Removing faded flowers
Follow the faded flower's stalk and keep unopened buds in place.

Before you start
Check whether just one flower has faded or the entire flower stalk has finished. On a shared stalk or spike, look for unopened buds farther along.
How to do it
If one flower is finished, trim just its short stalk where you can see the join. If the whole stalk has finished, follow the method for your plant and cut back to a healthy leaf or the base as appropriate.
When to stop and recheck
Leave a flower if you want it to set seed or keep its seed head. If you cannot separate a fading flower from unopened buds, wait for the others to finish.