Photo: J.F. Gaffard, Autoreille, France, CC BY-SA 3.0 · source
Pruning guide · Water or marginal plant
Sweet flag: when and how to prune
Acorus calamus
Sweet flag is best pruned in March and October.
| Pruning months | March and October |
|---|---|
| Native to Belgium | No, planted |
| Poisonous to people and pets | Yes, take care with children and pets |
Sweet flag: when to prune it?
In October, cut off the dead leaves above the water; in March, the rest of the old foliage, before the new shoots appear.
Sweet flag: how to prune it?
- Cut yellow and brown leaves back to a few centimetres above the water surface.
- In autumn, leave some foliage as shelter for insects and clear it in March.
- Always remove the cut leaves from the pond.
How much to cut, and how often?
- There are 2 pruning periods a year: March and October. You don’t have to prune in every one.
What does it mean for wildlife?
- Don’t cut more than you need to: what stays standing gives insects and birds food and shelter.
Caution: Wear gloves if you handle the rhizome a lot and wash your hands afterwards: it is poisonous.
Nearby: related pruning guides
Plant profile: Sweet flag · Pruning calendar and basic rules
This guide is compiled from the Bladwijzer plant profile and pruning calendar.