The rocks are small, like river rock size, around an inch each. The layer is about an inch and a half to two inches deep.

Spring flowering bulbs are often included in rock, gravel or scree gardens. Usually because these types of gardens offer the very good drainage that these bulbs require as well as full sun. However the 'rock' in these cases is included throughout the soil mix, not just as a top layer or mulch. I would avoid having too thick a rock layer where the bulbs are planted - maybe just a single layer of rock - but the bulbs should be able to grow through a light rock mulch easily.

Bulbs are one of the mainstays of my gravel garden - I have them planted in gritty substrate but also mulch with a 2inch shingle/pebble top dressing.

Thanks everyone!

I noticed today there is a layer of weed cloth between the soil and the rock. How large of an opening should I cut in the cloth? I am planting a bed with tall globe allium in the back, then two varieties of tulips, one taller than the other. I also have some leftover crocus I might add in the front if I have enough room. Do I need to complicate things by cutting bigger holes for the taller growing plants and smaller holes for the smaller plants?

Actually, I'm thinking it would be easier to just pull up all of the cloth in this bed while there are only a couple of plants in there anyway. Better now than in a couple of years when it's driving me crazy.

I think you are right about that weed cloth. You can see other's experience - overall pretty negative.

I second the notion of removing the weed cloth before you do any more planting. It doesn't really stop any weeds (they will seed and freely root on top of the cloth) and is a PITA to deal with with when planting.