Belle Heller Blooming Pink Rhododendron Flowers in the Parang Mountains. Stock Image Image of flower, clear: 222221659 Olivenbaum Genomic selection in hybrid breeding Zhao 2015 Plant Breeding Wiley Online Library Rhododendron 'Ginny Gee' 5L Ashwood Nurseries During May, our renowned rhododendron collection reaches its peak. Collected from around the world over more than 200 years, these rare and historic plants form one of the garden's defining features.