Root Rot Question

[RalphJones]

Hi, I decided to repost my question from the Phal Abuse Ends Here thread so more people might be able to see it and help me out.

I have a Phal that I discovered had some moderate root rot once I replanted it. However, the rotted part is often in the middle of the root, and has good solid green root above and below it. I think maybe that when the orchid was last re-potted by someone they broke some of the roots in half and cause rot around the area.

Should I have left the whole root alone like I did? Or should I have cut right above the rotted part and discarded the healthy root below that?

Thanks,
Ralph

[tucker85]

The roots in the center of the pot have a tendancy to rot because that area stays moist longer than the rest of the medium. You can prevent that by letting the medium dry a little longer before watering. A good practice is to place a bamboo skewer into the center of the medium, leave it for ten minutes of so, and then remove it and check for wetness. If it looks moist, wait longer to water. Something else you can do is to place a small net pot up-side-down in the center of the larger pot. That will increase airflow to the center but you'll need to water a little more often.

I alway cut off any dead roots because they will just continue to decompose in the pot. I also often trim an inch or so off the main stem on the bottom. But if you do that you'll be cutting into a large living area of the plant so you'll want to use cinammon or a fungicidal product to treat it. It's not neccessary to cut back the main root unless it's getting too long for the pot.

Here's a picture of the net pot I use in the center of my larger pots.

[Call_Me_Bob]

^^ great information!

[tucker85]

I'm sorry, I missread your question. You were saying that one root is green on the bottom and top but black and soft in the middle. If the end is green I think I would leave the root alone. If the plant has plenty of roots I would cut it off though.

[Orchid126]

When you remove dead roots from the center of the rootball and repot, any medium in the center will stay wet because there are no roots to use the moisture. So don't put medium in the center. Stuff some packing peanuts up there. They won't stay wet. Make sure the peanuts are not the type that disolve in water.

[Bud]

I dont think you have root rot. It might be a root discoloration since there is green that followed up and below...it means the root have recovered and rebuilt itself...I wont worry too much

[Ray]

I have an example photo of what Ralph described in my Semi-Hydroponics presentation - a photo posted here by another grower a long time ago. Here's the sequence of events that can lead to it happening:

1. Plant is potted up in good-quality, fresh medium, and grows nice, healthy roots.
2. Over time, the medium starts to decompose.
3. The original roots - tailored for the fresh medium - cannot handle the deteriorating conditions, so start to slowly fade as the medium does.
4. Meanwhile, new root tissue begins to grow from the ends of the old roots, and as they will tailor themselves to the so-so conditions, they appear to be fine.

Unfortunately, the older parts of the roots will continue to deteriorate, and eventually the connection between the viable root tips and the plant will be broken, leading to a suffering/dying plant.

It is best to cut off the roots and repot, letting new root growth sustain the plant.

---------- Post added at 05:17 PM ---------- Previous post was at 05:12 PM ----------

Concerning "soppiness" in the middle of the root mass, it does not occur because there are no roots to take up the water, it occurs because of poor wicking, and typically is the cause of root loss in the middle.

In a pot, most of the loss of water (evaporation) occurs from the top surface, through pot walls (if clay), or on the pot/medium interface (plastic). Very little occurs in the middle of the mass of medium, and most potting medium ingredients don't transfer moisture very well. This is the primary reason we are taught "not to overpot".

When I pot up a plant in LECA for S/H culture, the medium wicks so uniformly and relatively quickly, that there never is a suffocating, soppy center, so overpotting is not an issue.

[RalphJones]

Thanks for the input.