Panicle hydrangea (Hydrangea paniculata 'Kolmakilima' MOONROCK)
Durable Panicle hydrangea, Hydrangea paniculata 'Kolmakilima' MOONROCK, offers lime to white blooms July-Sep and thrives in zones 3-8.
Scroll down to discover growing tips, care requirements, companion plants, and more
Complete Plant Information
Overview
Hydrangea paniculata ‘Kolmakilima’ MOONROCK is a valuable addition to the landscape, celebrated for its vigorous, upright habit and season-long floral display. As a selection of Panicle hydrangea, it brings exceptional cold hardiness, thriving even in the challenging conditions of USDA Zone 3. Gardeners appreciate its reliability, minimal fuss, and the beautiful transformation of its blooms from chartreuse to creamy white.
This cultivar offers dense, cone-shaped inflorescences that can reach impressive lengths up to 14 inches, held stiffly on sturdy stems. The Hydrangea paniculata ‘Kolmakilima’ MOONROCK maintains a manageable stature, typically reaching 4 to 6 feet tall and wide, making it much more compact than older Peegee hydrangea varieties. Its ability to thrive in varying light conditions, from full sun to partial shade, adds flexibility to planting locations.
A key benefit of Hydrangea paniculata ‘Kolmakilima’ MOONROCK is its bloom time, extending color into the landscape from mid-summer well into early fall when many other shrubs begin to fade. Furthermore, its flowers are excellent for floral work, whether fresh-cut or dried, ensuring beauty indoors as well as out.
Fast Facts
- Plant Family: Hydrangeaceae
- Plant Type: Deciduous shrub
- Hardiness Zones: USDA Zones 3-8
- Size at Maturity:
- Height: 4-6 ft
- Spread: 4-6 ft
- Bloom Time: July to September
- Bloom Description: Lime green to white
- Sun Exposure: Full sun to part shade
- Water Needs: Medium
- Maintenance Level: Medium
How to Grow
For optimal results, plant Hydrangea paniculata ‘Kolmakilima’ MOONROCK in an area with organically rich, medium-moisture, and well-drained soil. This cultivar performs well in full sun, which encourages the stoutest stems, but it will tolerate part shade, especially in hotter climates. Proper preparation of the planting hole, ensuring good drainage, is crucial for establishment.
Watering should be consistent, providing medium moisture, especially during the first year and through dry spells; avoid letting the soil become waterlogged. Pruning this Panicle hydrangea is straightforward because it blooms on new wood (current season’s growth). Prune as needed in late winter or early spring before new growth begins.
To encourage fewer, larger flower panicles, thin the plant back to 5 to 10 primary shoots during the late winter pruning period. Although Hydrangea paniculata ‘Kolmakilima’ MOONROCK is naturally compact, you can maintain its best shrub form by pruning it lightly to a height of 6 to 10 feet if a grander presence is desired. Note that in full bloom, the weight of the flowers may cause the branches to arch gracefully outward or downward.
Landscape Uses
The reliable structure and dependable late-season blooms of Hydrangea paniculata ‘Kolmakilima’ MOONROCK make it highly versatile in garden design. Use this shrub for mass plantings within a mixed border to provide continuous texture against evergreens or flowering perennials. It functions effectively as an accent plant or a short, informal hedge where its prominent flower heads can draw the eye.
Because this Panicle hydrangea is notably robust and handles urban stresses well, it is an excellent choice for foundation plantings or as a specimen on a lawn where its multi-stemmed structure can be appreciated throughout the year. Consider pairing it with early-season bloomers like peonies or late-blooming ornamental grasses to ensure visual interest across the entire growing season.
Standout Features
Flower Qualities
- Showy
- Good Cut
- Good Dried
Noteworthy Characteristics
Hydrangea paniculata, commonly called panicle hydrangea, is a vigorous, upright, rapid-growing, somewhat coarsely textured, deciduous shrub that is native to China and Japan. The specific epithet paniculata refers to the arrangement of the flowers in panicles. ‘Kolmakilima’ is an upright selection of panicle hydrangea that features dense, cone-shaped inflorescences made up of sterile flowers that emerge bright lime green and mature to white, with terminal panicles often reaching up to 14” long.
Tolerances
- Air Pollution
Potential Problems
This reliable shrub does face susceptibility to a few common issues, including bacterial wilt, leaf spot, rust, and powdery mildew. Keeping the foliage dry and ensuring excellent air circulation through proper pruning techniques can minimize fungal and bacterial infections. Occasionally, pests such as aphids or mites may appear, particularly if the plant is stressed. A horticultural oil treatment applied early in the season usually manages minor mite or aphid infestations effectively.
Frequently Asked Questions
What hardiness zones is Panicle hydrangea suitable for?
Hydrangea paniculata ‘Kolmakilima’ MOONROCK is incredibly resilient, thriving across USDA Hardiness Zones 3 through 8.
How large does Hydrangea paniculata ‘Kolmakilima’ MOONROCK grow?
Mature plants typically reach a height between 4 and 6 feet, with a comparable spread between 4 and 6 feet.
When does Panicle hydrangea bloom?
This shrub produces its prominent flowers from July through September, starting lime green and aging to white.
What sun exposure does Hydrangea paniculata ‘Kolmakilima’ MOONROCK need?
For the best performance and strongest stems, site this variety where it receives full sun to light part shade.
Conclusion
The Hydrangea paniculata ‘Kolmakilima’ MOONROCK stands out as a modern, highly adaptable landscape shrub, valued for its consistent bloom time and exceptional winter hardiness. Its stately white and lime cones provide significant late-season interest, confirming the Panicle hydrangea as a garden staple. Before planting, confirm that your local growing conditions fall within USDA Zones 3-8 and take advantage of early spring for optimal establishment.
Companion Planting
Selecting companions that share similar cultural needs—medium water and well-drained soil—will ensure the longevity of your planting scheme. Hydrangea paniculata ‘Kolmakilima’ MOONROCK pairs beautifully with broadleaf evergreens like Japanese Holly (Ilex crenata) which provide winter structure when the hydrangea is dormant. Consider planting shorter, contrasting textures nearby, such as ornamental grasses like Switchgrass (Panicum virgatum) or native Coneflowers (Echinacea), whose drier requirements align well once the hydrangea is established.
Design Ideas for Modern Landscapes
The upright, somewhat formal habit of Hydrangea paniculata ‘Kolmakilima’ MOONROCK lends itself well to contemporary and semi-formal designs that rely on structure. Plant them in evenly spaced groups along a walkway for a defined, rhythmic effect, contrasting their stout stems with lower-growing groundcovers. In modern settings, allow the heavy blooms to slightly arch over hardscaping elements like stone patios or gravel beds to soften the lines of hard materials. This specific cultivar’s controlled size makes it an excellent choice for defining the edges of an outdoor living space without overwhelming it.
