Daylilies (Hemerocallis) and irises are cherished garden additions, celebrated for vibrant blooms and ease of care. Combining different plant types enhances visual appeal, introducing varied textures, forms, and extended color. Understanding how these two popular perennials can successfully coexist creates a harmonious, long-lasting display.
Why Plant Daylilies and Irises Together
Planting daylilies and irises in the same garden bed offers advantages, primarily extending bloom periods and providing contrasting visual interest. Irises typically flower late spring to early summer, with some reblooming into autumn. Daylilies generally begin their display as irises fade, offering continuous summer color. This sequential blooming ensures a dynamic, colorful garden for a longer duration.
Their foliage also complements each other. Irises feature stiff, sword-like leaves; daylilies present graceful, arching, strap-like foliage. This textural difference creates a layered effect, adding depth even when not in bloom. Both perennials are hardy and adaptable, making them suitable companions. Their robust nature makes co-planting a rewarding, low-maintenance endeavor.
Essential Site Preparation
Successful co-planting begins with thoughtful site preparation, focusing on shared environmental needs. Both thrive in full sun, ideally receiving at least six hours daily to promote abundant flowering. While they can tolerate some partial shade, too little sun can reduce bloom production.
Well-draining soil is important for both, especially for irises prone to rot in waterlogged conditions. A rich, loamy soil with a neutral to slightly acidic pH (ideally 6.0-7.0) is suitable for both. Improving heavy clay soils with organic matter (compost or well-rotted manure) enhances drainage and fertility. Conversely, sandy soils benefit from organic amendments to improve water retention, ensuring consistent moisture.
Planting Techniques for Success
Proper planting techniques ensure success when establishing a mixed bed of daylilies and irises. For irises, position the rhizome at or just below the soil surface, ensuring sun exposure. Spread roots in the planting hole, firming soil around them. Daylilies, conversely, should be planted with their crown (where leaves meet roots) about one inch below the surface.
Adequate spacing is necessary for mature growth, air circulation, and preventing overcrowding. Daylily spacing ranges from 16 to 30 inches, depending on cultivar size. Iris rhizomes are planted 8 to 12 inches apart, with clumps 18 to 24 inches apart. After planting, thoroughly water both to settle soil and encourage root establishment.
Ongoing Care for Mixed Beds
Consistent, moderate moisture benefits both daylilies and irises, especially during active growth and bloom. Established daylilies are drought-tolerant but perform best with regular watering. Irises also require water to establish, but once mature, rainfall often suffices, except during very dry spells. Watering deeply and less frequently encourages robust root development.
Fertilization requirements are modest for both; a balanced, low-nitrogen fertilizer is suitable. Over-fertilizing, particularly with high nitrogen, promotes foliage growth at the expense of blooms and can increase soft rot risk in irises. Deadheading spent daylily blooms encourages more flowering. Removing spent iris flower stalks at the base prevents seed formation and maintains tidiness. Division every three to five years is beneficial for both to maintain vigor and bloom production, preventing overcrowding.
Addressing Potential Challenges
Even with careful planning, mixed beds can encounter challenges. Competition for resources occurs if plants are spaced too closely, leading to reduced vigor or flowering. Ensuring adequate initial spacing mitigates this, allowing each plant sufficient room to thrive.
Both plants have distinct susceptibilities to pests and diseases, which can spread in a mixed environment. Irises can be affected by bacterial soft rot in poorly drained soil, and leaf spot. Daylilies can experience issues like leaf streak or spider mites. Regular inspection and prompt removal of affected foliage manages these issues. Maintaining good air circulation and avoiding overhead watering also reduces fungal disease risk.