wardog - picture would help immensely......

m.a.d.

might be overwatering
depends a LOT on soil type.
the need fast draining soil.

#1 reason for papaya death
is lack of drainage /overwatering
(root-rot)
what part of the country ?

photos would be of great help.

Here is a larger one with the issue. It had 3 times as many leaves and they were darker green before it happened.

Some smaller ones that have lost almost all leaves. They looked extremely healthy up until about 3 weeks ago.

(I live in Central Florida, our soil is very sandy and usually drainage is not an issue)

i am thinking your soil isnt too different from mine.
i have a very fine sand from the mississippi river.. mine may have a tad more in organic matter though.

and i think there lies the problem.
they do like sandy soil, but only if drained very well,, and only if it has at least some organic matter in it.
the grass around it will die on occasion, adding to the organic matter,
BUT, that is only 1 species and its very limited in its mineral makeup.

i would suggest...
micronutrient rich fertilizer.
worm tea or castings. / (or mycorrhizal fungi)
compost... LOTS of compost.
(or at least some kind of mulch)

even just grass clippings, and for the larger ones, pull weeds/grass and mulch/compost about 3ft around the tree. several inches deep.
2ft or so for the small one

i would cut back on the water.
the larger ones should be able to go a week without it
it depends on how moist the soil is a few inches deep.

you can dig a small hole a few feet away and check

also, i would cut down the smaller one. just cut it level with the ground.
they will grow to be big trees and fight over nutrients.
usually papaya are hermaphrodite
(depending on species) years ago this was a big concern, but now, most growers try to plant as much HERM plants as possible.
herm plants produce mostly herm seeds.

i had the same problem as you when i started planting in grass like that.
when i put it in a raised bed and added lots of mulch, the results were dramatically different !

It seems to be a fungus issue. I would cut off the old infected leaves and spray fungicide to the new growth.

WarDog - I think they're not getting ENOUGH water. IN sandy soil, like I also have, the develop this tiny canopy of leaves if they don't get enough water. I have one that looks exactly like your big one. And I have another papaya that is full and lush and I see it's getting MUCH more water than the other one.

IN the summer with sandy soil, you CANNOT give them too much water. How much are you watering now? And if on the smaller ones there is a fungus problem, I would just plant new seeds (or plants) Not sure it's worth all the trouble to treat them since they grow, generally, very well in your climate, except in the winters - now that's a whole other ball game!

maddy

before you water
you should test the soil near it.
its the only way to be sure.

papaya are pretty resilient when it comes to not having water. ive grown about 50 of them to maturity and have about 30 plants now.
over-water symptoms are classic...
older leaves turn yellow and drop.

(no disrespect myamberdog )

root-rot from overwatering is a common killer of papaya.
but, like i said, check the soil a few inches deep to be sure.
--

its very hard to tell about a fungus,
especially without a closeup of leaves etc...
but, it wouldnt be my first guess
and normally fungus only take hold in very humid or wet conditions.

Hello, I grew papayas great last year in the same area that I planted this year's. I've planted using about 40% permiculite for drainage, then organic like worm castings (home made) etc. First, the rains were a challenge as I think this is the most rain I've seen in a long time and less sunshine due to it. But, now, the new leaves have a real weird

look to them. It is happening to my in-ground and potted papaya, I was getting ready to give some away my friends, but I'm not sure they will survive or how to help them. Do you know what this is?