Mold or mealybugs on phal? Sequence of problems with new orchid - Orchid Board

thegirlwiththemouseyhair · #1 08-06-2018, 11:31 AM

I've been struggling with a new-ish orchid that I bought in June. I inspected it carefully in the store and didn't think there were any major issues like pests, although it looked a bit dry. I repotted it when I bought it, put it in Fafard medium (medium-size fir bark and coconut husks; excellent for my other orchid which I've had for two years), and then saw some white stuff that looked like mold growing on the bark a few days later. I tried putting the orchid in a new medium. Since I couldn't find more Fafard medium at that time, I tried the orchid in Miracle-Gro (large chunks of bark, charcoal, and perlite). After several weeks in the Miracle-Gro, I was struggling with the watering schedule and found the orchid looked really dry and was losing bottom leaves. I found some of my preferred Fafard medium and repotted the orchid this past Saturday. Some of the roots had a bit of root rot, but the plant has still got lots of roots left, so I figured I could save it in a medium that I know has worked with once a week watering.

Unfortunately, this morning (Monday) I noticed white stuff growing on the bark and some of the roots and stem. I'm not sure if it's pests like mealybugs, or snow mold, or something, and I don't know what to do. Should I give up on this orchid and look for another one? It's really frustrating that I've kept one phal going for two years, but can't seem to repeat that with any new additions. Sorry the pictures are not the best; any advice is much appreciated.

aliceinwl · #2 08-06-2018, 11:58 PM

My guess would be mold. For me, meally bugs tend to show up in the most succulent parts of the plant. I’d do a careful inspection inside the inner groove of the top leaf where it joins the crown and around the bases and stem attachment points of any green leaves. If it is meally bugs, they should be in these spots too.

If it’s mold, I’d chalk it up to the media breaking in and dead material on the plant decaying and not be overly concerned.

thegirlwiththemouseyhair · #3 08-07-2018, 08:29 PM

Thanks a lot for the reply. I'll do a better inspection of the leaves (of which it lost several) tomorrow, but I think the fuzzy mold-looking stuff is just on some roots and some of the medium. Isn't there a risk mold will choke the roots, though? Is there anything to do about it?

aliceinwl · #4 08-07-2018, 11:51 PM

Mold doesn't usually become a problem unless your media is too old or you are keeping things too wet.

If it's been over a year since re-potting, repotting into new media would be the best option.

If your media is newer than this, it should be pretty much drying out within 7 days. You should wait until the roots look silver to water again. People have had mixed results with the skewer method in the sticky at the top of the forum, but it really helped me to gauge when to water so I think it's worth a try. I still use it on Phals that I over potted or that I can't see any roots through the container.

If your orchid is having some root die off, the dead tissue will tend to mold when things are moist after you water. In these cases, the mold dies back as the pot dries out again, and the next time you water there's less tissue and less mold, until the problem solves itself.

Before I started mixing my own orchiata, perlite, and charcoal media, I bought some packaged media by Better Grow that looked really good: fir bark, perlite, charcoal, coconut chunks, no dust. For whatever reason, the Phals I put in it suffered near complete root death. I didn't see recovery after re-potting until they were able to start pushing new roots. It might take yours awhile to recover now that the growing conditions have improved. My house is pretty dry so I don't have issues with water sitting in the crown and I found misting the root buds on the stems of those Phals really seemed to spur generation of new roots.