Rhododendron 'Cunningham's White'
Description: A large, very hardy evergreen shrub with dark-green ovate leaves. In late spring (May), many trusses of white funnel-shaped flowers with yellow centres open from mauve - pink flushed buds.
Uses: Suitable for use as a hedge or screen.
Climate/Position: Semi shaded position.
Height/Spread: 1.8 x 1.8 metres.
Soil Requirements: Rhododendrons prefer soils with a low pH or ericaceous soil to avoid chlorosis or yellowing of the leaves. However, R. 'Cunningham White' is more tolerant of lime than many other Rhododendrons and so is invaluable for displays in more alkaline soils.
Pruning: Generally avoid pruning. Flower stalks can be pinched out (by finger and thumb rather than secateurs) when flowering is complete. Well established plants will respond well to regenerative pruning if required.
Special Requirements: Applying a mulch regularly around the plant will help moisture retention in the soil. Where plants struggle a little if not grown in soil with low pH, then Rhododendrons will always benefit from an annual feed of sequestered iron to ensure the plants do not suffer from iron deficiency which is indicated by interveinal chlorosis or yellowing of leaves between the veins.
Additional Interest: Raised by James Cunningham in Edinburgh in about 1830, a hybrid between R. caucasicum (f) × ponticum var. album
Noted as very hardy and more lime tolerant than many other Rhodos and has commonly been used in commercial production on nurseries as a rootstock for grafting other cultivars onto, making them slightly more lime tolerant.