How do you determine the exact point at which a hive should be put on the heather ? You, clearly, have the knowledge to get it just right as your experience this year is, by your estimation, above average. The actual date is obviously influenced by where in the country the heather is and presumably the local climatic conditions ... so is there an indicator ?
lol....were it that clever I would have something worthwhile to tell, but alas I do not.
We actually start our season from earliest spring with a goal of maximum number of colonies in the correct condition for going to the heather, which accounts for approx. 80% of our cash earnings. Thus the various blossom harvests are more of a by product rather than a target in themselves. This results in us having very poor early season harvests, but the biggest heather crop in the country most years.
We watch the BELL heather to get a firm handle on when to start the big move, which usually means a start between the 3rd and 8th of July, with a target in all but the very latest of seasons of finishing on the Ling only sites by a date between the 25th and 30th of July. This year we were seeing a later than normal Ling opening (it did catch up though) so completed on 3rd August.
Thus we run on a Bell heather trigger for starting, and then just go at it full tilt for around 3 weeks. This normally means our arrival at the Ling is timed for the very latest lots to be there at 5 to 10% flowering stage. So its a rather mechanical process, and if the big flow is in the 3rd week of July on the Bell then many of our hives will miss it. Thus its really a sort of educated luck.
Back to the subject of lore. There is ample documented advice that if you have the bees up for the heather by the grouse shooting starting, so 12th Aug except when that falls on a Sunday, then you are up in time. This is seriously outdated advice, also based on a seriously outdated production system (cramping), yet is still widely promulgated.
In the last 20 years if you went up for that date then in about one third of seasons you have missed the best, and sometimes missed it all. In OUR three main areas it is best to be on the moors by the last week of July.
Not going raking about looking for it, but there are Norwegian studies about yield potential of Calluna related to weather patterns in the few months preceding flowering sate, and there is a cumulative effect of sunshine hours on the foliage influencing the nectar potential of the bloom. Of course we also need water, preferably in abundance, to trigger a major nectar flow. This year the moors got a bit fried in the heatwave which did a lot of damage, but once the rains came the nectar flow was heavy, however overall ground water was sparse, and once nature stopped replenishing the available moisture the flow tailed off. Thus there was not a huge amount to be had late in the process and many of our colonies went into 'fill in down' mode earlier than expected.
Upside this year is that the bees look in great condition for winter, with abundant young bees, plenty brood still hatching, and low varroa levels. Young queens effectively and abundantly mated too, so expecting a good wintering performance. A stark contrast to the run of iffy to awful summers we just had in Scotland and the poor autumn condition of the colonies and the bad winter losses flowing from that. All we needed was a decent summer to lay several of the current 'bogeymen of choice' to rest.
