Iris ‘Mogul’ is a striking perennial, favored by garden enthusiasts for its elegant blooms and robust nature. Its deep, rich coloration and graceful form add a sophisticated touch to garden landscapes, offering a dependable display of color.
Understanding Iris Mogul
Iris ‘Mogul’ is a Siberian Iris (Iris sibirica) cultivar, known for its tall, upright growth. This plant typically reaches 2 to 4 feet, with slender, grass-like foliage that provides architectural interest even when not in bloom. The flowers feature a deep purple-blue hue, often accented with subtle gold signals at the base of the falls, creating a visually captivating contrast. Blooming occurs in late spring to early summer, providing a vibrant display. It is a hardy perennial, thriving in USDA Zones 3 to 8.
Planting and Establishing Your Iris Mogul
The ideal time for planting Iris ‘Mogul’ is in the fall, a few weeks before the ground freezes, or in early spring after the last threat of frost. These plants perform best in full sun, receiving at least six hours of direct sunlight daily, though they can tolerate partial shade, especially in warmer climates where some afternoon shade can be beneficial. Well-draining soil is important, with a preference for slightly acidic to neutral pH levels. Amending the soil with compost can improve its structure and fertility.
When planting, dig holes approximately 3 to 5 inches deep, ensuring plants are spaced 18 to 24 inches apart for mature growth and good air circulation. Place the rhizome with roots fanned slightly downwards, making sure the crown—the point where the fan of leaves meets the roots—is 1 to 2 inches below the soil surface. After positioning, backfill the hole with soil and gently pat it down firmly to remove air pockets. Thoroughly water newly planted Iris ‘Mogul’ to help settle the soil around the roots and encourage initial establishment.
Ongoing Care for Iris Mogul
Once established, Iris ‘Mogul’ requires consistent care for vigor and abundant flowering. These plants benefit from regular watering, especially during dry spells, with an approximate need of 1 to 1.5 inches of water per week to keep the soil consistently moist but not waterlogged. While relatively self-sufficient, a light application of a balanced, slow-release fertilizer in early spring can support healthy growth and bloom production. Over-fertilization should be avoided, as it can lead to excessive foliage at the expense of flowers.
Deadheading spent blooms improves the plant’s appearance and prevents seed pod formation, which can divert energy from future flower development. Leaving the foliage intact after blooming allows the plant to photosynthesize and store energy in its rhizomes for the following season. Over time, as clumps expand and become overcrowded, the plant’s flowering may diminish. Dividing the clumps every three to five years helps to rejuvenate the plants, maintain their vigor, and ensure continued prolific blooming.
The division process is best done in early spring or late summer to early fall. Carefully dig up the entire clump, gently separate the rhizomes, ensuring each division has healthy roots and a fan of leaves. Replant these divisions at the appropriate depth and spacing, providing generous watering to aid in their re-establishment.
Troubleshooting and Winter Preparation
Iris ‘Mogul’ is generally robust, but issues like sparse blooms or fungal problems can occur. A common reason for sparse flowering is insufficient sunlight; ensuring the plant receives full sun can often resolve this. Overcrowding can also reduce bloom production, highlighting the importance of periodic division to maintain plant health and vitality. Fungal issues, such as leaf spot, can occur, particularly in conditions of poor air circulation or excessive moisture. Addressing these problems involves improving air circulation around the plants and avoiding overhead watering.
Preparing Iris ‘Mogul’ for winter ensures its survival and robust return in spring. In late fall, once foliage yellows and dies back, cut leaves to 4 to 6 inches from the ground. This practice helps remove any potential overwintering sites for pests or fungal spores, contributing to the overall health of the plant. Remove all plant debris from around the base for sanitation. In colder climates, applying a light layer of mulch, such as straw or evergreen boughs, around the plant can provide additional insulation and protect the rhizomes from freeze-thaw cycles that can cause heaving.