FascistNation, Where are you located? I sprayed my Shiro with Copper in spring and followed up with a few fungal sprays during growing season. Also, I fertilize in dec with phosphus then 2 months later (once I see swell) with fertilome fruit tree fertilizer (19-10-5). During growing season I add nitrogen. I have seen the bruising in all my large California plums so I was thinking it was the humidity/heat. Do you all think I could be over fertilizing? I doubt its a low nutrient lssue since every tree gets at least 2 cups during my three fertilizing cycles. The only thing I can think of is the heat is doing it and a older/larger canopy might help in future. Because if this, I’m consider very little pruning on my fancy plums.