Is this crown rot on a phal? & is it salvageable? - Orchid Board

OzPhal · #1 09-09-2009, 03:16 AM

Hey Everybody,

I recently purchased some Phals from eBay - beautiful plants - each main plant had a side growth of much the same size as the main. Awesome root system on arrival - and evidence of proliferous flowering in the past (even this season). A few days after I received the plant I noticed the top leaf on the main plant of one of them start to yellow and then I noticed a black patch starting to appear... I applied some fungicide but no success - it has spread.

My question:

1) Is this crown rot?
2) Is the main plant salvageable?
3) As there is what appears to have been a basal keiki grown (which is much the same size as the main plant) is there anything i should do to prevent the rot from impacting on the second plant?

Any advice is appreciated

BikerDoc5968 · #2 09-09-2009, 08:36 AM

Looking at the 1st pic, it "appears to be" crown rot. In the 2nd pic, lower leaves turning yellow could just be normal aging of a phal and loss of leaves. If it is crown rot, many use cinnamon in the crown as a fungicide. As the 2nd pic looks now, you might not be able to save the main plant but if there are roots on the basilar keiki, this should not be affected and would remove it to its own growing area. In the future, you may want to consider using Physan 20 or RD-20 as a monthly spray to combat problems with crown rot. I do this as a proactive way of keeping things clean in the GH. I used to have a real problem with crown rot...lost several phals... not that I couldn't have it again but since using RD-20 somewhat regularly things have been significantly better. Also don't allow water to set in the crown of any of your orchids overnight. If you are watering/misting, try to do it in the early part of the day so things can dry out.

stefpix · #3 09-09-2009, 08:49 AM

Would using peroxide instead of physan work as a monthly preventive misting?

stefano

BikerDoc5968 · #4 09-09-2009, 09:00 AM

Quote:

Originally Posted by stefpix

Would using peroxide instead of physan work as a monthly preventive misting?

stefano

Don't have any experience using H2O2 as preventative care for crown rot.

King_of_orchid_growing:) · #5 09-09-2009, 08:47 PM

Quote:

Originally Posted by stefpix

Would using peroxide instead of physan work as a monthly preventive misting?

stefano

This course of action is not necessary at all. It's poor maintenance practices that have led up to this issue, not disease.

A healthy plant has an immune system that is quite capable of handling many disease organisms perfectly fine.

Here's a little chemistry tid bit. H2O2 is not just a disinfectant but a bleaching agent as well.

OzPhal · #6 09-09-2009, 09:03 PM

Quote:

Originally Posted by King_of_orchid_growing:)

Here's a little chemistry tid bit. H2O2 is not just a disinfectant but a bleaching agent as well.

Try accidentally spilling some lab grade H2O2 on your hands and see what happens - it's interesting! hurts too and is absolutely not something i recommend.

Note to self - if a lab tech puts a bottle of H2O2 in the staff refrigerator (which you hadnt seen prior to this) don't assume that the water at the base of the refrigerator is just water - therefore don't go and grab a paper towel to wipe it up with your hands coz the H2O2 soaks through the paper towel and bleaches your skin... needless to say i didnt see the lab tech after that event!

King_of_orchid_growing:) · #7 09-09-2009, 09:10 PM

Quote:

Originally Posted by OzPhal

Try accidentally spilling some lab grade H2O2 on your hands and see what happens - it's interesting! hurts too and is absolutely not something i recommend.

Note to self - if a lab tech puts a bottle of H2O2 in the staff refrigerator (which you hadnt seen prior to this) don't assume that the water at the base of the refrigerator is just water - therefore don't go and grab a paper towel to wipe it up with your hands coz the H2O2 soaks through the paper towel and bleaches your skin... needless to say i didnt see the lab tech after that event!

Well noted!

OzPhal · #8 09-09-2009, 09:03 AM

So would you seperate the basl keiki from the main plant and discard the main plant? Could i try cutting the damaged leaf off, treating it with cinnamon, and seeing if it will sne dup a new leaf?

BikerDoc5968 · #9 09-09-2009, 09:27 AM

For now, let's say this is crown rot. From the looks of that top leaf, I doubt it will grow anything from the top. If the rot has gone down into the stem, then for all practical purposes that portion is history...sorry. This doesn't mean the keiki will die as long as it has a good root base. So if the main plant is not salvageable, yes, I would remove the keiki and grow it on its own in a new pot. The cinnamon won't do much for the main plant if the rot has extended into the stem. The point of trying to save the main plant is the hope that it might throw more keikis.

OzPhal · #10 09-09-2009, 05:26 PM

Thanks Biker,

I've had a closer look at the spot this morning - it doesnt appear to have extended down the stem rather it is a black spot on the leave at the base of it. Is it worth trying to dissect that leave out and remove as much of the rot as possible and then treat it and cross my fingers?