Iris unguicularis Walter Butt is a lovely lavender winter flowering iris that is sweetly scented. They have erect stems bearing flowers with 3 large spreading petals. Iris unguicularis Walter Butt flowers appear in winter and early spring. They are extremely susceptible to slugs, especially very small ones.
Plant in well drained soil, in a sunny sheltered spot. Sharp drainage is essential as the rhizomes will rot if the soil is too damp. Cultivate the soil to a depth of 15cms before planting and mix in something like bone-meal or well rotted garden compost at this stage.
Flowering height: 18″ (45cms)
Flowering time: January-February
Soil type: Light soil
Aspect: Ideally a south facing aspect.
Using shears cut back leaves in June. This allows the sun to ripen the rhizomes as this is essential for good flowers. Once the clumps become too large and congested, this is when you need to cut them back.
They will need to be split and divided after 3-5 years. This is best done after flowering and before the leaves have died back.
Propagate Iris unguicularis by division in summer/early autumn. Dig-up the clump and prize it into smallish pieces. If the clump is congested use two forks back-to-back. Replant the divisions immediately in their flowering positions.
New season top quality bulbs dispatched from September onwards.