To better view the flowers, remove the past years foliage in late January or early February before the buds emerge to avoid damaging them. Don’t throw the old leaves in the compost heap because it takes more than a year for them to decompose.
Propagation is easy. They will self sow if happy. You may want to discourage this tendency by cutting off the seedpods. This not only keeps the garden tidy but also prevents seeds from sowing into crowns of other plants. Controlled crosses are best to maintain type and color. Although you don’t have to regularly divide them, it’s the best method for creating an exact duplicate of the parent.
I divide in spring or late summer. Late summer is best since flower buds form in early summer. Simply divide the crown and keep it watered until they become established.