What has happened to the tips of these fern fronds?
I've got some huge bracken-type ferns, in big pots. Had them for decades. I cut them back in Feb every year and they come up looking fabulous. They were doing that this year until suddenly today I noticed that a lot of the tips are looking black and broken. They're not dry, they're watered regularly, they are in a shady corner and don't get too much sun, nothing's been sprayed in the area, and there don't appear to be any insects involved. They haven't been over-watered either and anyway the damage doesn't look like either dryness or too damp. I can't find anything online, all the articles that come up are about drying out (or sooty mould, but it really doesn't look like that, no insects and confined to tips of fronds, not all sticky). What it looks like is a mixture of breakage and something nasty on them, but how can that be? Waaah, I adore these ferns! Anyone seen anything like this please?