My Yucca tree has alot of black on the tips of the leaves, any idea what it could be and how to treat it?

I've seen rust on other yucca plants before but never black, I thought if not a disease it could perhaps be excess nitrogen but I just don't know and the plant looks otherwise extremely healthy and is growing at a thenominal rate !!

My Yucca tree has alot of black on the tips of the leaves, any idea what it could be and how to treat it?
Couple of thoughts - though it would be easier to know whether this is an indoor Yucca or is outdoors.





Is it external to the leaves, ie. can it be washed/scaped off etc? Is there any sticky deposit as well?


If so, it could be mould that is growing, often ontop of sticky


deposits from aphids.





Usually the tips of leaves is where it is hardest to get water to, and thus often dry out, especially with out centrally heated homes in winter. If it is this, you should also notice that the leaf is drier here, as it has dried up.





Otherwise, it could be leaf rot, perhaps again due to less than perfect conditions in winter. You phenomenal growth rate could mean this is nonsense, but I'm not sure if this is in part due to poor light and it's reaching up and up to get more of it, coupled with some decay.





Just some quick thoughts. Get back and metion if it is indoors or outdoors, as this will help alot.





Good luck! Rob
Reply:they were exposed to below freezing temps . the black is dead plant , trim those off and it will be fine
Reply:I believe that the moisture in the plant does not reach the tip of the leaves.


I have noticed this also in one household but as you said the plant is very healthy.


Would it be a good idea do you think if you sponge the tip of the leaves now %26amp; again before they turn black?


Worth considering?
Reply:could be fungal, they dont like moisture on their leaves and being kept in shade.





yuccas like full sun and a bit of a breeze now and again