Golden Teacher Growing Guide That reputation cuts both ways. Because Golden Teacher is forgiving, beginners often assume it's foolproof, and then can't work out why the tub stalled. It isn't foolproof. It's just quicker to tell you when something's wrong. Here's the timeline, the conditions behind each stage, and the three things that still go wrong. How long does Golden Teacher take to grow? Roughly 6 to 8 weeks from inoculation to first harvest. That's fast for a cubensis —