Problems with Re-potting Various Types of Orchids - Orchid Board

paphlovian · #1 07-31-2007, 11:29 PM

Hello Orchid Friends!

I repotted my first orchids several weeks ago. The main reason I repotted the first three was because I noticed fungus/mold (a whitish/pinkish growth) at the base of the orchids on the potting medium. (My patio gets zero direct sunlight during the summer, which I think might be contributing to this) With each orchid I've repotted, I feel that I'm doing something wrong...
for example:

1.) the very bottom small leaf on the phalaenopsis is wilting and turning yellow and just tonight I noticed that one new root growth at the base that can be seen over the potting medium that was looking very healthy when I repotted seems to be falling off and has something whitish on it (fungus? mold?). I'm afraid the roots beneath could look the same! I used a generic orchid potting mix by Better Gro and placed some finer schultz bark at the top.

2.) the stalks (is that what they're called?) of the dendrobium I first repotted about a month ago shrivelled up from where they were before and now have yellowish tinges on them. The good part, though, is the new growth on the plant (since I bought it) is still looking alright! I just used the Better Gro mix with these.

3.) the bulbs of another orchid (I bought it without a label and I'm not sure what type it is but the base of the stalks are bulb-like, almost like little onions) that I decided to try separate into multiple plants have shrivelled (though they have stopped after their initial shrivelling, thank goodness). I just used the Better Gro mix with this.

I also repotted three paphiopedilums several days back which are looking okay so far!

There are other orchids I'd like to repot, but don't want to do it until I can feel more confident in my repotting abilities.

I hope someone might have suggestions to help!

Thank you!!!

caseydoll · #2 08-01-2007, 08:36 PM

Angela, hopefully someone who knows more than I about this stuff will chime in but until then I will try and help a little (i hope!). I wouldn't worry about your phal too much. The loss of a lower leaf is normal with them and usually a new leaf will replace it on top. It's when the upper most leaves start dying or yellowing that you start worrying. The root could be shriveling or dying because it's not getting enough moisture maybe? Sometimes when you repot it takes awhile to wet the bark (if that's what the mix mostly contains). Sometimes you have to water a little more for the first couple of weeks or so to make sure your orchids are getting enough water. Try misting the top of the mix everyday for awhile to get the upper roots wet. That has helped my phal that was having a similar problem. The same goes with the shriveled bulbs on your other unknown orchid. If the roots were healthy when you repotted then it just may need a little more water. Did you soak the mix before repotting? I'm just giving you some suggestions on what has worked for me, I could be way off on what your particular problem is. I can't give any advice on your den because I don't have one but I have heard on here that they don't like to be repotted so maybe it has something to do with that. Hopefully this helps you out a little.

Sarah

paphlovian · #3 08-01-2007, 09:42 PM

Thank you for the suggestions, Sarah!
You might be right about the orchids not getting enough water. I have not been soaking the mix; that is something I first read about recently on this forum and realized I should have maybe done that (for the future!). It could all just be a water issue. And for the phalenopsis leaf-- good to know. I just didn't know if the upper root would just shrivel up and if the whiteness on it is abnormal (possibly fungus). It looked great before I tried repotting.
Thanks again! I need to remember to soak my medium before I try to repot next time.

caseydoll · #4 08-01-2007, 10:43 PM

Does the root turn green if you water over it really well? If it does then the white stuff is just the normal film that covers their roots. You notice it more on the roots exposed to air (at least with mine). Its called velamen and it helps to absorb moisure from the air. If it's more fuzzy then it may be a fungus. It depends what it looks like. A lot of people don't soak their mix first because they prefer to work with it dry so thats not a big deal. You just have to really water it well afterwards and maybe every few days depending on your conditions. You don't have to do it forever, just until the mix starts staying slightly more damp. Then you can water normally so nothing gets rotty.

Sarah

paphlovian · #5 08-01-2007, 11:11 PM

I'm familiar with how the whitish roots of the phalenopsis orchids will turn green when you water them. But, the one I was concerned about did not turn green to the same extent (part of it remains white), though this could be because it has shrivelled up a bit. I hope that's why!

Regarding the bulb (or stalk) shrivelling up a bit: is it possible to get them to plump back up to the way they were before?

caseydoll · #6 08-01-2007, 11:27 PM

Yes, they will plump up once they get more water.

Sometimes if they go without water for long periods they will shrink so badly and lose so many roots that they may not go back. But in your case I think that they will go back to normal especially since you said that they had stopped getting worse. I think a little more water will do wonders.

One of my phals has a really white root too that is completely out of the pot. It seems thicker than normal but I just think it's because I hadn't been misting it and it was only getting watered once a week. I've been misting it everyday for about a week now so I guess I will see if that helps. We will both experiment together!

I wouldn't think it's a fungus though since it usually likes to grow on things that are damp.

Sarah

paphlovian · #7 08-02-2007, 12:12 AM

I wonder how different orchids respond in our different climates. I see you're in the northern US. In Florida, the air remains very humid for most of the year. My patio is not getting any direct sunlight this summer and the air remains very humid. I am originally from Minnesota, and I remember it staying much dryer, even through the summer. I might not be suspiscious about it being fungus, but I have repotted several orchids (including the one with the suspiscious white root) because there was fungus (or mold?) forming in the medium at the base of the plant. I grow other plants on my patio and have scrapped off the top layer of dirt for some of them because green mold was growing.

That's good to hear that I can hope for them to plump up with more water!

It would be interesting to try similar "experiments" in different climates (i.e., Florida and northern US) to see how different the outcomes were.