|'P.J.M.' rhododendrons are the result of crosses between R. carolinianum and R. dauricum var. sempervirens. They were first developed by the Weston Nurseries in Hopkinton, Massachusetts.
'Henry's Red' has a broad, upright habit and bears an abundance of showy, vivid, deep red flowers beginning in mid-April. The 'P.J.M.' group of rhododendrons are smaller, growing to a height of 3 to 6 feet tall. Form is rounded and foliage is leathery and dark green until fall when it turns almost purplish. One of the reasons the 'P.J.M.' group is such a heavy flowerer is that the plant does not set seed. An excellent rhododendron for the New England states.