Hi
I am sort of new to orchid keeping and even have a little trouble navigating this forum, so please forgive any mistakes I make. Please also forgive the book I'm about to write. I'm a wordy person and always feel it's best to give all the information I can when looking for informed advice.
After seeing the plant in bloom at a great local nursery, (RF Orchids), AND doing my research... I purchased a Prosthechea cochleata about 2 months ago. It had 5 pseudobulbs and the dried up and trimmed remains of two flower spikes. I had seen the plant blooming on previous visits to the nursery and I feel it was healthy upon bringing it home. Thought this one would be easy given that she is a species which grows in my own environment of South Florida.
As is my usual, I kept the plant away from my small collection and in the pot it came in for about 4 weeks. It was in a hanging cone-shaped pot and I needed it to sit on a shelf, so while the plant itself didn't need a repot, I needed to repot it so I could provide proper care. At this time, I discovered that most of the interior roots were dead.
I trimmed all of that away, leaving just a few roots that seemed the most healthy... though none of those roots displayed growing root tips. Sadly, at least part the root death must have happened during her first few weeks with me because I did see a growing root tip or two upon purchase... though the majority of the dead roots were deep within and some may have been dead from the start. I cannot figure out why root loss may have happened as I treated her to the best of my ability based on advice from the nursery and my own research.
Upon repotting, just like my excellent local nursery, I used hydro balls and charcoal as potting medium, and (as is also my usual go to with new or young plants), I put sphag as a top layer with the intention of promoting growth on young roots as well as promoting new root growth.
The plant lives outside, getting indirect light on a screen porch. I have not measured the light but this plant gets the same lighting as a couple of encyclias and brattonias that do well in that area. They get morning sun through the screen and are shaded before noon.
The plant is watered every 2-3 days dependant on the medium's dryness... In other words, she is not watered until the medium goes very dry. The pot is soaked in a very low dosed fertilized solution at each watering and the pot is flushed with plain water once every two weeks to reduce the chances of salt build up.
I fear that I have caused the rot either from overwatering, (seems unlikely since the pot gets very dry between waterings), or from the soak method of watering. Soaking, of course, hydrates the roots, the pot, and the potting medium. Upon removal from a 15-20 minute soak, the pot (clay and full of holes) drains quickly due to the chunky medium, and the medium and pot dry quickly as well. It's the sphag top dress that maintains a little extra moisture and humidity near the base of pbulbs between waterings.
A couple of days ago, one of the largest growths was flopped over sideways.
It was then that I discovered that the base of this pseudobulb and one other dislplayed rot. The leaves and the rest of the bulb looked fine and the rot only reached a couple of centimeters up from the very base. I worry that the rhizome, (which I cannot really see) is rotting.
Also recently noticed and perhaps noteworthy... tiny white jumping bugs on this plant. I cannot be sure, but I believe they are springtails, as they look a lot like the springtails that I culture and keep for terrarium use. It seems unlikely that these insects are the problem, but again, just trying to give all the info. Are there detrimental insects that plague orchids in a tropical environment, which also resemble springtails in both how they look and how they move?
Upon unpotting her this morning, with the intention of using a sterlized cutting tool to remove these two growths... which was pretty sad given that other than at the very bottom, these growths appear plump, green, and healthy.
Well, a tool was not needed. When gently seperating the pbulbs to try to get a look at what's going on below the rot... these two sick growths pulled off of the plant very easily. Now, I'm even more worried about what's going on below the visible rot. Does it sound as though the rhizome is suffering rot? Idk but I really thought things were going well with this plant since she started a new growth a couple of weeks ago.
Based on good advice, my plan was to remove the rotted pbulbs, then treat the plant with Captan Fungicide and afterward, to apply cinnamon to open wounds, (which I also cannot see.) This is still the plan for later today, (when I'll have a babysitter since I prefer not to do this kinda stuff when I may need to give quick attention to the kiddos.) In the meantime, I am hoping for all the good advice I can get.
My goals are simply to save the plant, including the newest, tiny growth which seems about the only good thing to have come from my care. My questions are...
How would you treat this?
I am afraid that the plant has only one halfway decent root... I know that moisture is the best friend of rot, so don't want to keep her wet but...
After rot treatment, how to best promote new root growth and keep that tiny new growth in good shape moving forward?
In the last year, I've done pretty darn good with Phals, Dens, Catts, Encyclias and Bratts, with a small collection totalling about 30 plants. I love them all very much, but the Prosthechea cochleata is one of my very favorites, if only because she is a local girl and I would very much like to see those jellyfish blooms occur under my care. Please help!
Lastly... I am trying to include photos in this post, but so far, have only had success in uploading them to my gallery. Please have a look if you have the time.
Thank you!!!!