How to Fertilize Rhododendron 'Leni'?
Ericaceous fertilizer monthly from spring through late summer

Rhododendron 'Leni' · Rhododendron 'Leni'
Grow in moist but well-drained, humus rich, acidic soil. Position in partial or dappled shade, or in full sun in cooler spots where the soil does not dry out. Choose a site away from frost pockets and sheltered from strong winds, and mulch annually, ideally with leaf mould. See rhododendron cultivation for more detailed advice
Ericaceous fertilizer monthly from spring through late summer