Iris reticulata are superb early flowering bulbs for spring colour. They are compact, so ideal for containers, usually about 10-15cm tall with large, long flowers. You can also plant them direct into the ground to give splashes of brightness and colour. Plant them deep to get the best results and ensure a succession of flower for subsequent years. This particular iris is dark purple to violet making it very striking when it bursts into flower. We planted many bulbs last autumn and this was one of many kicking off the start of the spring show!
- Common name
- Height & spread
- Up to 15cm (6in)
- Bulbous perennial
- Moist, neutral to alkaline
- Partial shade
- Fully hardy
This is a genus of about 300 species of upright, rhizomatous or bulbous, sometimes fleshy-rooted perennials.
The leaves are arranged in fans, sometimes variegated, and the flowers have six tepals (a word used for sepals or petals when they are not easily distinguished). They are grown mainly for their distinctive flowers produced in a range of colours, which are produced in spring and summer. Taller cultivars are suitable for mixed or herbaceous borders, the smaller cultivars for rock gardens, raised beds and troughs, and water irises for the margins of pools and streams. A few that are not frost hardy need protection under glass.
Irises are divided into rhizomatous and bulbous groups and the former group is subdivided into Bearded, Beardless and Crested irises.
These bulbous reticulata irises bear solitary, fragrant flowers in late winter and early spring, that may be pale to deep violet-blue or reddish purple, with a yellow central ridge on each fall (the outer, downturned petals).
Such pretty, delicate flowers are perfect for filling spring containers, as well as rock gardens or en masse under trees. You can also plant them direct into the ground to give little pockets of brightness and colour.
After flowering the bulbs often split and may take several years to reach flowering size again. Plant them deep to get the best results and ensure a succession of flower for subsequent years.
- Grow in well-drained, neutral or slightly alkaline soil in full sun.
- Keep just moist during dormant period.
- After flowering, feed with a high potash fertilizer to encourage large bulbs to form.
- Slugs and snails may be a problem, as may grey mould (Botryris) and thrips.
- Plant Reticulata bulbs 5-10cm apart at a depth twice the height of the bulb, or deeper.
- Lift and separate bulbs in mid-summer to early autumn.
- Sow seed in containers in a cold frame in autumn or spring.
The RHS Joint Iris Committee awarded Iris reticulata an Award of Garden Merit and described it as:
'Dwarf, bulbous perennial to 15cm tall, with narrow, stiffly erect leaves and fragrant, deep violet-purple flowers 8cm wide, each fall marked with a central yellow ridge.'