Phals with rotting roots - nearly always

[Abby]

Hi,
I'm a new member. I've had orchids for about 2 years with some luck but not much. Mostly I have trouble with root rot apparently from overwatering. My orchids are in a huge sunny southwest facing window. Now that its winter and the heat has been on I've put a humidifier in the room. The rh is approx. 50%. Anyway, when I buy an orchid, usually a phal or paph or oncidium, I buy it when it's just about to bloom - I have it while it's in bloom and it's healthy and then once it's done blooming, I repot it in a tight clay pot with the proper orchid bark. I usually fertilize every other week and water thoroughly once per week. It seems like I'm following all the proper directions but I'm constantly having trouble with root rot. Right now I have several Phals that I repotted about 2 months ago - applied fungicide - and now their leaves are dark green, limp and wrinkly and they are not growing. This happens way too much. What am I doing wrong?

[Mrobert]

I'm sure more experienced members will chime in with some helpful hits, but to be brief and timely I will chime in with:
It is not necessarily required to report after the plant drop its blooms. The medium the orchid came was likely the medium the orchid grew its blooms in, so it's probably OK to keep the orchid that medium unless it looks very deteriorated.
It sounds like you may be potting your orchids too tightly. A tight potting keeps air from penetrating down into the center of the medium and without air there is no evaporation and good conditions for root rot. A tight potting is going to dry out on the surface while remaining soggy in the center. A good way to test if the center is damp is to wiggle a wooden skewer a few inches below the surface. If you pull it out and it is damp you probably don't need to water.
-MR

[Mehera]

Hi Abby,

It does sound like you're doing most things right. You say you buy a plant that is ready to bloom, and enjoy the flowers--repotting when they are done. What I'm thinking is that the plants are coming to your house with subpar roots, and after several weeks or more of blooming, might be getting in bad shape.

Lots of people repot a plant as soon as they bring it home so they will know of root problems early on. And you do lose some flowers this way. At the least, I would let your plants go longer before watering again. Stick your finger down into the media and see how moist it is before assuming that it is time to water.

[Abby]

Thanks for the advice. I think the nursery I'm buying my orchids from may be giving me bad advice... I was told to jam the orchids roots very tightly. The bark is so packed I can hardly stick anything in it to test for moisture. I will try loosening them up a bit. Also, I find that spagnum moss keeps the roots wayyy too wet so I always repot after blooming because I don't trust the spagnum - maybe I'm going overboard but the spagnum stays wet for weeks... do you keep phals in spagnum or bark? Thanks again.

[Abby]

Hi Lynda,
Aha, I never thought to check the roots right after bringing the orchid home - that's what I'll do next time. I'll bet the nursery buys in bulk from 'who knows where' and perhaps they are only in good condition temporarily. Thanks for the idea!

[Mehera]

Lots of phals come in sphag, and it is true that if it is starting to degrade it can hold moisture for weeks. I usually repot plants like this pretty soon after getting them because I find that the roots have often started to rot before I take them home.

And remember that the roots of these orchids love to get air around them--being tightly packed in a sodden media is a death sentence.

[Abby]

one last question ~ how long does it normally take a phal with rotted roots to recover. I removed all the rotted roots but they seem to be languishing for months now.

[hcubed]

It can take quite a while depending on how many roots it was left with! I would say you can still water even less in the winter. I water about once a week in the summer and once every two weeks or less in the winter - totally depends on the pot and the plant. MY humidity is around 60% in one location and 46% in the other. I don't use any humidifiers. What it is the humidity like without it? I know New England winters can be dry, but my plants have no problem with above 40% so I think I wouldn't use the humidifier until it got a lot drier. What is worse than wet is COLD and wet.

I have a phal I have been waiting on since the summer, but it had a serious root problem.

[Abby]

I'm about to leave for a few days - Thanksgiving - so I'll keep the humidifier off. It has been rather cold and damp in my orchid room - approx. 60 degrees with almost 60% humidity. Is that bad or OK? I'd have to get a space heater to keep the room above 62-63 in the winter - the heat sources are in the adjacent rooms.

[hcubed]

I don't consider myself an expert on this by any means, but I think I would just keep the plants a bit drier if they are cool like that. I'm sure they wouldn't mind being a bit warmer but I doubt the cold alone will kill them. I think mine get done to 61 or so at night, but a bit warmer in the day. 64 right now.