There are three common reasons an orchid won't bloom - in general order of likelihood:
- Insufficient light
- Insufficient nutrition
- Excessive nitrogen
On the assumption that it is a phalaenopsis, there is a 4th possibility, that it is being grown at too stable of a temperature. Most phals grow best if kept very warm, but require a couple of weeks over overall cooler temperatures in order to initiate flower spikes.
You also posted a question about light, so if this is in the east-facing window, that should not be an issue (phals like low light anyway).
If you keep it too dry and/or feed it too little, #2 could be the issue.
Excessive nitrogen gives leaves a bright, emerald-green color, so it's relatively easy to diagnose that.
If all of those appear to be OK, I'd look at the temperature change - something that naturally occurs in the Fall for most of us, leading to winter blooms.
Hybrid Mode
