Oil Seed Rape (OSR) Honey

Oil seed rape brassica napus has become increasingly common in Pembrokeshire.  Bees love it and will take themselves to a field 3 miles away in preference to closer forage.  But the honey produced can be a problem for the beekeeper who isn’t aware of its properties, the main one being to granulate rapidly in the comb making it impossible to extract.  To find out more I spoke to Geoff Bazin, who as a former Essex beekeeper had plenty of experience with OSR and provided the following advice.

“Be prepared to extract the honey from OSR as soon as the nectar flow from it has stopped, when the flowers are dropping.  The bees may become more aggressive with the loss to them of this source.  Extraction should take place before the cells have been sealed.  Test the ripeness of the honey by shaking in a downward movement with the comb face down over the hive.  If very little nectar is shaken out the honey should then be extracted as soon as possible.  The honey will granulate if the supers are left in a shed for a couple of days for example.”

[Editors note: Once extracted the honey can be stored in honey buckets but will become viscous and will not pour.  But the honey can be returned to a runny state state by stirring it using a clean paint mixing paddle run at low speed in a power drill.]

“If OSR honey has granulated in the comb it cannot be extracted.  If this happens you have two options:

  1. To recover the wax and honey – Cut out the comb and melt it down in a container over boiling water – wax being of course flammable.  The honey and wax will separate when cooled.  The honey is second grade having been heated and is only suitable for cooking (not a bad thing!). The frames can be boiled to clean them.
  2. To reuse the comb but lose the honey – Score the surface of the cells so the honey is visible.  The metal uncapping fork is the best tool for this. Soak the frames in water for a few days.  Ideally starting at hand heat.  Agitate the frames from time to time until the honey has dissolved.  The water with the dissolved honey is then discarded.  The frames can be put back in the hive for the bees to clean up and use.  Granulation can occur if honey is stored in the frames as a result of residues of the OSR crystals in the cells.”
Thanks to Geoff for this advice.
Additional information from Ian Richards, added 9 June 2012
Before returning supers to the hives soak them in water to remove OSR honey still in the comb.  Otherwise the OSR remaining will cause any subsequent crop to granulate.