EU 0.8 mS/cm threshold separates blossom (≤) from honeydew (≥) honey. Conductivity tracks mineral & ash content — and correlates with color and antioxidant load.
BlossomNear thresholdHoneydew / exception
Acacia
0.16
blossom
Clover
0.22
blossom
Sage
0.29
blossom
Lavender
0.32
blossom
Orange Blossom
0.35
blossom
Tupelo
0.39
blossom
Blueberry
0.41
blossom
Sourwood
0.45
blossom
Linden
0.53
blossom
Wildflower
0.54
blossom
Manuka
0.60
blossom
Eucalyptus
0.60
blossom
Avocado
0.70
Near EU
Buckwheat
0.75
Near EU
Heather
0.77
Near EU
Chestnut
1.15
honeydew
0.00.8 EU limit1.5 mS/cm
Chestnut exception: EU Directive 2001/110/EC lists chestnut honey as an explicit exception — botanically a blossom honey, yet its conductivity (0.90–1.40 mS/cm) exceeds the 0.8 mS/cm honeydew threshold. It may still be labelled as blossom honey in EU member states.
Sources: Bogdanov et al. (2004) Mitt. Lebensm. Hyg. 95:57–75; EU 2001/110/EC; White (1975). Values are representative midpoints; individual jars vary ±0.1–0.2 mS/cm.