Dietes

( dy - EE - teez )

At-A-Glance Information

These herbaceous perennials that grow from rhizomes are commonly called Fortnight Lily, Wood Iris, Butterfly Iris, Japanese Iris and African Iris. These plants are native to the African continent and Australia, and need full sun or partial shade (depending on the climate) and moderate to regular water. African Irises produce fans of narrow evergreen leaves and flowers appear on branched stalks in spring summer, falling on two-week intervals. Flowers come in white, cream and yellow with contrasting blotches of orange, yellow, or brown. Each flower lasts only one day. They are fantastic in pebbles and rocks and amongst shrubs and other long-lived perennial plantings in borders. Take care when planting Dietes in your garden, as some species can be poisonous to humans and animals, and can also cause skin irritation in susceptible individuals.

Dietes Species and Varietals

There are six species included in the genus Dietes, which is a member of the plant family Iridaceae. African Iris grows best in zones 8, 9, 12-24, H1 and H2. To find your zone, click here: Zone Map.

Dietes bicolor (African Iris, Fortnight Lily, Yellow Wild Iris)
Native to South Africa, this plant produces 2-3 foot tall stems topped with light yellow flowers that have blotches that range from maroon to dark brown. Flower stems last one year and then die back to the ground. This is a particularly drought-tolerant species for the genus.

Dietes grandiflora (Dietes iridioides 'Johnsonii') (Fortnight Lily, Large Wild Iris, African Iris, Fairy Iris)
Also from South Africa, this plant grows to 3 feet tall and has brown-marked bases of inner flower segments. Blooms are light yellow, and also have tufted darker yellow sections. Flowers last for about three days before expiring. Cultivars include 'Variegata' (with creamy yellow margins on leaves), and 'Sunstripe' (with yellow-striped leaves).
Dietes Hybrid Species
Hybrid species include those outlined below.
'Lemon Drops'
Ivory blooms with yellow blotches. 
'Orange Drops'
Ivory blooms with orange blotches. ​
'Jack Catlin'
1.5 to 2 feet tall and 3-4 feet wide, with dark green foliage. White flowers have yellow markings. 

​Dietes iridioides (Dietes vegeta, Moraea iridioides) (African Iris, Fortnight Lily, Morea Iris)
This species hails from East Africa, and produces 3 foot tall stems topped with white flowers with yellow-orange blotches. Style arms are violet. Deadhead individual flowers, not stems, until after one year. A popular variety is 'John's Runner', which has white flowers marked with yellow and purple and only grows to about 1-2 feet tall and 2-3 feet wide.

Dietes robinsoniana (Lord Howe Wedding Lily)
This species is endemic to Lord Howe Island in Australia, and is the largest species in the genus Dietes. Leaves are long, green, and strappy, and plants can reach up to just under 5 feet tall. Flowers bloom from September to December in the plant's native range. Flowers are white with yellow. 

Caring for Dietes

These can be planted from containers, as their rhizomes are not sold at any time of the year. They need good soil and regular watering when initially planted but after they are established, they will do fine with even poor soil and little water. Clumps can remain for years, but should be divided in fall or winter every few years. 

Propagation

Problems and Pests

Gallery

Camellias are great candidates to be grown as container plants on your patio.
A field of thea sinensis
Camellia hiemalis 'Shishi Gashira'

Videos

A video all about growing camellias successfully
Propagating camellias

Resources

Wikipedia: Dietes
The New Sunset Western Garden Book: The Ultimate Gardening Guide (2012) - Page 289, Dietes
If you have any questions, comments, concerns, or photos you’d like to add to the gallery, please let me know by sending me a message using the button below!
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