Bicolor Iris

If you’re looking for a flower that truly stands out, consider the bicolor iris. This two-toned floral beauty brings a striking contrast to any garden bed or border.

Their unique petals display two distinct colors, creating a dramatic effect that’s hard to miss. They are surprisingly easy to grow, too, offering a big visual payoff for a modest amount of effort. Let’s look at how you can add these captivating plants to your own space.

This term refers to any iris variety where the falls (the downward-curving petals) and the standards (the upright petals) are different colors. Sometimes, the contrast is within a single petal. This natural artistry is the result of careful breeding and selection over many years.

The effect can range from subtle to bold. A soft yellow standard against a white fall is elegant. A deep purple standard over a bright white fall is jaw-dropping. This variety means there’s a bicolor iris for almost every garden color scheme.

Popular Bicolor Iris Varieties to Try

With so many choices, it can be hard to pick. Here are a few reliable and stunning varieties that perform well in many gardens:

‘Immortality’ Reblooming Bearded Iris: Pure white standards with just a hint of lemon-yellow on the falls. It’s fragrant and often blooms twice in a season.
‘Dutch Chocolate’ Bearded Iris: Rich, coffee-brown standards with velvety deep purple falls. It’s a unique and sophisticated color combination.
‘Queen’s Circle’ Siberian Iris: Delicate white standards centered with a ring of violet-blue on the falls. It’s a graceful, clump-forming variety.
‘Variegata’ Sweet Iris (Iris pallida): Known for its foliage as much as its flowers. Its leaves are striped with cream and green, and it produces lovely lavender and yellow blooms.

How to Plant Bicolor Irises Correctly

Getting the planting right is the first step to success. Most irises, especially bearded types, demand one key thing: good drainage. They will rot in soggy soil.

Choosing the Right Spot

Irises need at least 6 to 8 hours of direct sunlight daily to bloom their best. Less sun means fewer flowers. Ensure the area doesn’t collect standing water after rain.

Preparing the Soil

They prefer a neutral to slightly acidic soil. If you have heavy clay, amend it with coarse sand or compost to improve drainage. Raised beds are an excellent option for wetter climates.

The Planting Process (For Rhizomes)

Dig a shallow hole about 4 inches deep and form a small mound of soil in the center.
Place the rhizome (the thick, horizontal root) on the mound, spreading the roots down the sides.
Backfill the hole so the top of the rhizome is just barely exposed to the sunlight. It should not be buried deeply.
Space rhizomes about 12 to 24 inches apart, as they need room to multiply.
Water them in well to settle the soil around the roots.

Caring for Your Two-Toned Blooms

Once established, irises are quite low-maintenance. A little attention at key times makes a huge difference.

Watering and Feeding

Water newly planted irises regularly to help them develop roots. Established plants are drought-tolerant. They only need supplemental water during very dry spells. Overwatering is a common mistake.

Feed them in early spring with a low-nitrogen fertilizer or a balanced one. Avoid high-nitrogen formulas, which promote soft rot and leafy growth at the expense of flowers. A second light feeding after blooming can help recharge the rhizome.

Deadheading and Pruning

After each flower fades, snap off the spent bloom stalk. This keeps the plant looking tidy and prevents it from wasting energy on seed production. Once all blooms on a stalk are gone, cut the entire stalk down to the base.

In late fall, trim the leaf fans back to about 6 inches. This removes old, potentially diseased foliage and reduces wind damage over winter.

Dividing and Propagating

Every 3 to 5 years, your irises will become overcrowded. The center of the clump will stop blooming. This means it’s time to divide them. The best time to do this is about 6 to 8 weeks after blooming finishes, usually in late summer.

Use a garden fork to gently lift the entire clump from the ground.
Shake or wash off the soil so you can see the rhizomes clearly.
Break or cut apart the healthy, firm rhizomes from the old, woody center. Discard any soft or rotten pieces.
Trim the leaves to about one-third of their height to reduce stress on the plant.
Replant the fresh divisions as described above, giving them plenty of space.

Common Problems and Simple Solutions

Even tough plants have a few issues. Here’s what to watch for:

Lack of Blooms: Usually caused by too much shade, overcrowding, planting too deep, or too much nitrogen fertilizer. Check these factors first.
Iris Borer: This is the most serious pest. Look for notched leaves in spring and watery, rotten rhizomes later. Destroy infected leaves and rhizomes. Good sanitation in fall is the best prevention.
Soft Rot: A smelly, mushy rot often following borer damage. Dig up the plant, cut away all soft tissue, soak the rhizome in a bleach solution (10%), let it dry in the sun for a day, and replant in fresh soil.
Leaf Spot: Fungal disease causing brown spots. It’s rarely fatal. Remove affected leaves and avoid overhead watering to improve air circulation.

Design Ideas for Your Garden

Bicolor irises are versatile design elements. Their vertical structure and vivid colors make them perfect for certain roles.

Plant them in groups of three or five of the same variety for a strong visual impact. They make excellent mid-border plants, rising above spring bulbs and in front of later-blooming perennials like phlox or coneflowers. The smaller Siberian types work beautifully along the edge of a pond or stream, as they tolerate moister soil.

Consider color echoing. A purple and white iris looks fantastic near a white peony or behind a drift of purple catmint. Their foliage remains attractive all season, providing a stiff, grassy texture that contrasts well with rounded or mounded plants.

FAQ About Bicolor Irises

Q: When do bicolor irises typically bloom?
A: Most bloom in late spring to early summer, though some reblooming varieties will flower again in late summer or fall.

Q: Are these irises deer resistant?
A: Yes, irises are generally considered deer-resistant due to their tough foliage and rhizomes. Deer might sample them but rarely devour them.

Q: Can I grow bicolor iris in a container?
A: Absolutely. Use a wide, shallow pot with excellent drainage. Be prepared to water more frequently and divide the clump sooner than in-ground plants.

Q: What’s the difference between a bicolor and a blend iris?
A: A bicolor has two distinct, separate colors. A blend has two or more colors that softly intermingle or wash into each other on the petal.

Q: How long do the flowers last?
A: Each individual bloom may last a few days, but a well-established clump will produce multiple buds per stalk, providing a show for several weeks.

Adding a bicolor iris to your garden is a sure way to inject a dose of sophisticated drama. Their striking two-toned floral beauty offers a unique visual interest that few other perennials can match. With their simple needs—lots of sun, good drainage, and occasional dividing—they reward you with reliable color and elegant form year after year. Start with one or two varieties that catch your eye, and you may soon find yourself making room for more of these captivating plants.