luck with the 2..3..or 4 in one plants ... i wish you luck with those ...

pps: there is a good sized orchard a mile or so away from me.. and i am positive.. they do not water ... but for the grace of God ...

a second though..

i did have a row of 6 inch green giant arbs on drip.. on my sand ... and i watered about once a week for 8 hours ... and in drought the second year.. and never again ... i wanted the entire root mass of my tiny babes to have water in my sand.. and thats how long it took for the emitters to spread the water.. from one emitter to the next ...

my point being.. you have to understand your soil.. and its drainage ... to understand how to properly apply the water any given plant will need ...

you ought to perk your soil if you have never done so ... it will provide you a lot of info ...

ken, again ....

https://duckduckgo.com/?q=perk+test+for+garden+soil&t=ffnt&ia=web

I'm near Panama Beach Florida my soil perks 2.5" per hour sandy loam so it's got a nice topsoil for 12 in with a clay and sand type below. The trees are bare root 2-year-olds. I planned on using plastic mulch around each tree 3 ft diameter with drip irrigation underneath the mulch. I figured I would put adjustable emitters around each tree that way I could adjust more or less for each tree.

good ... your knowledge level is beyond just throwing water at them ...

i have no experience in FL hort ... so i am just going to leave you with one more thought ... maybe 2.. lol ... coffee buzz.. sometimes i cant stop myself .. lol ...

you put down your irrigation ... and run it on your best estimate of what they need ... and then you use a hand trowel or tablespoon to dig small holes.. a few inches deep .. and FIND OUT how water is moving thru your soil ... and adjust accordingly ...

no one can really give you definitive answers about how this will all work.. in your soil.. in your climate .. in your yard ... so you just have to find out ... that was how i found out how long it took for the water to spread thru my sand between the GGs i mentioned above ...

ok.. i will add one other idea ... citrus and fruit is BIG in FL ... so i bet your local extension or Ag office ought to have a lot of info available .. find it and use it ... i will start you off at the links below ...

good luck.. and have fun ...

ken

scroll down a bit: https://duckduckgo.com/?t=ffnt&q=irrigating+fruit+trees+in+FL&ia=web

extension offices: https://duckduckgo.com/?q=irrigating+fruit+FL+extension+&t=ffnt&ia=web

this might be the bazinga: https://duckduckgo.com/?q=irrigating+fruit+FL+agriculture&t=ffnt&ia=web