how to divide Crocosmias

the ones at the top closest to the leaves or soil surface, as they are the new ones. I usually keep a couple of old ones on just coz that was the way my dad used to do it.

All of the string if you want them to flower sooner. Keep the string intact. They do better that way, otherwise you have to wait for the string of bulbs (corms actually) to form for the plant to really flower well.