When to plant and prune Dwarf bulbous iris
Dwarf bulbous iris flowers from early February to late March and the dates below cover planting and flowering.
Planting, flowering and pruning by region
Dwarf bulbous iris is timed from the average frost dates, so its timings shift across the UK. Plot works them out from the Midlands and Lowland Wales baseline using Met Office average frost dates.
| Where you are | Plant | In flower |
|---|---|---|
| South West Coast and Cornwall | early October to late November | early February to late March |
| South Coast and Channel | late September to mid November | early February to late March |
| Greater London (Urban Heat Island) | early October to late November | early February to late March |
| South East and Home Counties | mid September to late October | early February to late March |
| East Anglia | early September to late October | early February to late March |
| Midlands and Lowland Wales | early September to late October | early February to late March |
| Wales and West Coast | mid September to early November | early February to late March |
| Northern England | late August to mid October | early February to late March |
| Scotland Lowlands and Central Belt | late August to early October | early February to late March |
| Scotland Highlands and Islands | early August to mid September | early February to late March |
| Northern Ireland | mid September to late October | early February to late March |
| Channel Islands and Isle of Man | early October to late November | early February to late March |
Growing notes
Depth: plant in autumn up to 15cm deep - deeper planting than usual noticeably improves the chance of reflowering in following years - spacing bulbs 5-7.5cm apart. Often treated as a one- or two-season plant in containers because it rarely persists on heavy or damp soil.
At a glance
- Spacing
- 7 cm between plants
- Eventual height
- 15 cm
- Eventual spread
- 8 cm
- Hardiness
- H5
- Sun
- Full
- Frost tender
- No
- Grows in a container
- Yes, 5 litres or more
- Balcony rating
- 5 out of 5
Feeding
High-potassium liquid feed while in leaf after flowering helps bulbs in containers build up for another year.
Pruning group
No pruning needed; let the grassy foliage die away naturally after flowering
What usually goes wrong
- slugs and snails
- short-lived on poorly drained soil
- bulbs splitting into non-flowering offsets
- iris ink spot disease
Related guides
Timings cross-checked against RHS guidance for dwarf bulbous iris.