Yup, momma gives up stalking and blooming in most cases, but she can still throw off some offspring increase. Leave her in the ground and see if more show up coming off the rhizome. If nothing comes maybe you can get an increase from your mother to start with a fresher rhizome. Iris are very interesting and very forgiving of much we do to them, except overwatering or allowing to sit in a depression which collects rain water.
Others will for sure jump in.
And welcome.
