Another leaf rot question - Orchid Board

Becca · #1 05-30-2007, 12:09 PM

Last week I posted a question on bacterial leaf rot on a dendrobium. I removed all of the problem leaves, which meant I had to take all of the leaves off of one of the canes, I think that is the correct terminology. So that made 3 canes with no leaves and one with leaves. I thought the remaining leaves on the one cane would be okay, but now after about a week the leaves are showing signs of the same problem. What should I do if I have to remove all of it's leaves, as that is how it is looking. Should I just toss the plant or try the sphag-n-bag technique? The plant is one I purchased that arrived very dehydrated and the seller is replacing it, but I still hate just giving up on it. Does anyone have any opinions on what I should do with the plant? I have been misting it with a Physan 20 solution, I thought it would help, but I guess not!

Tindomul · #2 05-30-2007, 01:08 PM

If you want you can sphag and bag it using a technique a member posted about a long long time ago. Basically what she did was cut up the cane into a few pieces and sphag and bagged it. After a few months, each cane had started to grow roots and leaves. I've seen this suggested in a few books as well. Good luck.
There is also a possibility that the bacteria has gone systemic and your plant may be doomed. I would not spend money on trying to save it.

markr · #3 05-30-2007, 01:18 PM

Hi,

First of all, are you sure it's bacterial rot? Many Dendrobiums are deciduous and drop their leaves during cooler, dry weather. Not all do this, but many do. Strange to happen in summer, but you never know - perhaps the stress of shipping and desicated state it arrived in triggered the plant to go dormant... ?

If it really is bacterial or fungal, and you've decided to remove all the affected leaves, I think a Dend has a good chance of bouncing back from a leafless state. Not sure a sphag n' bag is needed, unless it's rootless as well. You'd want to review literature on Dends to make sure you've corrected any cultural problems - good air movement in particular is important when the plant is wet or in humid conditions.

Finally, if this really is a bad case of infection and it continues to spread, I personally would throw the plant away. It's possible to bring a badly infected orchid back to health, but you'll be struggling with a sick plant for some time and it'll be years before it's back to it's former glory, if ever. Unless the particular plant is special to you for some reason, after a certain point it's better to just remove sick plants from your house and replace them. At least, that's my attitude.

Becca · #4 05-30-2007, 01:51 PM

Marker & Tindomul1of9,
Thanks for replying so quickly! I have good air movement from a fan circulating air. It is dry here were I live, we are lucky to get 40% humidity, if that. I do not normally have standing water on the leaves, except if I mist with the Physan 20 solution, but I wouldn't call that standing water. The leafs get spots on them that look brown and mushy and then the leaf starts turning from green to yellow in other area's and then I end up cutting it off. I am trying the Sphag-n-bag technique with several other plants I have received from a particular seller that weren't in such good shape, plus I managed to rot some roots on plants of my own. The root system when I received the plant was dried out since shipped bare root. I soaked the plant, but not for a long time, just about 30 minutes, which probably wasn't enough. I have it planted in Aussie Gold Orchid Mix, but it is hard to tell when it is dry enough to water with, but the roots that poke out at the surface appear to be rotted and I just haven't had the chance to un-pot it and look at it's root system, I am affraid I would have to wack the entire root system off as I have done with a few and then put in sphag-n-bag. I haven't had any results yet using this technique as the plants have only been in it for a couple of weeks, and no new roots yet, but I have problems with white fungus growing on the plants so I usually have to open the bag up and spray the plant down with the Physan 20 solution. I have learned to stop fussing with the plants and just give them the best chance I can, I guess I will just post and update down the road. Thanks a bunch!

Ross · #5 05-30-2007, 02:30 PM

Just an opinion here from a non Dendro person. I have two species of Dendros - one is anosmum and one is aberrans. The anosmum is a deciduous dendro and MUST have a dry winter rest so it can drop all its leaves. Then it blooms on bare canes then starts new growths. About half the Dendro groups are deciduous. The aberrans is a mini that resides in a terrarium with high heat and 90%+ humidity. It is not a deciduous type per se, but still drops the leaves on back bulbs. With this all in mind let me ask you a question. Is your a deciduous type or not? You might need to Google to find out. If it is not, then you have a problem. If it is normally a deciduous type, then my opinion is you are looking at the plant trying to go dormant for a while and rest. Normally in Northern Hemisphere, this is in winter (for anosmum it is end of October to February) but could happen if it has been forced to continue growing year after year. Phalenopsis type Dendros don't need or want a rest period. If yours is one of those, then I have no clue. That is why I quit trying to grow those. All of my Phalenopsis type dendros did just like yours. That's why I call them evil.

Becca · #6 05-30-2007, 02:52 PM

Ross,
I am not sure what to do a search on for the kind of dendrobium I have. I type in the name I have but I am not getting much. It is a Dendrobium Burana Emerald. Does anyone know much about them? It was sent to me in spike, which I cut off to let the plant rest.

Ross · #7 05-30-2007, 03:04 PM

I tried, and like you, got very little. It's like that with hybrids. Try contacting the company or person you got the plant from and see if they can help.

Becca · #8 05-30-2007, 03:10 PM

Ross,
I did some searching and I think the Dendrobium Burana Emerald is a phalaenopsis type from the looks of it,but not sure, which of the two species does it fall into? I have one other of the phaleanopsis type and I don't have any problems with the leaves like this one. They are kept in separate locations, one at work, and one at home. The one at work is the one I am having problems with. I guess I will just have to wait and see what happens. It never occurred to me to look into the type, I found some interesting stuff and I hope to fine a book that will give me more info. Thanks again!

justatypn · #9 05-30-2007, 07:56 PM

Hope you find info on your dend, nothing worse than missing a piece of the puzzle.

Here is the parentage of your Dend Burana Emerald from RHS.
It was registered 7/18/2001
Dendrobium Boon Burana
Dendrobium Burana Green

Ross · #10 05-30-2007, 08:03 PM

Quote:

Originally Posted by justatypn

Hope you find info on your dend, nothing worse than missing a piece of the puzzle.

Here is the parentage of your Dend Burana Emerald from RHS.
It was registered 7/18/2001
Dendrobium Boon Burana
Dendrobium Burana Green

Does this make it a deciduous type or not