Please try and avoid feeding hedgehogs mealworms at all. If a few are put out, there may be other people in the area putting them out also. The hedgehogs will scoff the lot and as ladybirder has correctly said, they end up with bone disease.
Before I knew about this, I used to put out an awful lot of mealworms, as I had 6 or 7 visiting hedgehogs per night, sometimes all at once! The barging and snorting of one gained it the nickname of Bully. In the following 2 years, the number declined suddenly and I'm hoping it wasn't because of the mealworms. Also, if you put mealworms out for birds, especially at this time of year, please soak them in warm water for at least half an hour before putting them out in the garden. If the parent birds take the dried mealworms to their young, they rehydrate in the babies' stomachs thus dehydrating them. If the mealworms have been soaked, the babies are naturally receiving water at the same time, so they remain hydrated. I've only read about this recently myself, on the RSPB website and it makes sense once you know.