Until recently, the scientific name of Labrador tea was Ledum groenlandicum. But under a natural, cladistic classification, it belongs within the genus Rhododendron, a large group that also contains the large, showy shrubs commonly referred to as Rhododendrons. One linking synapomorphy is the possession of perulae (scales) at the bases of the inflorescences (the sticky things that fall off rhodo blossoms). That all these years I had been wading through stunted, pungent Rhododendrons was not a surprise to me. Labrador tea look a lot like garden rhododendrons, just smaller-leafed, leggier, and hairier. (And smellier.) The flowers, though also smaller than in the garden plants, erupt the same way, from multiple warhead flower buds. Compare picture 2 with picture 4.
Labrador Tea, Rhododendron groenlandicum.
And the flowers are similar. Compare picture 3 with picture 5.
Garden variety Rhododendron. Also comes in white, red, yellow, orange, purple -- even blue.
Rhododendrons (the pretty ones) are a favourite in local landscaping. Almost everyone has at least one. We have four. To thrive, they need an acidic, airy, organic soil that drains quickly. Adding acidic mulch helps, something such as peat moss. Where does peat moss come from?
Irony: we have removed the habitat that contained native Rhododendrons, replaced it with a habitat that cannot, unaided, support Rhododendrons (i.e., a suburb), then planted non-native Rhododendrons, augmenting the soil with material mined from places where wild Rhododendrons once grew.
At least the pretty ones don't smell like Pine-sol.