Not much is known about the origins of 'Ponticum Roseum', but it is thought to be a cross between the Pontic Rhododendron (R. ponticum) and Great Laurel (R. maximum). In the USA it was sold in the 1950s – 1960s as ‘Maximum Roseum’. However, it is clearly not a form of R. maximum, but a distinct hybrid. Just to complicate things, there are apparently three different clones on the market under the same name.
'Ponticum Roseum' grows strongly and in favourable conditions can reach 2 metres in ten years, though in Finnish winters frosts and heavy snow may check growth, keeping it much lower.
The flowers resemble those of R. ponticum and are a pinkish lilac. The spotting on the petals is orange-brown.