Re-Potted Phals dying from root rot

[sewcrazy64]

Recently I noticed wrinkling leaves on four Phals I re-potted a month ago. Today I turned them out of their pots and found rotted roots.

As I unpotted each, I noticed that while the top 2/3 of the bark mix was dry, the bottom 1/3 was wet. The were potted in a pre-packaged mix of large bark, perlite, charcoal, and rock chips, and I put packing peanuts in the bottom for drainage. I've been watering them only when I could stick my finger 1 to 1 1/2 inches into the mix and it felt dry.

What am I doing wrong?

[orchidlady]

What was the health of the roots prior to repotting? Were they actively growing? If not, repotting tends to be harder on the plant and existing roots. Were any bad roots trimmed off when the plants were repotted? What are your growing conditions? Temperature? Humidity? Air circulation?

The bottom line is when plants rot, they are staying too wet for too long. This is related to watering frequency, temperature, air circulation, and humidity. The cause can be one or more of these factors as well as the general health of the plant. If you have multiple plants affected that were previously healthy, then the problem is the culture/conditions. Another thing I do with freshly repotted plants is to keep them on the dry side for up to a month. Repotting tends to make the plants more susceptible to rot/disease due to stress and possibly broken/cracked roots.

Susan

[sewcrazy64]

When I bought the plants, they were in soggy sphag. So I re-potted immediately even though the plants weren't actively growing. After trimming damaged roots, there were still healthy roots on each plant. I waited 2 weeks before watering. As I stated, I watered only when mix was dry to a depth of 1 to 1 1/2 inches. The humidity ranges from 38% to 55%. Temp is between 66 - 80. A fan runs 24/7.

I understand the roots rotted because they were staying wet. My problem is trying to understand why the mix is staying wet in the bottom of the pot when the top 2/3 of mix is very dry. Is this possibly an indication that the pot is too large? Everything I've read said to use a pot that would accommodate one to two years growth. I don't know how much growth that is, so I used 3" pots so the roots just touched the sides but were not crowded.

I will appreciate any suggestions.

Dana

[orchidlady]

It doesn't sound like 3' potts would be overpotting, but it is possible that the volume of medium to roots/air circulation was too high. There weren't enough roots to take up moisture and/or not enough air to dry it out fast enough. Sometimes, especially with Phals, the center of the plant doesn't have a lot of root growth present and there is a large open space left that can result in a lot of medium that doesn't dry out as well in the center. This can also happen in the bottom of the pot if there are not a lot of roots and perhaps not a lot of air circulation. Sometimes, if I'm concerned this might happen, I will layer a couple layers of medium and styrofoam packing peanuts in order to decrease the tendency to hold water. Another thing that can be done is use Air Cone pots that have a projection of the bottom up the center with additional drainage holes. These pots are good at increasing drainage and air flow to the center of the plant.

Many people treat the roots on plants with root trouble and in danger of rotting with hydrogen peroxide or even Listerine to hopefully stop any further rotting before the plants are repotted.

There is also a method of checking medium dampness by inserting a wooden skewer into the medium, leaving it there for about 10 minutes, and then removing it and checking for dampness on the skewer. This can help check for wet medium at the bottom of the pot.

Often it takes some experimentation to determine what works best for our own growing situation. That's part of the fun, but all of us have had frustrations, setbacks, and even lost a few plants along the way.

Susan

[EMos]

Dear Dana, I think Susan has given you a lot of good advise, but I will suggest that you post some pictures of plant and medium if possible, cause there might be something else that's escaping us at the moment. And with phals as with many other orchids there are always some rescue tricks

[bedt]

Hi Dana, Susans' advise is absolutely sound, especially the suggested use of a skewer or a wooden support stick, you can push it right through to the bottom. Using this method has saved countless cats of mine. Wish you all the best!

[Brutal_Dreamer]

Yes, good info above!! Post up a photo if possible for additional thoughts.

Cheers,
BD

[sewcrazy64]

Thank you all for your helpful advice! Sorry I'm so long in replying & posting pictures. I had to wait for my hubby to help me upload the pictures.

These are the plants that had rotted roots only a month after repotting. I immediately treated roots with peroxide and placed in bags with a moist paper towel (not touching plant). Is here anything else I can do for them?

This one lost all roots. I have no hope for it really.


This one has started growing fuzzy mold.


Hoping this one has a chance. Should I keep it in the bag or pot it?


This is the potting mix they were in. I think the quality of the bark is poor. When I soaked it before potting, a lot of the pieces fell to the bottom of the bucket, soft and rotted. There is also a lot of pieces of wood mixed with the bark.


Here is a plant I'm concerned may be having the same problem. Again, it was repotted a month ago in the same mix as the other plants. This one is in a 6 inch pot because it's a bigger plant and had more roots.


As you can see, the bottom 1/2 of the mix is wet. Notice the condensation on the inside of the pot. It's been about 12 days since last watered. You can see some of the once green roots are turning brown.


(I really don't want to lose this one; he's my favorite.)


I'm thinking I should repot this plant again. I now have coconut husk chips and lava rock I can add to the bark mix, hopefully improving the drainage. And maybe I should use a smaller pot. Please tell me if this is what I should do. I will appreciate all your suggestions.

[cindiras]

Do you have any styrofoam packing peanuts? Mound them in the bottom of the pot. Kinda like you are making an upside down cone in the pot. Add some damp bark pieces around the styrofoam, spread the phals root(s) down the sides of the cone and fill around them with more damp bark or coconut coir. The mound of packing peanuts provides a dry core for the pot, reducing chances of rot. Doesn't eliminate rot, but makes it less of a problem. Now, the phal with absolutely no roots... Read up on the water culture threads. I think that may be your best try to resucitate it. Basically a clear glass container about half full of water with the orchid suspended in the glass with the base where the roots will grow in the water.

[EMos]

Thanks for posting the pictures, it definitely gives a better idea of what's happening.
Well...all the above advices are good, but I'll just add these notes based on the pictures and growing conditions, and hope that they help you to understand what was the cause or/and rectify:
1. I believe potting mixture was of poor quality as you mentioned, they might not have been treated and contain traces of resin which is unhealthy for roots. the size of the mix is also too varied, they should contain mostly coarse bits, to allow air circulation and appropriate for thick roots. I recommend you use 1/3 charcoal, 1/3 lava rock, and 1/3 pine bark of appropriate size and the styrofoam peanuts as Cindi mentioned at the bottom of the pots. you can sprinkle some sphag on the top around the plant.
2. The 6 inch pot is too big, use a 4 inch or even 3 inch depending on plant size instead
3. Fan running 24/7? In my opinion that's the main reason for the mix drying on the top layer, and remaining wet at the bottom. Roots are not actually taking the water, but it's lost by evaporation. Running a fan a few hours just after watering is a good idea, but doesn't necessarily need to be used all the time.
4. Treat your plants with a fungicide and re-pot as recommended, only for the one with no roots and dehydrated you can use the hydro technique mentioned above.

I think your cultural regime is good and you were doing the right thing, but it's mostly the potting that wasn't proper, and probably the dry air. Placing the pots on a layer of pebbles with water at the bottom is good to increase humidity around the plant that may stimulate the roots, but this doesn't mean giving a lot of water to the plants themselves, as you should be very cautious with the watering at this stage.

To end on a good note the flower is really beautiful, and it's worth saving.

Good Luck