Mondo grass (Ophiopogon japonicus) is a popular, grass-like evergreen perennial often used as a groundcover. Yes, it does flower, although many gardeners never notice the blooms. Unlike showy garden plants, Mondo grass flowers are quite small and are often hidden by the plant’s dense, strap-like foliage, making them inconspicuous to the casual observer.
Flowering: The Answer and Appearance
Mondo grass blooms typically appear from mid-to-late summer, adding subtle texture to the evergreen foliage. These flowers are borne on short, stiff racemes, or spikes, which arise from the base of the plant. The flower stalks are often only two to four inches long, keeping the blooms nestled close to or slightly below the leaf blades.
Each individual flower is small, usually less than a quarter of an inch across, and has a delicate, bell-shaped form with six petals. The coloration is muted, ranging from pure white to pale lavender or a light pinkish-white tint, which further contributes to their hidden nature.
Post-Flowering Development
Once the brief flowering period is complete, the plant develops fruit, which is often more noticeable than the flowers themselves. The tiny pollinated flowers transition into small, spherical berries that mature over the late summer and into the fall. These berries are hard, round, glossy, and serve as the mechanism for seed dispersal.
The fruit exhibits a striking, metallic coloration, ranging from a deep, cobalt blue to a near-black hue on standard green varieties. Measuring roughly a quarter of an inch in diameter, these berries persist throughout the late fall and into the winter, offering a unique visual element against the evergreen foliage. While the berries contain seeds for propagation, Mondo grass is more commonly spread through its underground runners, or stolons.
Factors Affecting Bloom Production
Several common reasons explain why a gardener might not observe the flowers or subsequent berries. Plant maturity is a significant factor; very young or recently transplanted clumps focus energy on establishing a root system rather than producing blooms. Plants generally need a season or two to settle in before they reliably flower.
Light conditions also play a large role in reproductive efforts. While Mondo grass tolerates deep shade, overly dense shade can inhibit flower production altogether. A location receiving filtered sunlight or partial shade is often where the most robust flowering occurs. Furthermore, some popular cultivars, such as the dark-leaved ‘Nigrescens,’ tend to have less noticeable blooms, despite their pale pink flowers contrasting sharply with the near-black foliage.