Best of the bunch
Dwarf iris The miniature rockery iris, I. reticulata, grows to just 10cm and brightens up scree beds and containers, its flowers in shades of blue with yellow inner markings or orange splashes, emerging before the grassy tufts of leaves around 30cm high.
Plant the bulbs at twice their own depth in late autumn in a well-drained, sunny spot, adding grit to the soil to help drainage. Good varieties include I. ‘Harmony’, which bears deep velvety blue flowers with yellow lines, and ‘Blue Note’, which is violet blue with feather white markings. I.
‘Katharine Hodgkin’ is another to look out for, with its light blue flowers with rich yellow tongues and a maroon fleck.