This is actually the first multiflora that I have managed to get this far with. so you can believe that I'm excited It's also my biggest paph with a leaf span of 81 cm.
Robert Barry is roth x Julius.
Most of the macro and micro nutrients are more bioavailable at lower pH than higher, but symptoms of overdose often look a lot like under dose. This is pretty striking looking foliage. The green parts are a pretty healthy shade of green, but the yellow is intense in the older leaves. The majority of Paphs (and probably all of the multis) probably don't appreciate pH's below 5 - 5.5 for whatever reason, and well seasoned moss could have a pH lower than 5. I also think its a nutrient imbalance associated with low pH, but I'm not sure if its over or under dosed.Hmmm. I'd think direct effects of bright light would yellow up the upper leaves before the lower ones. Yellow lower leaves is likely nutrient defficiency IMO. Although over time, bright light driving photosynthesis would require nutrients and if their aren't enough, the plant moves them from older portions to newer ones. Not that you're underfeeding though! It's in sphagnum moss. Might be a low pH at the roots giving low nutrient *availability*??? If you like how your plants grow in sphag, try a foliar feed once in a while with a final pH (after fertilizer added) between 5.8 and 6.8?