I nearly lost my dwarf Cavendish to this burnt-leaf problem. Weird too since the Giant Sweet plantain wasnt that far from it & both get fertilized the same. In desparation, I finally dug it up, cleaned it up, & cut the dirt in the mound with a lot of sand & new compost. I replanted it (without fertilizing) and the new leaves weren't nearly as burned. That was early last month, now it's so healthy looking, ya can't tell there was a problem and it sent up a very healthy pup. The Plantain was never affected.
I'm not saying it was definitely over-fertilized BUT I will say that the same soil mix was used in both mounds, same fertilizer too. My conclusion was simply that Cavendish requires less fertilizer than a Plantain. Could be wrong but that's my best guess.
Total LOL on that previous post
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