Ex situ collections:
| Botanical name | Common name | Variety name / Accession name | Accession number | Part of the MLS |
|---|---|---|---|---|
| Rhododendron makinoi TAGG | Rhododendron | - | 100621 | - |
| Rhododendron pleistanthum BALF.F. EX WILDING | Rhododendron | - | 100471 | - |
| Rhododendron scopulorum HUTCH. | Rhododendron | - | 100472 | - |
| Rhododendron elliottii WATT EX BRANDIS | Rhododendron | - | 100496 | - |
| Rhododendron siderophyllum FRANCH. | Rhododendron | - | 100497 | - |
| Rhododendron rigidum FRANCH. | Rhododendron | - | 100498 | - |
| Rhododendron degronianum ssp. degronianum | Rhododendron | - | 100501 | - |
| Rhododendron degronianum ssp. degronianum | Rhododendron | - | 100502 | - |
| Rhododendron oreodoxa var. fargesii (FRANCH.) D.F. CHAMB. | Rhododendron | - | 100541 | - |
| Rhododendron insigne HEMSL. & E.H. WILSON | Rhododendron | - | 100543 | - |