ブルーベリー　摘果とクロロシス

I've done a general check of the flower buds, but I left a lot of them, so there's a good amount of fruit. I've been gradually removing the underdeveloped fruit to avoid weakening the trees. There are a few trees planted in the ground that are showing signs of chlorosis. I suspect there's a problem with the roots. I'm trying to see if spraying them with a diluted solution of ferrous ion water and ammonium sulfate will improve the chlorosis. I'll be making a video about this, so please check it out.