onc. twinkle and den. magnum - leaf spot + bulb rot

[Speedracer1084]

Hi Everyone,

I am new to the forums and rather new to orchids. I started off with a few Phalaenopsis and each thrived so I wanted to try some other varieties. I started off with an Oncidium twinkle 'red fantasy' and a Dendrochilum 'magnum' which I am slowly killing. Can anyone provide any advise for me and pintpoint what I think are diseases?

Oncidium twinkle 'red fantasy'

At first I thought the water was being caught in the bulbs like a bowl and I believe rot began setting in. I have since added a fan which I think is keeping it OK. The bulbs look like they have recovered and just have unattractive scar tissue. However, just recently, little black spots with yellow rings are appearing on the leaves and one leaf has already succumbed. Any ideas what these spots are? There is some hope for this one since there is new growth.

Dendrochilum magnum - To be honest, I have no idea how to care for this plant. It just sits there doing nothing except lose leaves. I lost three leaves already and the rest are crinkly. Will the lost ones grow back from the bulb? The roots appear to fine so I don't think over watering is the issue. The bulbs seem to be in decent plump shape so I think under watering isn't the issue either. There also seems to be a black area on one of the leafs too. Any idea what this black area is? Unrelated question, can you cut the spikes after the flower bloomed?

My general treatment for both the spots, the black area, and the rot was to get a fungicide and a fan to create airflow. I also pulled them out and made sure root rot wasn't the cause. Any suggestions would be greatly appreciated. If you need better pictures I can take more.

Pictures are in photobucket album below.

Orchid Diseases pictures by Speedracer1084 - Photobucket

[Zoi2]

Are you misting these plants? That can cause the black spots--bacterial/fungal spots. Increased air circulation will help, they need to dry before sundown.
How often are you watering and what is the potting medium you are using?
If your leaves are crinkley, the plant is probably not getting enough water.
There are several threads on Dendrochilum magnum and Oncidium twinkle here on OB you might use the search for more info.
Joann

	Mistking Looking for a misting system? Look no further. Automated misting systems from MistKing are used by multitude of plant enthusiasts and are perfect for Orchids. Systems feature run dry pumps, ZipDrip valve, adjustable black nozzles, per second control! Automatically mist one growing shelf or a greenhouse full of Orchids. See MistKing testimonials

[Speedracer1084]

Are you misting these plants?
-Nope not misting them.

How often are you watering and what is the potting medium you are using?
-I have my plants in clear pots so I water them when they look dry (probably about once a week). The potting media for the den. is a bark mix with moss. The onc. I believe is bark, charcoal and perlite (didn't change it after purchase).

There are several threads on Dendrochilum magnum and Oncidium twinkle here on OB you might use the search for more info.
-Thanks. I'll look some more. I remember looking up info for the den. magnum before and came up rather empty handed.

	Mistking Looking for a misting system? Look no further. Automated misting systems from MistKing are used by multitude of plant enthusiasts and are perfect for Orchids. Systems feature run dry pumps, ZipDrip valve, adjustable black nozzles, per second control! Automatically mist one growing shelf or a greenhouse full of Orchids. See MistKing testimonials

[Zoi2]

Here are two threads that might be of help to you. Dendrochilum magnum and
Dendrochillum magnum & Dendrochillum glumaceum (2nd try)
Joann