Last summer, after 40 years, I finally got to know why fireweed does not always give honey.
Last summer was really hot and period was long. Canola gived very little honey. I had in several points hives.
On sand and cliff areas fireweed suffered lack of water. It gived very few .
At same time on moist clay area fireweed gived measures I ever had seen. During 2 week period honey came in 200 lbs per hive.
My place was like this and area was about 15 hectares and 3 hives in the middle of area. Plants were 2 meters high and in one stem it was 20 flowers open at same time.