Feeding the Honey Bee's

I had a Hummingbird feeder still out and it was attracting bees like crazy. I noticed a late Hummingbird come to feed last week (November 10th). I only saw him once. He appeared healthy. I guess he just got a later start migrating south. They normally leave this part of south Georgia the first week in October. I quickly made fresh syrup (4 parts water to one part sugar, heat to boiling, and cool before filling feeder). The bees were thick on the old feeder so I left it there for them. We decided that they needed to eat too and since there are not many flowers for them to go to, I put a flat plastic lid down on the ground and poured Hummingbird syrup on it. The bees loved it. There must have been 50 bees hanging around. They were not aggressive and I never got stung. I refilled it for several days until I ran out of the mix. I was too lazy to make the regular boiling hummingbird syrup so I just eyeballed it, mixing some sugar and water, stirred it and put it out for the bees, without boiling it. A few days later, I noticed about 10-12 bees laying dead around the feeder, and the other bees were gone. I don't know if I put too much sugar in it or what, but I felt bad. They weren't hurting anything and are very helpful in the garden. I plan to make some more regular nectar for them today. I will use the boiling water and 4/1 water sugar ratio.