Question: Degarmoara Shibumi 'Purple Rain'
 

I picked up a Degarmoara Shibumi 'Purple Rain' at the Santa Ana Zoo orchid show in September. It's in bloom, beautiful, and I can provide the conditions it likes long term. It has 4 large pseudobulbs and one older tiny one, all feel firm with minimal wrinkles.

It's in a 6-inch pot and looks to be growing in small bark that has broken down considerably. The bark on top looks good, but an inch down looks like compost. The pot gets significantly heavier after watering and stays wet/damp for longer than I would expect if the bark was still in serviceable condition.

I know it's best to repot these types when a new growth is about to put out roots but since there is no new growth in sight, is it better to leave it in broken-down medium and baby it over the winter or carefully repot it out of season?

I suppose the answer to your question lies, to a significant degree, on how much effort you want to expend, and when.

Living where you do, I doubt the seasonal variation is much of an obstacle, so it will probably stay actively growing.

Repot now, and you may risk some flower life, but your overall level of care will be more-or-less "normal", whatever that may be. Wait, and you have to baby it for a while, but may extend the flower life.

Personally, I'd enjoy the blossoms while they last, babying it in the mean time, then repot, whether it's truly ready or not.

That’s pretty much what my plan was, thank you for the confirmation that it’s a good option.

Yes, we have relatively long winter days and so long as the morning fog/cloud cover burns off, we have very sunny and warm winters. My indoor plants continue to grow for almost the entire year, only slowing a bit in Jan-Feb when we typically have extended cloudy weather.

I don't recall whether you grow in the house or a greenhouse. I have somewhat warmer winters than yours because I grow in a sunroom. I wouldn't repot an Oncidium at the wrong time just because of old medium. I would nurse it along until it grows again. If your growing area is fairly warm that will be before long.

Indoors, next to a partially obstructed east window and in front of two large unobstructed south windows with sheer curtains. The next 2-months will still be warm.

Dec-March if it’s sunny the daytime high where the plants are will be 74-78F. Cloudy and the high will be 70-73F. Lows not below 63F, usually higher. Humidity is managed with a humidifier.

At the moment it’s sitting on my kitchen table to enjoy the blooms, it’s in the same room just lower light. The Phal. next to it is growing a leaf so it’s not in total darkness.

My only worry is I’m not familiar with the decline patterns of this alliance and the pot is opaque so no help there. Checking the roots of new plants is always a must-do but this one seems like it would not go well once I flip the pot over. Not having a known baseline is frustrating.

Treat it like sphagnum moss. Let it get near dry, then just run a little water over the top - don't soak the pot when you water.

Update: I've discovered there are some small grubs in the pot. I haven't noticed any adult creatures emerging from the mix, so I can't ID them. I know it is possible that the grubs are feeding on the broken-down bark, but they could be eating the roots too.

Would this discovery change any of the aforementioned recommendations? All of the flowers have fallen and I do not yet see any new growths.

They're probably eating the plant. I would unpot and shake off old medium. I'd dunk the bare root plant under water for 4-6 hours to drown beasties, and repot.

Thanks. That’ll be on tap for tomorrow.

The visible bark it’s in looks to be very small, about 1/8-1/4”. Would a mix of small to medium Kiwi bark be suitable? I can sift it to collect everything 1/4” and below if it needs small bark. I also have some very small seedling sized bark but I fear it would be too densely packed in a larger pot.

It depends on how often you can water and how fast it dries out there. It needs air at the roots, but it shouldn't dry out.