>>29151
First, it wont need ericaceous compost. Second, bulb sets prefer a firm soil or at the very least don't mind. It might be a drainage issue, try adding sand, but not beach sand as it's full of salt. Try concreting sand (not actual concrete mix full of stone, just the sand) or any washed sand.
Planting in the autumn will give them more time to grow for bigger bulbs.