The Wild iris
Dietes, often called wild iris, African iris, or fortnight lily, is a dependable plant that has earned a place in many home gardens. Known for its striking iris-like flowers and upright, strap-shaped foliage, it’s a fantastic option for gardeners who want something both attractive and easy to maintain.
Originally from southern Africa and nearby regions, these hardy perennials handle a wide range of conditions. Once established, they cope well with heat, drought, and neglect while continuing to produce delicate flowers for much of the year.
If you’re looking for a resilient landscaping plant that requires very little attention, Dietes is well worth considering.
Gardener’s Plant Guide
Botanical Name: Dietes species
Common Name: Wild Iris, African Iris, Fortnight Lily
Plant Type: Evergreen perennial
Hardiness Zones: Typically 8–11 (varies by species)
Sun Requirements: Full sun to light shade
Soil Requirements: Well-drained, humus-rich soil
Water Needs: Moderate when establishing, low once mature
Mature Size: 60 cm – 1.5 m tall depending on species
Bloom Time: Mainly spring to autumn, with occasional flowers year-round
Native Area: Southern Africa and surrounding regions
Plant Description
Dietes plants form dense clumps of upright, sword-like leaves that resemble traditional iris foliage. The evergreen leaves grow in stiff fans and gradually spread through underground rhizomes.
Over time, the clumps become thick and weed-suppressing, making them a practical choice for busy gardeners. Once established, weeds rarely appear within a mature Dietes clump.
The flowers appear on tall, separate stems that rise above the foliage. Individual blooms last only a short time, but plants produce them repeatedly over long periods.
Depending on the species, flowers may be white or pale yellow with striking markings such as purple, apricot, or brown nectar guides.
Popular Dietes Varieties
Several species are commonly grown in gardens and landscapes:
Dietes bicolor
A clumping evergreen perennial growing about 80 cm to 1 m tall. It produces pale yellow flowers with dark purple eye spots. Often called Peacock Flower or Butterfly Iris.
Dietes butcheriana
Sometimes known as the Forest Iris, this species has broad leaves and grows between 50 cm and 1.2 m tall. It features white flowers with apricot markings.
Dietes flavida
A compact species with fan-shaped foliage reaching about 70 cm tall. The flowers are soft yellow with brown nectar guides.
Dietes grandiflora
One of the most widely planted varieties. It grows up to 1.2 m tall and produces large white flowers marked with yellow and violet.
Dietes iridioides
Often called the Fortnight Lily, Cape Iris, or African Iris. This species forms a compact clump about 60 cm tall with white flowers featuring a yellow center and violet highlights.
Dietes robinsoniana
Known as the Lord Howe Wedding Lily, this taller species can reach 1.5 m. It produces fragrant white flowers and originates from Lord Howe Island.
How To Grow Dietes – Basic Care
Once established, these plants require little care. However after 5 – 6 years, the clumps can become congested and need a tidy up.
Best grown in full sun in a well drained soil.
Water in well when planting and through the first summer. D. grandiflora is reasonably drought tolerant once established.
- Position – Full sun
- Soil – Humus rich well drained
- Flowering period – Summer to autumn however will spot flower through the year.
How to Divide Dietes
Dividing is the easiest way to propagate Dietes and rejuvenate older plants.
Step-by-step method
- Water the plant well the day before digging.
- Lift the entire clump from the ground.
- Trim back most of the old foliage.
- Separate the rhizomes into smaller sections.
- Replant divisions into soil enriched with compost or manure.
- Water well and apply a liquid seaweed solution to reduce transplant shock.
Divisions usually establish quickly and begin growing again within weeks.
Landscaping Uses
Because of their durability and attractive foliage, Dietes are widely used in landscaping.
They work well as:
- Low-maintenance ground covers
- Mass plantings
- Border plants
- Roadside or public landscape plantings
- Accent plants in modern gardens
Dietes grandiflora is particularly popular for large landscape plantings because of its toughness and long flowering period from spring through summer.
Dietes robinsoniana, the Wedding Lily, is ideal for subtropical gardens or sheltered locations in cooler climates.
Dietes are available from the following Wholesale Nurseries
55 McDougal Rd Neerim South Victoria 3831 PH: (03) 56281507
Advanced ornamental trees and garden designs and concept plans. Direct to your property combined with specialist knowledge and outstanding service.
www.blericktreefarm.com.au
111 Stanhope Road Theresa Park NSW 2570
Offering a variety of sun hardy Australian natives and exotic trees, shrubs, groundcover's and perennials from semi advanced through to super advanced and semi-mature stock.
www.downesnursery.com.au