It's not always peaches and cream

[LJA]

So, I really appreciated all the comments you guys made on my growing in the Milt thread. I'm a professional at this point, and I wouldn't expect anything less of myself than primo plants.

HOWEVER: Providing the kind of environment that allows orchids to do their best also provides the kind of environment that allows their fungal and bacterial enemies to thrive as well. That's the constant battle, and it's one we don't always win.

We all like showing off our accomplishments, but I think it's important to remind people every once in a while that even quality growers get the same issues everyone else does. Here are a couple examples.

This first one is a Zootropheon atropurpurea that needs to be kept sopping, and that's exactly the kind of environment that fungus adores. I have cut, sprayed, cut, sprayed, and cut and sprayed this thing, and it *still* keeps developing fungal lesions that can make an orchid's foliage look like it was attacked by a biblical plague.

The second pic is a Paph. with leaf tip dieback, again fungal. I've cut and cut and sprayed, and it just won't go away. Obviously, these plants can't go out to the public, so it's doubly galling that they're going to have to be grown out fungus-free for several years until they're appropriate for retail consumption again. (By the way, you can differentiate between fungal dieback and salt buildup dieback by how the leaf tips look. Salt toxicity that rushed to the ends of the leaves will create brown leaf tips with a hard edge between the dead brown part and the healthy green part. Fungal dieback will result in brown leaf tips gradually fading through chlorosis to yellow and finally green where the leaf is still healthy, like you see here. There's no hard line between the brown and the green.)

So while everyone who's into these things can (and should, I think) go to whatever effort is necessary to grow as well as they possibly can, sometimes the effort can be in vain, and you have to take the bad with the good.

[Piper]

Thanks Louis - that's good info. Any good anti-fungal treatments for that sort of problem?

Julie

[MikeWA]

Great info Louis.

I remember Peaches-n-Cream. Man, that was not a good flashback!

[RSJ]

Thanks for the morale boost and the pictures, Louis. Also very helpful to know about the hard-line for salt problems vs fungal issues. Didn't know that trick of telling the difference.

When you talk about fungal lesions, are those little black spots on the leaves in the first pic, and particularly common on Sharry Baby and the like, considered fungal lesions?

RSJ

[bench72]

very informative thread Louis, esp backed up with photos.

The fungal die-back on the Paph just got me on the right diagnosis for my Paph Honey Thankfully only one leaf..

so going by other post... cut below the yellow and sprinkle with cinnamon right?

Cheers
Tim

[peteMc]

thank you Louis.

just shipped off my paphs so they'll be well cared for, fortunately they didn't have fungus...

great troubleshooting tips for the file...


p

[LJA]

...you guys are welcome--glad the info could help some.

Tim, yes, cut an inch below the yellow and cinnamon the cut. Sometimes that fixes it, sometimes the stuff keeps on growing downward....

When you talk about fungal lesions, are those little black spots on the leaves in the first pic, and particularly common on Sharry Baby and the like, considered fungal lesions?

RSJ

Very big debate going on about that. In the first pic, all the spots are fungal. Fungicide should take care of it, but the rate I'm using (3 weeks in a row, every three months) doesn't seem to be enough for these two.

As far as the leaf-tip peppering on Sharry Baby and other intergenerics, research is underway to determine if those aren't, in fact, viral lesions and not fungal ones. All the hundreds of thousands of Sharry Baby 'Sweet Fragrance' out there are mericlones, and it's been postulated that the original plant from which all these clones were produced was virused, and that this virus has been transfered to all the divisions. Some people say that the cloning process doesn't transmit virus. Still others claim that with enough spraying, cutting, and growing out, you can get rid of the spots, implying fungus. And yet others, culturing these lesions in labs and examining them under microscopes, have found absolutely no evidence of fungus at all.

So that's the current state of affairs as I know it, and I don't think there's been any resolution yet. I personally cannot grow Sharry Baby (or Linda Isler 'Red', for that matter) without getting that leaf tip peppering; it appears on new growth just as the bulb matures and starts to throw a spike, never before, and it's worse on plants that are given high light. I also don't know any other grower personally who has been able to bloom Sharry Baby without getting those spots, and a lot of people (me included) have just grown to accept the spots as a side effect of the plant getting enough light to bloom well. So most folks just resign themselves to the spotting under the justification that "orchids aren't grown for their foliage anyway." If there's some way to keep the spotting from happening and still bloom the plant, I'd sure like to know--new growers get especially freaked out when they see that rash on the leaf tips, and if there's some way to avoid it....

[sadie]

Its always nice to see that EVERYONE has a few challenges -- (we all do, just not everyone is willing to admit it