I think the major honeybee forage now is dandelion and queen anne's lace. About late June or early July, I planted an area of my garden with buckwheat. I think it was early July. The seeds germinated quickly, and grew rapidly. They are now blooming.
From what I read, the buckwheat is a fantastic bee forage. However, the nectar supply is in the am, so you have to watch then for honeybees. This morning, the flowers were covered with honeybees.
They are still very active on borage and oregano flowers. Next year I'll have to plant a lot more borage and oregano, I think. Also, deer don't eat those. I remembered that in the past, deer ate the buckwheat plants.
I tried growing buckwheat in 2015. I don't remember a lot about it, except it looked about the same, and deer ate it all. This time it's in the fenced garden.
Since buckwheat seems to bloom so quickly from seeds, I planted a second approx 8 foot by 8 foot area with more. I don't have a lot of room. That was the potato area. If I had the ambition, I could clean up another equal or larger area for the same, but there is more firewood to cut.
This photo was in afternoon and using cellphone, so apparently not much nectar. They are all over the neighboring oregano flowers.
As I understand it, the entire buckwheat plant is edible by for fowl, so after it stops blooming, I can feed it to the chickens and ducks. Also, if there is time, we might get "grain", the buckwheat seeds. That's an off-chance. I read that buckwheat mobilizes bound phosphorus in the soil and stores it in the plant, so if it is turned over as "green manure", there is more phosphorus available for future plants. It also crowds out weeds and shades otherwise unused soil. So, it's all good.