when to put clone tray under light?

I took clones 4 days a go in rock wool cubes. They have been sitting in a humidity dome in the corner of my veg room, no direct light on the clone trays. I just checked on them and they are looking great, the cubes are still wet. So when do I need to put the trays under a CFL? None of the roots have popped out of the bottom of the cube yet.

Wouldn't hurt to put them under lights now. Will they still be under the hood? depending how big the cubes are it may take a while to see roots coming out. Wouldn't hurt to raise the hood a little by putting something under it to raise it an inch or so and see what happens