How to Fertilize red-leaved rose?
Rose fertilizer every two to four weeks from spring through late summer

red-leaved rose · Rosa glauca
Grow in full sun with fertile, humus-rich, moist but well-drained soil. For best flowering apply a balanced fertiliser and mulch in late winter or early spring - see rose cultivation. Tolerant of poor soil, shade and a north-facing aspect. Suitable for hedging
Rose fertilizer every two to four weeks from spring through late summer