yellow spot on ascocentrum ampullaceum/ and black tip roots

[mollyminiveg]

Hi,

My Ascocentrum ampullaceum "Mr. Del Rei" has been having 2 problems.

1. A yellow spot has developed on one leaf in the last 3 days, and I'm wondering why? Conditions have stayed the same. 75 degrees F during the day/ 50 F at night. About 80% humidity. Full sun from 3-6 pm (when it's sunny). I fertilize lightly once a week and use a drop of superthrive with the fertilizer. I water with rain water usually every day. Sometimes I mist during the day so maybe it's a sun burnt spot???

2. I have two new roots that will grow well for a while then get a black tip. Then it will start to grow again with a healthy green root, and then turn black again. Right now a healthy one is continuing from the black root tip, but I'm wondering why this cycle keeps happening.

Any Ideas?

Thanks

[King_of_orchid_growing:)]

Do you let it dry out between waterings?

The yellow spot on the leaf could just be water getting on the leaf and it was bright out. It may turn green again.

The only thing I can think of with the roots is to let the roots dry out a bit.

[nenella]

Yes I too agree with King about both 'problems'
I wouldn't worry too much, as even though the roots have a darker mark (ring) on them they seem to be otherwise healthy & growing.The old ends of the root (ie: the black parts, now) probably got left damp a bit too long once or twice..? Just keep an eye on them & don't let them stay 'wet' too long... Also it may just be the bark colouring them up as the tips stayed too long on extra wet bark?....
Someone else may have other ideas? Keep us posted!

[Raphael]

This happens with some of my Vandaceous- it's fungal and caused by inconsistent culture. When that happens with the root, it is also an indication of inconsistentcies in your culture. I find that my Asocentrum ampullaceum (I have several) display both these symptoms when the humidity and temperature is lower than they prefer. Combine that with improper watering, and you've got a fungal problem!

[mollyminiveg]

Thanks, for your responses!

A fungal problem is what I was afraid of, but I will water less. Its' true my conditions are not consistent. I've been thinking of getting lights, because it's often cloudy here. Humidity has been high, but it's been a cold summer in general.
Thanks again for your help.

[mollyminiveg]

Thanks, for your responses!

A fungal problem is what I was afraid of, but I will water less. Its' true my conditions are not consistent. I've been thinking of getting lights, because it's often cloudy here. Humidity has been high, but it's been a cold summer. Probably too cold for my Ascocentrum.
Thanks again for your help.

[Raphael]

Yes, especially the ampullaceum! They like it toasty and very bright!