Hi,
An extremely annoying problem. My Den. King's new leaves start great, there are currently 5 new canes, but when starting to mature, I see some white scales, they aren't sticky, cannot be removed. Looks a little like water calcium, then tip dryness, then, yellowing tips, then death of the leaves...
Well I’m not sure. Mites hate water, so I’ve heard. So I was trying to increase humidity, mist, but no use..also, this happens only on the new canes. Mature leaves are ok.