Nasty black and yellow spot at base of leaf. Phalaenopsis
 

I noticed a black spot at the base of this leaf about a week ago. Since then it has grown into this big, sad, sorta rotten looking patch and it just seems to keep growing. I've also noticed a white substance on the top side of the leaf in the past few days. Anyone have any idea what this is, or what I could do to stop it from spreading? The plant seems to be doing fine otherwise.

Thanks in advance for all the help.

it seems some water stayed too long in the foliage and is causing a rot--i would cut off the leaf and spray it with a fungicide...anyone? anyone?:)

a good dose of peroxide to dry it out....

I would remove the leaf and then do the peroxide for sure ...and If I had it after the peroxide had its chance to work use a fungicide or cinnamon

particularly if it is soft and/or wet I would think of bacterial infection. I use excision, peroxide then Cinnamon, but in all honesty have not been too successful in saving these plants.
Nick

Why not get a real fungicide lile Spectracide and water and spray it with it? also with H2O2.
and maybe do not cut the whole leaf but just the rotted section. and maybe keep dry and by a fan for afew days?

Thanks for all the responses guys. I took the leaf off and got a little peroxide in there, and things seem to be looking good. Dry for sure. I'm a little sad to see that white flesh on my biggest plant, but I guess you do what you have to.

I tend to drench my plants when I water them. Being inside plants I assume they could use the bath on top of the watering. Do you guys think this may have been a result of me watering this way, or just bad luck?

the trick is to avoid getting water in the phal's crown and other nooks and crannies on the plant and taking care to remove any excess moisture with a paper towel or q-tip. if you need more humidity, you might want to place the potted plant on a dish of wet gravel. :)