Mold

[HW]

Hi all,

My baby oncidium: Aloha Sunshine 'Blackhole' Maddie Gulbrandson X Kaala (bumble-bee type dancing lady) has some fungus growing on the sphagnum moss when I first acquired it.

I removed the infested moss, soaked the roots in 3% hydrogen peroxide, bleached the pot and repotted in fresh bark mix. A few days later, the mold came back and it came through the drain holes! This suggests the mold was all through the root system.

I have been pouring hydrogen peroxide and sprinkling cinammon powder on the plant everytime the mold comes back for the last few weeks now. The plant is obviously not very happy with me, some of the leaves have turned yellow with brown/black spots and fell off.

Does anyone have any suggestions for getting rid of the mold permanently ? There's been 2 new roots growing since I potted in the bark mix, phew! It's not dead yet, but how would I speed up the plant's recovery from the disease and the harsh treatment I had put it thorough?

Regards,
HW

[Ray]

I would guess that both the fungus and the sick plant are due to the moss being too compressed and not allowing sufficient air flow to the roots. Remedy that and you should be good to go.

[HW]

After a few months in the orchid ICU, my oncidium is still not doing too well. Most of the leaves had turned yellow and dropped off. There's some new roots growing but the plant wobbles quite a bit in the bark mix, so I've decided to repot it in spaghnum moss (should give more support). When I pulled the plant out of the pot, I've confirmed that most of the roots are dead. Is there much hope for my poor plant? Any suggestions as to nursing it back to good health would be appreciated.

HW

[Oscarman]

My new friend is Physan 20 - it has help rescue my recently molded flask of C. dowiana aurea.

I suggest trimming off all dead root material (with sterilized tools, of course) and soaking the plant and spaghnum moss in a Physan 20 solution. Squeeze out the moss well (so it is barely damp), set plant root area in a loose bundle of moss and enclose in a plastic bag with a few hole in it. Keep in moderate light until you see signs of growth and new rooting. If it starts to get dry - mist lightly.

The roots in your pictures seem very wet, perhaps your are keeping the plant too wet?

Good luck with your patient!

[Sandra Billeter]

We have had similar problems with an Onc. and used the "sphag and bag" proceedure successfully. However, my guess is that the original moss medium was way too wet and rotted the roots. Ray said this too! We have repotted Onc.s into bark, coarse perlite, and sphagnum moss mixture and are even trying mesh pots for maximum air flow. So far so good. Whenever we get a "wobbly" plant, we put a root clip across the pot and fasten the plant to it with twist ties. After new roots grow and secure the plant, you can remove the root clip if you want to.

Sandra

[Randy]

HW my Friend,

When I first started growing orchids I killed my fair share of roots. I killed some so badly I thought I should have killed the plants but some most of them lived to tell the tale another day.

The sphag and bag method didn't work for me. Never got a single new root using that method. Here's what I did. First I used nice sterile tools and cut off all those nasty mushy black/brown roots. I then hit all spots where there were cuts with cinnamon, the common kind you get at the grocery store in powdered form. If the plant had some live roots and they were wet I let it sit out for a day until it was dry.

Then I took the smallest clear plastic pot I could find or the smallest clay pot I could find. (The only problem with clay is you can't see the newly developing roots. and the only problem with the plastic pots are they are too deep and don't dry out very quickly.) You will need either some heavy duty string, fishing string or root clips appropriate for the pot for this to keep the plant in place or it will fall out of the new pot.

Fill the majority of the new pot with something that is going to drain really well, a good bark mix, or osmunda or tree fern, something that will drain really well, NOT sphagnum. You will use a little sphag, but not much. Take a small amount of slightly dampened sphagnum (use the mix from below 1 drop KLN/qt of water) and put the plant into this sphag pocket. Only the rizome, not the pseudobulb and lay it on top of what else you have put in your pot. Fasten it in place with either root clips or your heavy duty string, fishing string, etc. You can also mount the plant using this method with the sphag pad.

You will also need some KLN, available from dyna-gro. A great rooting hormone mixture. I got these tiny measuring spoons that really measure a pinch and a couple of other small amounts. I put one drop of KLN into a quart sprayer and use that. Use that sprayer to keep the sphag pad slightly damp.

Here is the most important part WATCH for root growth. Keep using the KLN mixture until you have lots of roots and new pb growths. Once you have lots of roots and some new pb's you can start fertilizing like a regular orchid again.

It's good to know how to save a plant. You learn a lot from the process.

Randy

[HW]

Hello all,

Thanks for all the great tips. My little plant is still struggling. Since the last time I posted, I tried the 'sphag and bag' method without trimming off the old/dead root because the plant had next to no healthy roots, I thought doing so would make it even less stable for potting. Well, it didn't work, the mold came back within a week of being in the bag. I took everything out, bleached and repotted in bark chips, thinking the big air pockets in the mix will prevent further mold growth. I guess it's still too wet for my plant because my fuzzy friend is making an appearance again even though I only water it once every 5 days.

Since bleaching (1/2 tsp per liter) didn't work and I couldn't find Physan-20 at our local stores, my next plan of attack is to trim off the dead roots, where I believe the mold spores reside, and repot. I love the idea of treating it with root-growing hormones, Randy. Thanks. I will try and find KLN and do what you've suggested. Anyone know where I can find Physan or KLN in Toronto, Ontario??

HW

[Ray]

HW, I don't think your issue is mold as much as it is root rot, which a disinfectant won't cure. Don't lose hope though, as plants want to grow roots.

Trim off all of the dead roots, place the plant on top of a bed of damp sphagnum in a plastic bag and seal it up. Keep it warm - a minimum of 20°C - and shady, and it'll grow new roots in a few weeks.

[Randy]

Hi HW,

You did trim off those rotten roots, yes? and hit the wounds with cinnamon? Let it dry for a couple of days? NO WATER for now, until you get the KLN. I'm guessing you are one of those who likes to water?

Both KLN & Physan 20 can be ordered on line from various orchid supply places. Many places which sell orchids via the internet will also sell these products. I would steer clear of Supertrive as I have heard more stories of mutant flowers from it's users than users of anything else. Try the Dyna-gro home page for KLN. Charlies greenhouse, Kellys corner, and many other supply houses will have the Physan.

Do a google search on orchid supplies. You'll probably find one in Canada.

Have a Blessed New Year.
Randy

[HW]

Hi all, I have some exciting news to share. My oncidium was half dead the last time I posted. I ended up trimming off all, yes ALL, off its roots because they were all dead and there's mold/fungus. I stuck it in a home made humidity chamber (a small plastic cup with a medium cup fitted snuggly over top. Punched holes at top and bottom. Then fit the "capsule" in a large cup with water at the bottom) and left it by the window with ambient light.

2 months went by, I was cleaning the room I picked up the chamber for disposal. To my amazement, there are two new growths coming about!

It's too early to tell, but I think they may be new bulb formation or new leaves. There is still a bit of fungus going on but if the plant is surviving, I am not going to bother getting rid of the fungus for now. I am a little surprised that there is no new roots coming though. I am spraying it with a diluted root growing hormone every now and then. Any comments?

HW