About

Iris wilsonii, the Wilson iris, is a rhizomatous perennial producing narrow, greyish foliage and pale-yellow flowers with brownish veins on the falls in early summer. A rewarding and ornamental species iris for a sunny, moist border.

About the genus

Iris are rhizomatous or bulbous perennials with narrow, often sword-shaped leaves and erect stems bearing flowers with three large, spreading or pendent fall petals alternating with three erect, often smaller, standard petals in late winter, spring or early summer. One of the most varied and spectacular of all plant genera, encompassing everything from tiny bulbous species to tall bearded border irises.

Growing conditions

SunlightFull sun, Partial shade
Soil typeChalk, Clay, Loam, Sand
Soil pHAcid, Alkaline, Neutral
Soil moistureMoist but well-drained, Poorly-drained
AspectWest-facing, South-facing, East-facing
ExposureExposed, Sheltered
UK hardinessH7

Plant details

Plant typeBogs, Herbaceous Perennial
HabitBushy
FoliageDeciduous
Height0.5-1 metres
Spread0.1-0.5 metres
Time to full height2-5 years
Suggested usesCity and courtyard gardens, Coastal, Cottage and informal garden
Native toW China
ToxicityHarmful if eaten. Wear gloves and other protective equipment when handling. Pets: Harmful if eaten. For further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants

Care notes

CultivationGrow in any good garden soil that is preferably moist and humus rich. In drier soils, dig in well-rotted organic matter before planting then apply as a mulch each spring
PruningRemove any dying foliage in autumn, old flower stems can be cut down after flowering
PropagationPropagate by division of rhizomes from midsummer to early autumn
Pest resistanceMay be susceptible to slugs, snails and thrips
Disease resistanceMay be susceptible to aphid-borne viruses, bacterial soft rot and grey moulds; see Iris diseases