What is this weird fungus in my nepenthes media?

[spiffyzha]

So I've got this weird fungus-looking stuff growing in the media with several of my nepenthes. It's most noticeable in the pot with N. 'St. Gaya'.



Possibly related: this St. Gaya is pretty sickly.



It's been sickly for quite a while, actually. I've treated it for thrips and spider mites, and maybe 6 months ago I repotted it into a new set of media, thinking it was sure to start recovering soon. Now it's got this weird white stuff growing beside it, and somehow looks more unhealthy than ever. I didn't notice it immediately because, well, this plant used to have a lot more leaves. The media is full of sulfur and ceylon cinnamon, so whatever this stuff is, it apparently doesn't mind either of those things.

My N. 'St. Gaya' pot was hit the worst, but it's certainly not the only one. Here's what I think must be the same thing growing just on the tips of the sphagnum near N. ceciliae. N. ceciliae is also pretty unhealthy.



...And here it (probably) is in my N. alata pot:

You can even see it growing on the stem itself. That seems bad, but on the other hand, N. alata is (currently) doing fine.

Anyway, this stupid white stuff seems to be growing to varying degrees in several of my other nepenthes pots as well, most of which I potted up around the same time.

So obviously these guys are going to get a full repot, but, like... what is this stuff? Has anyone seen it before? Is it actually making my plants sick, or is that just a coincidence? Am I doing something obviously stupid that encourages it to grow?

 

[Lloyd Gordon]

Scarily, some of the white stuff looks like mealy bugs. I think with these plants, you're going to have to unpot them, remove all the media and inspect the roots carefully. Remove any dead or diseased looking roots. Post pictures of the roots before you put them back into new media.

 

[spiffyzha]

Hm... I don't think it's mealybugs? At least, *most* of it isn't mealybugs. The white fungus-y stuff seems to primarily accumulate on things that are already dead.

Though, looking at the pics of N. 'St. Gaya' leaves again, I do see why one might conclude "mealybugs". I think it's just dust, but I'll be able to get a better look at it tomorrow with natural light.

Honestly, it would be a huge relief if it was just mealybugs and the fungus was harmless, because I have a better idea of what to do about the mealybugs.

 

[spiffyzha]

So the roots look basically fine, at least to my eye. Here's N. 'St. Gaya' immediately after being unpotted, and later after I tried to rinse the roots off a bit.



And here it is settling in to its new media, which is mostly coco chunk based this time.


It's still pretty sickly looking.


I can't find any bugs on it, even using the loupe. But if it were thrips, for example, I'd likely still miss them. (Does this look like thrips to people? At this point it's my top theory. ) The plants immediately adjacent to it seem unaffected, so I don't know. I'm giving it a course of Willy's systemic now, so maybe that will just magically fix everything.

N. ceciliae (one of the other plants with obvious white stuff growing in the media) actually seems to be making a recovery now after moving it indoors. (N. 'St. Gaya' hasn't been outdoors at all this season.) And.... that's all the plants that both have white stuff growing in the media *and* have taken an apparent hit to their health.

So, it's seeming more plausible that whatever's killing my St. Gaya might not be the weird fungus in the media afterall. Guess I'll just have to wait and see if things improve. :\

 

[spiffyzha]

Bump.

I still don't know what this stuff is, but it's killed several of my neps with no sign of stopping, and now a couple of my pings as well.

It feels gritty like salt. It doesn't mind cinnamon, sulfur, or Willy's systemic. The only thing I've found to potentially slow it down is doing a full re-pot, but the plant still ends up being infected a good fraction of the time. (Is it potentially in my reserve of potting media somehow?? Ugh...) If I wait til the plant is showing symptoms, it will die anyway with the traumatic re-potting.

The N. St. Gaya and N. ceciliae mentioned above are long dead. N. alata was a pretty big plant to start with, but it will also drop dead any day now:


Here's another pic of that gritty white stuff growing on the stem of N. (ventricosa x sibuyanensis) x burkei:


Any ideas? At this point I'm about ready to just burn a bunch of otherwise healthy-looking plants where I can see this stuff has started growing on the media.

 

[Lloyd Gordon]

It's hard to tell. It sort of looks like salt build up. If you can collect the white stuff, put it into a little bit of water and see what happens.

 

[Dieseldr]

It's hard to tell. It sort of looks like salt build up. If you can collect the white stuff, put it into a little bit of water and see what happens.

That is a really smart idea Lloyd!

 

[WillyCKH]

Occasional top watering, flooding & flushing can help reduce the mineral buildups. You can also keep a few hardy & easy plants in the same water tray to help taking up some unused minerals in the soil as well.

 

[spiffyzha]

It's hard to tell. It sort of looks like salt build up. If you can collect the white stuff, put it into a little bit of water and see what happens.

Worth a try. I'll report back on how it goes.

Occasional top watering, flooding & flushing can help reduce the mineral buildups. You can also keep a few hardy & easy plants in the same water tray to help taking up some unused minerals in the soil as well.

I'll admit -- it really *does* have the appearance and texture of salt buildup. I'd been sort-of discounting that possibility though because this stuff doesn't seem to care how the plants involved are watered. I think it can be passed by plants sitting in the same tray of water, yes, but several of my dead nepenthes that had this stuff growing in the media were set up as strictly "water only from the top and by flushing a bunch of water through" plants.

Any recommendations for plants that don't mind a lack of fertilizer? All the utricularia and mosses I've tried to do that with have eventually either died from a lack of nutrients, or, if I feed them, by being overgrown with algae.

 

[Lloyd Gordon]

I only feed using FDBW or Tetra colour bits. Or for the smallest CP's, foliage feeding of lower strength Schultz orchid fertilizer. I never root feed anything except the Orchid solution for Pings on the mineral media. I never feed moss or Utrics.

 

[WillyCKH]

Maybe something easy and cute like Kenilworth Ivy? If weedy/ easy plants don't do well, maybe something is off with the media. Have you checked pH & TDS? Would you consider switching to a peat mix?

 

[spiffyzha]

Huh. Okay, mystery solved. It was salt after all. Good call @Lloyd Gordon .

I collected some of the white stuff and dissolved it in water. A lot of it melted straight away, but the grittiness persisted. I attempted to measured the TDS of the solution, but it was off the scale of my cheap TDS meter. I added a lot more water and then the grittiness went away, and the TDS became something high but readable.

At some point I treated a batch of nepenthes media with magnesium, but that couldn't explain why this is affecting (some of) my pings now. It's weird though, it certainly doesn't show up on all of my plants. @WillyCKH must be correct that there's something weird going on with the media.

Anyway, I'm horrified to think I've been watering my plants with (in effect) off-the-scales salty water, but at least I can approach troubleshooting in a less stupid way now.

 

[DevonNS]

Huh. Okay, mystery solved. It was salt after all. Good call @Lloyd Gordon .

I collected some of the white stuff and dissolved it in water. A lot of it melted straight away, but the grittiness persisted. I attempted to measured the TDS of the solution, but it was off the scale of my cheap TDS meter. I added a lot more water and then the grittiness went away, and the TDS became something high but readable.

At some point I treated a batch of nepenthes media with magnesium, but that couldn't explain why this is affecting (some of) my pings now. It's weird though, it certainly doesn't show up on all of my plants. @WillyCKH must be correct that there's something weird going on with the media.

Anyway, I'm horrified to think I've been watering my plants with (in effect) off-the-scales salty water, but at least I can approach troubleshooting in a less stupid way now.

On a side note, it does show how hardy these plants can be..

 

[spiffyzha]

On a side note, it does show how hardy these plants can be..

Right? A few nepenthes, for example, like to live on rocky cliffs near the ocean and get regularly misted with salty ocean water. Makes you think that this whole "minimize the TDS of the water" thing must be a great oversimplification for whatever is actually going on -- eg, maybe they're more tolerant of some salts than others or something.