Iris foetidissima

As the genus is complex, the flowering characteristics vary greatly however, as a generalisation, Iris blooms start to appear during spring and depending on variety, may be evident throughout the summer and into autumn.

Ideally the Iris plant would need to be planted in a sunny spot so that it can receive at least six hours of sun a day as well as being planted in well drained but moist soil. They do well near water but should be at least 6 inches above water level. Avoid hoeing around the base of the plants as the roots are near the surface and easily damaged. Plenty of mulch can help avoid weed growth around them, although rhizomatous varieties should not be mulched, as this could rot the rhizomes.

Split the irises every year, immediately after flowering has ended. At this point the early summer leaves and flower stems have started to die back, and the late summer leaves have started to grow. Split individual plants with a light spade, leaving the part to be retained undisturbed in the soil. Remove about 30-50% of the total plant mass. The aim is to leave plants about the size that would fit under an A5 sheet of paper. After splitting, cut back the early-summer leaves on the remaining plants, and cut or break off the flower stems. Finally, top-dress the plants.