young p-bulbs blackening

[Phyrex]

Do I have to be worried about these young p-bulbs starting to blacken at the bottom? The small plant had some black rot so I was a little worried, but then I saw the same thing happen on my C. dowiana. Are the p-bulbs just maturing or should I be careful here? Infestation?? Contagious??

[Cjcorner]

That is perfectly normal. When you see any dried or darkening cover on the bottom simply cut the middle and peel them down and off. Bugs like to use dried matter to hide in and that stuff can hold moisture and can rot your baby p-bulb. I try to watch for and remove the extra dry stuff....on a new plant those old leave sections can hide tiny bugs. I peel a few p-bulbs on a plant i'm thinking of buying....no bugs it's mine.
Hope this helps...
Connie

[ischel1]

Looks like part of the sheath that normally covers a new growth and that's ok. The only area of some concern is in pic #1 looks like you have some necrosis going on there right above the root facing the camera, directly in the middle of the pic, or had you previously cut part of the growth away. In that case necrosis in the surrounding area can be normal. I would use an antifungal and separate from other plants to be sure, but at this point don't do anything drastic ie. cutting away growth.

[clintdawley]

I agree with Connie et. al. Just peel it off. The bracts dry up as the p-bulb matures and are easily removed.

[Phyrex]

or had you previously cut part of the growth away. In that case necrosis in the surrounding area can be normal.

Yes ischel, I had to dump part of the plant since I was worried about black rot. Now I freaked because the new growth was starting to get black also (not mushy though). Then a few days after the one in the right picture (big 'un dowiana) started to do the same and they have never stood next to each other. I hoped it was a normal process of covering the new growth and turning it into a real p-bulb but I had to be sure, so I asked here.

Thanks you guys... and gals of course...

[smartie2000]

I agree with the above

[Phyrex]

This is what the dowiana looks like now. I hope it's just the natural process of maturing the p-bulb but I'm afraid something else is going on.

[wetfeet101b]

The foliar sheaths that cover the young pseudobulbs naturally dry up and turn brown on their own. This is a normal process.
Your desired result will be dry, brittle sheaths that will crumble away on their own in due time.
If it is turning black, then it is a result of the dying sheaths wicking too much water.

Given excessive moisture though, this natural drying up process is not allowed to take its course, or is severely delayed.
What sometimes happens is the dead/dying sheaths continue to take on excess water and slows down the drying process. The result is that the dead sheaths continue to cover the plant longer than it should be and the wet conditions underneath the sheaths begin to harbor fungi, bacteria and all sorts of undesirable residents.

A combination of factors usually lead to this:
1. Excess humidity/moisture.
2. Not enough air circulation to prevent wet spots in the plant.
3. Not enough light*
4. Conditions too cool/cold

* Light influences photosynthesis and plant growth in general. So more light means more plant growth and more water consumption. If the plant uses up more water for its living tissue, then less water will be left in excess for the dead tissue to wick up.

In your pictured orchid, my priority would be to protect the crown. The crown is where the leaf is attached. If the crown rots, you lose the leaf.
The crown is also where the flower spike would emerge from.

I would cut the top of that sheath and gently peel away just enough to expose the crown. Just cut if far enough to prevent any water from pooling in the crown and to allow it access to air circulation.
You do not have to remove the sheath completely.

[clintdawley]

You may want to give your dowiana more light as well. Floppy new growths like that are usually indicative of low light levels.

[Phyrex]

Clint, I know it's lacking a bit of light right now. I need to get some supplemental lighting but it's just not in the budget right now. That said, the plant is growing any way it feels though. I got the other p-bulbs tied up so that they are more vertical than ... chaos.


John, I'm always very careful with watering and I don't think I ever water over the new growth (at least I try very hard not to). The only place where it's really black compared to brown right now is where the new growth attaches to the rhizome. The majority of the rhizome is very dark (like the new one).

Is there any way to force catts to create more new growth than just one next to the latest p-bulb? This guy is going in a straight line with 1 new growth a year where as the Tokyo Magic I have is growing in circles and has put out 6 new growths compared to the dowiana's 1. Even though the dowiana is about 50% larger than the Tokyo Magic I know that it's still a baby and has only flowered once so far (the Tokyo Magic has had at least 4 flowerings already).