Colour-wise, there's often not a lot going on in winter, but the Winter-flowering Iris, or Algerian Iris, is something to lift the spirits in areas of the…
It can tolerate coastal conditions.
Divide plants in spring, never in winter. Or propagate from fresh seed in autumn or refrigerated seed in the spring. If collecting seed for a particular species, be careful to isolate your plant from other species of Agapanthus to avoid natural hybridisation.
Pests, diseases or disorders
Slugs, snails and viruses may be a problem.