Growing Algerian Iris Plants: How To Care For Iris Unguicularis

Every child has heard about the ugly duckling, a cautionary tale about an orphan chick raised by a mother duck who grew into a beautiful swan.

No more apparent is this story than in the case of the perennial Algerian iris, Iris unguicularis (EYE-ris un-gwee-kew-LAIR-iss).

algerian irisPin

This unusual member of the Iridaceae family (and part of the Limniris subgenus) is a messy, unattractive clump of grasslike leaves during much of the year.

Then, winter comes, and the plant becomes a gorgeous floral display while most other plants are dormant.

Native to the Mediterranian countries of Algeria, Greece, Turkey, and Tunesia, this unusual iris is also known as the winter iris due to its backward flowering habits.

Make no mistake, if you love irises and want flowers all year round, Algerian iris is an absolute must for your garden!

Iris Unguicularis Care

Size & Growth

Best planted in the spring, the Algerian iris can grow to 18″ inches tall in dense clumps that are about as wide. 

They’re initially slow to germinate but will become moderately fast growers. The dark green foliage is long, straplike, and often arching in nature.

Flowering And Fragrance

Blooming from November through March, this iris can be a little hard to see at times due to the shorter flower stalks.

The sweet-smelling beardless flower buds are a bluish tone that opens into a lilac or lavender-colored flower, which bears a yellow center and darker purple veins. Details on bearded iris here.

These blooms have distinct styles (the stem on a female flower which supports the stigma), lending to both the species name unguicularis (meaning “with a claw”) and the alternate scientific name Iris stylosa (having styles).

As the plants age, they’ll produce increasing numbers of flowers which can exceed 100 in a single season.

Some growers have described the flower scent to resemble a mix of vanilla and lemon.

Several cultivars exist with variations of flower color, such as:

  • ‘Alba’ – white
  • ‘Cretensis’ – lilac-pink
  • ‘Dazzling Eyes’ – bluish-purple with purple and white stripes in the eye zone
  • ‘Mary Bernard’ – dark bluish-purple
  • ‘Mia’ – violet-blue
  • ‘Walter Butt’ – pale lavender

Light & Temperature

Algerian Iris is a plant that thrives in full sun all year round.

A little light shade in the summer afternoon is pleasing, but you should avoid shadows beyond this point if you want the best blooms.

It’s also best to keep it in lower humidity than other irises.

Winter iris can be grown outdoors in USDA hardiness zones 7 to 9, although it will tolerate hotter areas.

You may also bring it indoors to overwinter in a sunny window in cooler zones where the winter is harsher.

Watering And Feeding

When to water this plant can be a little confusing. Give it some water during the spring and fall when the soil is dry 2” to 3″ inches down.

While most plants need more water in the summer months, winter iris prefers to have a drier rhizome.

As a result, you should only add a little water as needed to prevent the soil from completely drying out in summer and winter.

Another counter-intuitive aspect of caring for Algerian irises is that they don’t need to be fed.

Some growers do choose to ass a little vermicide or liquid seaweed fertilizer after flowering is over or just before winter.

However, this is a practice best used only on potted plants, which tend to use up the soil’s resources faster.

Soil & Transplanting

Good drainage is essential for this iris, but it needs little beyond this.

Sandy and loose clay soils are ideal for the winter iris aim for a neutral to slightly alkaline soil pH, especially when purchasing a potting soil mix for Iris.

Because the plant prefers nutrient-poor soil, they’re well adapted to many commercial cactus soils.

As with many rhizomatous irises, the Algerian iris doesn’t like to be disturbed.

However, it can quickly become overcrowded, so you should divide the plant every 3 to 5 years, regardless of whether it’s in a pot or the ground.

Grooming And Maintenance

Young plants would need some winter protection if you didn’t plant them in early spring.

It is especially true for iris plants grown from seed or if you’re expecting a winter that’s less than mild.

Due to its unusual blooming period and short stalks, you’ll want to trim back some of the foliage in late autumn.

Focus on dying, diseased, or discolored leaves, but you may also trim off the leaf tips so the blooms will be more visible.

Deadhead any spent blooms throughout the winter and give the plant another trim to tidy it up after the blooming season has ended.

How To Propagate Algerian Iris?

As one of the two subgenera Iris that grow from rhizomes instead of bulbs, the Algerian iris is best propagated through division, although it may also be grown from seed.

Winter Iris Pests Or Diseases

Winter Iris is one challenging iris species with a high tolerance for drought.

It’s also resistant to both deer and rabbits, as well as most pests.

However, be wary of slugs and snails, the two primary enemies of winter irises.

They can easily conceal themselves in the dense clumps and regard your iris blossoms as a tasty snack.

Fungal infections are common because they prefer drier conditions, although they’re also susceptible to the same bacterial and viral diseases as other illnesses.

They also have the same toxicity, which can be dangerous to pets and cause a range of digestive problems in humans.

Iris Unguicularis Uses

The cut flowers of an Algerian iris can last for 4 to 5 days in a vase, making them an excellent table accent for Christmas dinner.

They’re rather messy and grasslike during the summer months, making them a good choice for garden borders and walls.

As with most irises, they’ll do well in containers, as long as the container is wide enough, but their shallow root systems also make them a great choice for window boxes.

Finally, they’re a perfect addition to garden beds alongside plants that bloom in spring and summer, as this will mean flowers all year round.

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