Carmen Rhododendron
Rhododendron 'Carmen'
Ericaceae · broadleaf evergreen shrub · introduced
Last updated
A prostrate, mat-forming evergreen shrub barely reaching 1 foot tall in 10 years, spreading to 2 to 3 feet. Openly funnel-shaped, waxy dark red flowers with fine deeper-colored veins, 1⅓ inches wide, in small clusters of 2 to 3 blooms. Early-midseason flowering. A hybrid of R. sanguineum subsp. didymum crossed with R. forrestii subsp. forrestii 'Repens', bred by Lionel de Rothschild at Exbury Gardens (RHS 58).
The waxy dark red flowers are exceptionally substantial for a plant this small, creating a jewel-like effect at ground level. Hardy to -5°F (Zone 7a-9a). Full sun to part shade on acidic, sharply drained soil (pH 4.5-6.0); waterlogged roots are fatal. Extremely slow growth requires patience. Useful for rock gardens, trough plantings, and the front edge of beds where larger rhododendrons would overwhelm. Twenty-one diseases and 15 pests documented at the genus level. All parts contain grayanotoxins and are toxic if ingested.
Quick Facts
Root Colonization (Spring–Fall)
Infection at Bud Break
Apothecia Formation & Spore Release
Aecial Stage (Alternate Host)
+ 13 more — see full disease and pest lists below
Phenological Calendar
| Stage | Typical Window |
|---|---|
| Bud swell BBCH 01-03 | Mar 15-Apr 15 |
| Bloom start BBCH 61 | Apr 1-Apr 20 |
| Full bloom BBCH 65 | Apr 10-Apr 28 |
| Bloom end BBCH 69 | Apr 20-May 8 |
| Bud set BBCH 55-59 | Jul 15-Sep 15 |