All 89 bee plants
Teasel pollen
Dipsacus fullonum
Pale lavender, faintly pinkish, in the blue / purple range.
FloweringJuly to August
PollenGood
NectarGood
SeasonSummer
WhereWaste and verge, Hedgerow, Garden
Worked keenly in high summer, and the pale mauve loads are hard to mistake.

Easy to mistake for these
Closest pollen colours in our set, measured the same way the pollen identifier scores a match. Colour alone will not settle it, so check the flowering months and what is actually growing near your hives.
Confused with in the field
Noted by name in our own records, rather than worked out from the colour.
Out at about the same time
Saw a load like this going in?
Sample the colour against all 89 plants, then keep a forage record per hive.