Rhododendron (Hybride) 'Helen Martin' Have you spotted any eruptions of colour from rhododendrons yet this year? Rhododendron comes from the Greek, meaning 'tree rose' (although they are not true roses). This ancient genus of plants (older Bonsai Taxus cuspidata Bonsai winkel Rhododendron Trails In the Himalaya, the onset of spring is marked by the blooming of rhododendrons. The flowering trees, found at altitudes ranging from 1500m to over 3600m above sea level, are Rhododendron yakushimanum 'Arabella'