As a beekeeper, I'm always interested in how and what I can plant to help my bees. Yet one question that always haunts me is in regards to a summer rain. When a rainfall occurs after a dry spell, how long on average from the time the rain hits the ground does it take for it to work up through the plant and present itself as a fresh source of nectar for the honeybee?
That is an interesting question. Don't really have an answer for that except that I think it depends on what grows in your area.
I expect a dearth during summer months after the spring & early summer blooms. I start progressively planting buckwheat in late May & early June so they will start blooming when the native plants slow up. I do that every week or two right up until winter. Buckwheat starts to struggle right about the time goldenrod & other fall bloomers start blooming. I also have a few hives at an entirely different location (even higher altitude) to take advantage of the sourwood bloom which occurs later in the summer. Some people move hives just for the sourwood honey. Not sure if that is an option for you.
Argue for your limitations and they are yours forever.