Iris 'Colonel Mustard' (Sib)

RHS Plant Profile
Siberian iris 'Colonel Mustard'
Siberian iris 'Colonel Mustard' SIMONA
Herbaceous Perennial

A clump-forming, upright perennial, to around 50cm high, with narrowly sword-shaped, slightly grey-green leaves. Flowers have light yellow standards, with a violet-blue wash on the styles, and rich mustard-coloured falls. Lightly scented. Midseason

Position

Full sun

Soil Types

Loam, Sand

Max Height

0.1-0.5 metres

Max Spread

0.1-0.5 metres

Size

Time to Maturity
2–5 years
Max Spread
0.1-0.5 metres
Max Height
0.1-0.5 metres

Growing Conditions

Loam Sand
Moisture
Moist but well–drained
pH
Neutral or Acid

Position

Full sun
Aspect
South–facing or West–facing
Exposure
Sheltered
Hardiness
H7

Colour & Scent

Fragrance Flower
Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Iridaceae
Native to GB/Ireland
No
Foliage
Deciduous
Habit
Clump forming
Potentially harmful
Harmful 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
Genus
Iris may be rhizomatous or bulbous perennials, with narrow leaves and erect stems bearing flowers with 3 large spreading or pendent fall petals, alternating with 3 erect, often smaller, standard petals, in late winter, spring or early summer
Name Status
Accepted
Horticultural Group
Sibirica irises are rhizomatous perennials, to 1.2m tall, with narrow leaves and erect stems bearing up to 5 beardless flowers 6-7cm wide in early summer. Form and colour vary considerably among cultivars

How to Grow

Cultivation

Thrives in a sunny position, in moist but well-drained, ideally neutral to slightly acid soil. Will tolerate some dappled shade, though they flower best in full sun. Divide every three to five years to maintain vigour. See bearded iris cultivation for more detailed advice

Propagation

Propagate by division, see dividing irises for more detailed advice

Suggested planting locations and garden types

  • City and courtyard gardens
  • Cottage and informal garden
  • Patio and container plants
  • Flower borders and beds
  • Wall side borders

Pruning

Remove spent flower stems after flowering, and any dying foliage in autumn

Pests

May be susceptible to aphids, slugs, snails and thrips

Diseases

May be susceptible to aphid-borne viruses, bacterial soft rot and grey moulds; see Iris diseases