Zygopetalum, new growth rotting

[MCSchrum]

I've got a Zygopetalum hybrid that has been growing well for the past two years, however, I have had problems with the last three growths. The inner leaves of these growths have rotted before the growth could become a mature pseudobulb. The first of the last three growths rotted before it could produce a flower spike. The second produced a flower spike, then quite growing after the inner leaves rotted. The third and current growth has two flower spikes that are in bloom, but the inner leaves turned brown and mushy and died, leaving only the three outer leaves. I removed these inner leaves and noticed that the rot seemed to be starting from the tip of the leaf and moving towards the base. Also, I noticed that the rotten parts of these leaves were covered in tiny oblong insects (thrips?). I'm not sure whether they caused the rot, or were just taking advantage of the situation. The Zygo is planted in a mix of CHC, sphag, charcoal, and perlite in a plastic pot with lots of vent/drain holes in the bottom and sides. I have a fan on in the room all day, so air movement should not be a problem. It's in an east window under a CFL grow light. Any advice will be appreciated.

[kspalding]

Honestly the only thing I can think of is the weather has changed alot over the years (first a vortex now a heat wave) and your regimen may have to change the same. Try letting it dry out completely first then re-adjust your water schedule.

---------- Post Merged at 11:47 AM ----------

OOh just read about insects this sounds like aphids. They can easily be treated by watered down rubbing alcohol and paper towel (wipe off) and changing out the soil.

---------- Post Merged at 11:48 AM ----------

what color r they.... white aphid, yellow thrip treatment is the same regardless

[MCSchrum]

The insects appear to be grey. They're very small and oblong.

[kspalding]

There are two infesting bugs that fit the description scale and aphid. If thrip they would be yellow (larvae) or black (flying-male or crawling-female). Scales dont actually appear in "bug form" but are covered in shell. Aphids kinda resemble rice but tiny and off color.

---------- Post Merged at 08:07 AM ----------

Aphids are more common when the soil breaks down and goes bad. They also love compost based soil. Scale love young growth and are very prone to the sweetness of orchids. I always considered mealy bugs to be white but some have described them as grey so if they look kinda fuzzy this may be your issue. As I said a quick wash in dish soap and warm water then a diluted rinse in rubbing alcohol and water plus changing out the soil will eliminate all of these problems