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how do you kill fungal tartar-like residue on peat?

how do i kill fungus that grows on peat? i bought a bale of peat moss at my local hardware store. I noticed that whenever the peat is moist everything is fine but as soon as the peat dries a yellow tartar-like residue grows on the surface, specifically it likes to grow on the rim of the pot. This only happens when the peat goes dry. If it maintain it wet it stops growing. Does anyone know how to kill it? is it even possible?
Sounds to me like you are describing mineral salts buildup that is most conspicuous when the media surface dries. This is why it's worthwhile washing your peat before use, and be sure to use a clean water source. Of course, without a photo, only speculating.
There are also yellowish-colored algae, but from the description it's impossible to get anywhere close to an ID. I also would like a photo.
here' s a pic
Looks like Whimgrinder is right--that appears to be mineral buildup... little salt crystals left when the water evaporates. How long is it taking for that to occur? You should check that your water is clean, make sure whatever media you bought has no added fertilizer, possibly even give it a good rinse as was suggested. If you can determine water and soil are both clean, then do a repot if it's a CP. Ordinary plants can handle a bit of that buildup but not CPs. I would have to fertilize really high to get that kind of salt accumulation.
Those are mineral salts building up a crust on the soil and it will become toxic to your CPs. Either the soil itself is the source (should have been washed before use) or your water source has too much mineral content. If your container is NOT equipped with a drain hole (I suspect it isn't) then you may need to unpot the whole thing and redo it with properly washed soil ingredients and find yourself a clean source of water. (Its possible that your peat was OK, and that the salts have been introduced via tap water; KNOW your tap water quality before using it! IE: test it.)
I have a problem with this as well. I purchased a potted Drosera regia, and the salts started to appear after I used Osmocote pellets and top-watered the plant. I'm pretty sure my water doesn't have problems because I have watered Sarracenia, Drosera, and Utricularia for months without any problems.

I know the best thing to do in this case is to probably repot, but I'm worried about disturbing the roots of Drosera regia since I've heard that it doesn't take kindly to it, like Drosophyllum.
Osmocote is not appropriate for use on Drosera anyway; discontinue and leach the minerals out of the soil ASAP.
  • #10
I was only following the guide here, which recommends Osmocote for regia: http://www.carnivorousplants.org/howto/GrowingGuides/D_regia.php. Any advice on how to go about repotting it with minimal disturbance to the roots?

Wow. If John Brittnacher recommends Osmocote then I am mistaken. However, you did note that he says he uses only four to six pellets per pot, per year, right? If you're seeing salt accumulations on the soil, either you've applied too many pellets, or the soil was contaminated with minerals from the start. Assuming that your pot has drainage holes (it should) then you can gradually leach the minerals out with copious amounts of water when you normally do water (IE: lots of water poured through the pot, between normally scheduled waterings.)
  • #11
Ok thanks! I haven't really been watering the plant much because I heard that regia doesn't need a lot of water but I'll try to flush out the minerals by watering it more and letting the water drain out through the drainage hole. I think the soil might have been contaminated from the start.
  • #12
I recommend staying away from osmocote in general. Just use a weak orchid fertilizer that you can dilute yourself. There are always defective pellets in the bottle that will release in just a matter of days, instead of slowly over a few weeks like they should. Trust me, I've used them a lot (and on regia)!
  • #13
so are you guys sure this is mineral buildup? I never use any hardwater on the soil only pure drinking water.??? Ill experiement and see. It really looked like a fungus to me though.
  • #14
By "drinking water" do you mean distilled or reverse osmosis? Or do you just mean bottled water or spring water. Because regular bottled water still has too high a mineral content for CPs. The minerals make it taste good. You need distilled or reverse osmosis water for the long term.
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  • #15
Or rainwater, or in my case, tap (only if your area has low mineral content).
  • #16
i think its reverse osmosis. The one where you go to the water store with the big tank and they fill it for you. 25 cents a gallon. Ive always used it for all my plants never have problems but the build up (which i think is fungus) is annoying and looks ugly and im also just worried if i use it my plants will get contaminated with this yellow fungus but then again i have the bag of peat sitting there very tempting to use.
  • #17
Its not fungus, its mineral deposits.
No, it may not have come from your water source, it may have been in the soil ingredients you used. As I explained, Peat can often have some mineral content and it should be washed before using it for CPs. I learned this myself a few years ago by using Peat straight from the bale, and I got mineral deposits just like your photo depicts, within a week of setting up a bog pot. If your water supply is clean (based on your statement about source, it likely is) then the minerals came from the soil components.
  • #18
alrighty thanks! im glad its nothing contagious, a thorough washing should do then :-D