Depending on the location of planting in the UK, these agapanthus can be semi-evergreen and hold onto their leaves in milder winters, though will typically lose them in colder regions or spells of weather. However, wrapping in a double layer of horticultural fleece and mulching around the base can safeguard the roots.
Keep well-watered during the growing season, applying a balanced liquid fertiliser each month from spring until the plant flowers. Towards the end of September ease back on the watering and feeding of plants in containers to allow the foliage to toughen up.
Grow Agapanthus plants in rich fertile, well drained soil, in a sunny position. When growing in patio containers, use a soil based compost such as John Innes No.3.