PC-12 instructor reported finding condition lever in ground idle during recovery from a no flap bounced landing. Instructor was able to engage flight idle; regain aircraft control and perform a go around.

Narrative

Flying with Client for PC-12 recurrent training. We had done all of the airwork and VFR emergencies. We'd done one coupled approach and Client had hand-flown the RNAV XX approach with a circle to (intended) land XY. For training purposes; the circle to land; and intended landing; was flown with the flaps retracted (flaps 0 landing; part of the training curriculum).All was going well; Client had been flying very well and was well ahead of the airplane. On the circle he was ~1200' agl and 130 KIAS; a good speed to do with flaps up.On final we were around 120 KIAS which is a reasonable speed for the flaps up approach.As we got over the runway threshold I felt we were at a reasonable speed and altitude. All was looking good until Client flared well above the runway and the airplane started to slow. I said that we were too high and needed to descend but very quickly speed was bleeding off and we were into the shaker and then got a push which bounced us on the runway. I think what happened is when Client flared I failed to recognize that the pitch attitude was too high for the flaps-up configuration and the speed very quickly deteriorated.As with any bounced student landing I asked Client to add power. I was concerned that Client might put the nose down and put us in a porpoise situation so I took control of the airplane to hold the nose level to slightly up. We were out of runway to salvage a landing and I felt we were in a precarious position with respect to lift; thrust; and drag. Confirming positions of the controls I noticed the Condition Lever at Ground Idle (not sure how it got there but it may have slipped back in the bounce). Somewhat simultaneously I added throttle to full power; moved the condition lever to Flight Idle; brought the gear up (we were eking out a slow climb) and brought flaps to 15 to give us a bit more margin from stall. After just a couple of tense seconds the plane started to climb as in a normal departure and we continued around the pattern and landed normally.In the future; when practicing a flap up landing; I will call for a go-around if a flare occurs too high; or speed gets too low before we are right above the runway. In a flap up landing the airplane should be flown on to the runway with essentially NO FLARE.