How to Fertilize hydrangea 'Mousseline'?
Acidic hydrangea feed monthly spring through summer growth

hydrangea 'Mousseline' · Hydrangea macrophylla 'Mousseline'
Grow in moist but well-drained, humus rich soil, in a lightly shaded spot with shelter from cold, drying winds. Mulch annually in spring. Soil additives may be required to maintain specific flower colours; blue colours are best maintained by growing in acidic soil or ericaceous compost. See shrubby hydrangea cultivation for more detailed advice
Acidic hydrangea feed monthly spring through summer growth