@Maryl, many thanks for describing so well what I could expect and for water suggestions.
I don't think excessive moisture is the problem, some of the plants are not in full open ground, they are in sort of big vase at ground level; there' s no a big amount of soil, and it dries very quickly; the rest is in a clay/mud soil.
summer is really hot and dry this year.I had to water by hand with a small watering can (6 litres) and I don't think I really over watered them. I alwasy check the soil before watering and I water only when it's dry. It rained for a couple of day but now we still have high temps.The plants seem firmly in the ground, but when I'll have a bit of time I'll try to dig one and check.
@sooby, many thanks to you too.
Inner leaves are floppy, and a lighter green than the outer leaves. There's new growth inside, new leaves that grows in this way.
Maybe it's normal, I don't know, I found some outer leaves bended almost near the base, but they are the oldest and very long so maybe it's fine.
Now, one doubt has come to my mind.. I don't recall exactly when I gave chelated iron to them, but could this be a side effect, in case iron was not needed?
I'm attaching pics of one leaf and a pic of the plant with the new growth I hope you can see the different shades of green. It's not simple to take a good pic!
Many many thanks!