Just noticed one of the middle leaves on my Earth Angel looked strange. First time I saw this. I have been watering overhead lately and later in the evening because I just run out of time. This is the only leaf which looks like this. I pulled it off and will watch the plant closely. My question: Do you think this is HVX or due to my poor watering methods of late? FYI: My plant is many years old and about 4 feet across and has been healthy (as far as I know) Any thoughts would be appreciated.

Thanks, Diane