ok, 2 things. first, i should add that some thrip damage (they live inside the sheathe/unfurled leaf) CAN cause dried up edges on the new leaf and then it'll have problems opening and will become distorted. however, that did not seem to be the case with OP judging by pics. but the xanadu example was different: it does not get stuck ever, may be because there is no sharp tip? the leaf is round. but they do pock the leaf up while it's still totally inside. 2nd - what helps with dried up top layer (and i mean just a little dried up, still feeling slightly moist) - is mulch. you can use anything for mulch: gravel, bark, even shredded paper. i like to put a thin layer of long fiber sphagnum moss - since aerial roots love it on philos/anthuriums/syngoniums and also it's very easy to see when it starts drying, so you can rewet in time. that anthurium that kinks for me did not have mulch, it was new and very wet and so i needed to dry it up somewhat. but now i put sphag on it too. and will watch if this finally will solve the problem. i've had a 'greenhouse thrips' year - and been collecting pics of damage on various plants. if only smbody diagnosed it for me last summer !...would've saved me a lot of work. neem won't kill them, they just fester and then explode if you stop spraying for a week or 2. the only thing that works is systemic. and then you need sev applications and then using different systemic ...it's a total pain. but otherwise you can't really get rid of them. i've been spraying with neem twice a week - and also drenching soil ...for months...since last summer. but now after a good dosage of systemic i finally have a new crop of leaves coming clean. here's a leaf with dried up margin damaged by thrips(center one). those lighter stringy areas leading to the ripped edge are also thrip damage. also a few pock-marks here and there. This post was edited by petrushka on Tue, Jun 24, 14 at 11:24

Here's a new roller emerging, it's wedged in there really tight! Sometimes I tease them of some EE, I just can't resist, sometimes I rip one a bit, the damage isn't even remotely similar! I realize this looks alot different than the philo in question, but the scaring along the edge, although smooth on my EE and very toothed and jagged on the philo, looks very similar, to me atleast. I'd like to understand it better, there's ALOT of variables, but I notice it most when it's hot and I'm fertilizing ALOT, so the plants are growing extremely fast. I'd also to very respectfully disagree with rhizo_1, one of the joys I get from gardening is learning about my plants, and attempting to understand them, we all garden for different reasons and in different ways. It's also not very attractive, if something's messing up my plant I want to fix it! I do think you could be onto something, I'm referring to the use of growth regulators or other chems in a large scale greenhouse operation, that, or the fact that it's growing conditions have changed dramatically over the past weeks or months, could have a dramatic affect on a plant! Aroids also react differently to many chems that could be used in the setting they were in. Time for more experimentation!

That looks a lot like the one people plant in the ground here which do grow back bigger each spring, probably a lot of them go untrimmed when partially rotted. I also think yours and these are P. bipinnatifidum. It will hopefully stop rotting since it's not freezing cold anymore. Must be the season for these, I talked this landscaping place out of one for half price Monday because it looks dead after a couple frosts. If it looked as good as yours, I'd post a pic. Of course they weren't sure of the species name. I trimmed all of the dead stuff, repotted, and brought inside. Good luck to us both!! I was out of cinnamon, just plan to let it get really dry now and see how it does. Would there be any point to sprinkling the soil and watering it in whenever it does seem time to water this thing? Seems like probably a moot point by then...?

I think I understand exactly what Lena means. Fast draining soil is not a bad thing. A plant is root bound when there are a lot of roots filling the pot, and not enough of soil medium, and general soil alone is not the answer. Not if the plant is root bound. at least that is part of what I think Lena means. So if you discover you your plant is root bound and repot, read up on the soils recommended here, if you have not already. I have seen such amazing changes in my houseplants that are no longer planted in "general dirt out of the bag" from the big stores. I still use it, but never alone any more, I always add things for better drainage and airflow. lmontestella((NYC) 7b) has given so much great input here.