also avoid lots of organic stuff in soil. here we also get long rain periods and root rot is very serious problem. the fix here is to use clay soils mixed with coarser minerals like pumice then cat with a small percent of something like coco coir. Here 50%+ coco and you will have rot in summer. Same with various bagged "potting soils". too much organic matter, and mushrooms are the proof.
Like above said, light mixes can be bad in dry weather, we have months of no rain. so that why clay soil is also important. I worst sun we have to water 27cm pots every 2 days or they die.