R. 'yakushimanum x May Day'
Rhododendron Hybrid
| Hybridized By | Unknown |
| Seed Parent | ? |
| Pollen Parent | R. 'May Day' |
| 10 Year Height | ? |
| Bloom Time | ? |
| Flower | ? |
| Predominant Colour | ? |
| Leaves | ? |
| Winter Foliage | ? |
| Hardiness | ? |
| Status | Unregistered and unnamed cross. |
| Hybridized By | Unknown |
| Seed Parent | ? |
| Pollen Parent | R. 'May Day' |
| 10 Year Height | ? |
| Bloom Time | ? |
| Flower | ? |
| Predominant Colour | ? |
| Leaves | ? |
| Winter Foliage | ? |
| Hardiness | ? |
| Status | Unregistered and unnamed cross. |