Their foliage disappears soon after bloom so it is essential not to dig them up by mistake.
But flowers form mostly on the branch ends, so be sure to prune right after bloom and leave some older growth for insurance.
Bulb foliage must remain after bloom to renew the bulbs for the following year.
Roots and leaves begin growth after bloom and are almost done by spring.
The proper time to prune them back is immediately after bloom.
Iris should be divided about every three to four years, immediately after bloom.
About one-third of the oldest canes can be cut to near ground level now, right after bloom fades.
Be sure to remove faded flowers after bloom so seed heads do not form.
If these shrubs have grown too large for their place in the garden, they can be pruned immediately after bloom.
After bloom, it usually carries two crops on the tree, the old and the new.