Upside down turf - good for drainage?

E17Beginner

I’ve just had a raised sleeper-bed border put in, about 6 inches high. I’ve noticed the landscaper put upside down turf at the base (so at ground level) and I don’t know whether that’s going to be good for growing or not. 
Part of the reason I wanted a raised border is because it’s clay soil and my first attempt at planting shrubs and bushes was unsucessful because they became water-logged (i’m told). 
Should I keep the upside down turf?
Thank you - total beginner here. 

raisingirl

Yes, I would. As long as it's fairly well buried, it'll compost down quickly and make nice crumbly good soil. Forms an excellent base for your raised bed soil - your man knows what he's doing, I'd say