Hydrangea arborescens (Smooth Hydrangea)
Smooth Hydrangea, Wild Hydrangea
Native to the Eastern United States, Hydrangea arborescens (Smooth Hydrangea) is a widely branched deciduous shrub, acclaimed for its creamy-white flower clusters that brighten shady areas and bring life to the garden.
What is Hydrangea arborescens?
Hydrangea arborescens, also known as Smooth Hydrangea or Wild Hydrangea, is a deciduous shrub native to the United States, specifically in the eastern and southern regions.
Habit and Size: It typically grows in a rounded habit to 3-6 feet (90-180 cm) tall and as wide. The stems of the plant are quite sturdy, allowing it to maintain its shape. The bark is thin and gray-brown, often exfoliating in thin strips on mature stems.
Flowers and Blooming Season: It boasts domed to nearly rounded blossoms, which open lime-green and change to brilliant creamy white before switching to a tan shade in the fall. Unlike many other hydrangeas, the flower color of H. arborescens is not affected by soil pH.
Foliage: The leaves of this hydrangea are broad egg-shaped, sharply toothed, dark green. They turn butter-yellow shades in fall, extending the season of interest of this magnificent flowering shrub.
Blooming Season: Hydrangea arborescens typically flowers from June to September, with the exact timing depending on local conditions and the specific variety.
Hardiness: It’s hardy in USDA zones 3-8, making it adaptable to a wide range of climates. It’s more heat and cold tolerant than other hydrangea species.
Uses: This hydrangea species is used for various landscaping purposes, including border plantings, woodland gardens, or as a specimen or accent plant. Its ability to tolerate heavy pruning makes it versatile in design use.
Pollinators: The flowers attract a variety of pollinators, including bees and butterflies.
Toxicity: Like most hydrangeas, H. arborescens is mildly toxic if ingested. It can cause stomach upset in humans and pets.
Deer and Rabbit: Hydrangea arborescens can be appealing to deer, especially in areas where their natural food sources are scarce. Rabbits may also nibble on the plant.
Why Should I Grow Hydrangea arborescens?
There are many reasons why Hydrangea arborescens, or Smooth Hydrangea, is a worthy addition to your garden. Here are some key reasons to consider:
Versatility: With its compact size and rounded growth habit, Hydrangea arborescens fits well in a variety of garden spaces. It works beautifully in borders, woodland gardens, or as a standalone specimen.
Stunning Blooms: This hydrangea is known for its spectacular clusters of creamy white flowers, which can create a stunning visual impact in your garden from late spring to early fall. The cultivar ‘Annabelle’ is particularly impressive with its large, spherical blooms.
Tolerance and Hardiness: Hydrangea arborescens is more cold and heat tolerant than many other hydrangea species, making it a good choice for gardens in a range of climates.
Native Species: As a native plant to the United States, it can be an excellent choice for a native or wildlife garden. It’s adapted to local growing conditions and provides habitat and food for local wildlife.
Soil pH Adaptability: Unlike some other hydrangeas, the color of Hydrangea arborescens blooms is not affected by soil pH, reducing the need for soil amendments.
Pollinator Attraction: The flowers of Hydrangea arborescens attract bees, butterflies, and other pollinators, promoting biodiversity in your garden.
Ease of Care: This plant is relatively easy to care for, with no significant disease or pest issues. It’s also tolerant of heavy pruning, allowing you to easily control its size and shape.
Guide Information
| Hardiness |
3 - 8 |
|---|---|
| Heat Zones |
1 - 9 |
| Climate Zones | 1, 1A, 1B, 2, 2A, 2B, 3, 3A, 3B, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, A3 |
| Plant Type | Shrubs |
| Genus | Hydrangea |
| Exposure | Full Sun, Partial Sun |
| Season of Interest |
Summer (Early, Mid, Late) Fall |
| Height |
3' - 6' (90cm - 180cm) |
| Spread |
3' - 6' (90cm - 180cm) |
| Maintenance | Low |
| Water Needs | Average |
| Soil Type | Clay, Loam, Sand |
| Soil pH | Acid, Neutral |
| Soil Drainage | Moist but Well-Drained, Well-Drained |
| Characteristics | Dried Arrangements, Cut Flowers, Showy |
| Native Plants | Alabama, Arkansas, Connecticut, Delaware, Florida, Georgia, Illinois, Indiana, Kansas, Kentucky, Louisiana, Maryland, Massachusetts, Midwest, Mississippi, Missouri, New Jersey, New York, North Carolina, Northeast, Ohio, Oklahoma, Pennsylvania, South Carolina, Southeast, Southwest, Tennessee, United States, Virginia, West Virginia |
| Attracts | Bees, Butterflies |
| Landscaping Ideas | Beds And Borders, Hedges And Screens, Patio And Containers |
| Garden Styles | City and Courtyard, Informal and Cottage, Traditional Garden |
Favorite Hydrangea arborescens Cultivars
Garden Design With Hydrangea arborescens
Hydrangea arborescens, or Smooth Hydrangea, can play a versatile role in garden design due to its stunning blooms, rounded form, and compact size. Here are some design ideas incorporating this plant:
Mixed Borders: Incorporate H. arborescens in mixed borders along with other flowering shrubs, perennials, and ornamental grasses. Its mid-sized stature makes it suitable for the middle or back of a border, depending on the size of your border.
Woodland Gardens: Because this plant is native to woodlands, it can be a great addition to a woodland garden design. Pair it with shade-tolerant woodland plants like Hostas, Ferns, and Astilbes.
Accent or Specimen Plant: The impressive flowers of H. arborescens, particularly the ‘Annabelle’ variety, make it an excellent choice for a specimen or accent plant. Use it as a focal point in a garden bed or at a corner of your house.
Hedge or Mass Planting: Plant several H. arborescens together to create a low hedge or a mass planting. This can be particularly effective along a driveway, fence, or property boundary.
Container Plantings: Smaller cultivars of H. arborescens can be grown in large pots or containers, making them suitable for patios or small gardens.
Cut Flower Gardens: The flowers of H. arborescens are excellent for cutting and can be used in fresh or dried arrangements. Consider adding this plant to a cut flower garden.
Wildlife Gardens: As a native plant, H. arborescens can be a great addition to a wildlife-friendly garden. Its flowers attract bees and butterflies, adding dynamism and biodiversity to your garden.
Remember to consider companion plants that complement the hydrangea’s growing conditions and aesthetic. Perennials that bloom at different times can extend the flowering season, while contrasting textures or colors can create visual interest.
Companion Plants
Hydrangea arborescens, or Smooth Hydrangea, pairs well with a variety of companion plants that complement its growing conditions and aesthetic. Some ideal companion plants include:
Hostas (Hosta spp.): These shade-loving perennials offer bold, textural foliage that pairs well with the large flower heads of Hydrangea arborescens. Their wide range of colors and forms also add depth to the garden design.
Ferns: Ferns can provide a delicate texture contrast to the more substantial leaves and blooms of the hydrangea. Choices like the Lady Fern (Athyrium filix-femina) or Japanese Painted Fern (Athyrium niponicum) would be good options.
Astilbes (Astilbe spp.): These perennials thrive in similar conditions as H. arborescens and their feathery, plume-like flowers provide a nice textural contrast to the hydrangea’s large, rounded flower clusters.
Japanese Anemones (Anemone x hybrida): Japanese Anemones bloom in late summer and fall, extending the blooming season in the garden after the hydrangea’s flowers have faded.
Heuchera (Heuchera spp.): Also known as Coral Bells, these perennials are known for their attractive, often colorful foliage. They can add a splash of color to the garden and prefer similar growing conditions.
Lungwort (Pulmonaria spp.): These shade-loving perennials have attractive foliage and early spring blooms, which can add interest to the garden before the hydrangea begins to flower.
Lamium (Lamium maculatum): This ground cover can fill in spaces between larger plants and offers variegated foliage that brightens shady spots.
Bleeding Hearts (Dicentra spectabilis): This spring bloomer can provide early season interest and its delicate, fern-like foliage offers a nice contrast to the hydrangea’s broader leaves.
Ornamental Grasses: Grasses like Japanese Forest Grass (Hakonechloa macra) or Sedge (Carex spp.) provide texture and movement in the garden, complementing the more static form of the hydrangea.
Rhododendrons or Azaleas: These acid-loving shrubs can be a good match in terms of soil pH requirements and offer a different form and flower style.
As always, make sure to consider the specific needs of each plant in terms of light, soil, and water conditions to ensure a successful and beautiful garden design.
Growing Tips
Growing Hydrangea arborescens, or Smooth Hydrangea, is relatively straightforward. Here are some steps to guide you:
Select the Right Location: Hydrangea arborescens prefers partial shade, but it can tolerate full sun if it’s given enough moisture. A spot with morning sun and afternoon shade is often ideal. It can grow in full shade but might produce fewer flowers.
Prepare the Soil: This hydrangea prefers rich, well-draining soil. Amend your soil with compost or well-rotted manure to improve its fertility and drainage if needed. Unlike some other hydrangeas, the flower color of H. arborescens is not affected by soil pH.
Planting: Dig a hole that’s about twice as wide and just as deep as the root ball of your plant. Place the plant in the hole so that the top of the root ball is level with or slightly above the surrounding soil. Backfill with the excavated soil, firming it gently around the root ball.
Watering: After planting, water thoroughly. H. arborescens likes consistent moisture, so water regularly, especially during dry periods. However, avoid waterlogging the soil.
Mulching: Apply a layer of mulch around the base of the plant to help conserve moisture and suppress weeds.
Pruning: Hydrangea arborescens blooms on new wood, so it should be pruned in late winter or early spring before new growth begins. Pruning encourages a bushier growth and larger blooms. You can cut the stems back to within a few inches of the ground.
Fertilizing: You can apply a slow-release, balanced fertilizer in late winter to promote growth and blooming. However, be careful not to over-fertilize, as this can lead to more leaves but fewer blooms.
Pest and Disease Management: Keep an eye out for common hydrangea pests like aphids and spider mites. Powdery mildew can also be an issue. Most of these can be managed with regular observation and appropriate treatments as needed.
Garden Examples
Recommended Guides
123RF Stock Photo, Shutterstock
Guide Information
| Hardiness |
3 - 8 |
|---|---|
| Heat Zones |
1 - 9 |
| Climate Zones | 1, 1A, 1B, 2, 2A, 2B, 3, 3A, 3B, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, A3 |
| Plant Type | Shrubs |
| Genus | Hydrangea |
| Exposure | Full Sun, Partial Sun |
| Season of Interest |
Summer (Early, Mid, Late) Fall |
| Height |
3' - 6' (90cm - 180cm) |
| Spread |
3' - 6' (90cm - 180cm) |
| Maintenance | Low |
| Water Needs | Average |
| Soil Type | Clay, Loam, Sand |
| Soil pH | Acid, Neutral |
| Soil Drainage | Moist but Well-Drained, Well-Drained |
| Characteristics | Dried Arrangements, Cut Flowers, Showy |
| Native Plants | Alabama, Arkansas, Connecticut, Delaware, Florida, Georgia, Illinois, Indiana, Kansas, Kentucky, Louisiana, Maryland, Massachusetts, Midwest, Mississippi, Missouri, New Jersey, New York, North Carolina, Northeast, Ohio, Oklahoma, Pennsylvania, South Carolina, Southeast, Southwest, Tennessee, United States, Virginia, West Virginia |
| Attracts | Bees, Butterflies |
| Landscaping Ideas | Beds And Borders, Hedges And Screens, Patio And Containers |
| Garden Styles | City and Courtyard, Informal and Cottage, Traditional Garden |
