How long until spikes grow?
 

A friend gave me her orchid before she left the country. After it bloomed and the spike turned brown she cut it off at the bottom, which was over a year ago, and it has never grown back. The leaves seem healthy (if not a bit dark) and I only water when it dries out. Am I doing something wrong, or will it grow back eventually? After she cut the spike off she took it to a gardener who told her she shouldn't have cut it off, but of course it was too late. Help!

I'm not sure what kind it is...

Hi, welcome to OB! :)
Since you don't know what kind it is, could you post a picture for us? Whatever the orchid is, if the spike was brown, then the gardener was wrong. Dead brown spikes won' do anything more, they should be removed. Once we know what your orchid is, we can help you better!

There are three common reasons an orchid won't bloom - in general order of likelihood:

1. Insufficient light
2. Insufficient nutrition
3. 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.