Smooth Hydrangea

Hydrangea arborescens

A very fast growing, open, typically suckering shrub reaching around 5 feet or more that is native to moist woods of the eastern U.S. ( from southeast Kansas to northern Indiana to southeast Iowa to central New York State to Massachusetts; south to eastern Oklahoma to northern Louisiana to far northwest Florida to South Carolina ). It is endangered in Kansas and New York State. Some records include: largest on record - 12 x 20 feet.
The broadly oval, pointed leaves, up to 9 x 7 inches are lush deep green. The foliage turns pale yellow during late fall.
The showy, very profuse creamy white flowers are borne in flat flowerheads up to 12 inches across in summer. The flowers attract hummingbirds and butterflies.
Hardy zones 2 to 8b on moist soil in partial shade on fertile, moist, well drained soil. Extremely adaptable, it is hardy from Alberta to northern Florida. Some of the hardiest seed source even survives in south-central and southeastern Alaska. The best flower displays are on plants that are cut back to 8 inches from ground level in March for vigor. In zones 2 and 3, it may die back completely to the ground during the winter, re-emerging during the following the spring and blooming the very same summer.
Smooth Hydrangea is not generally eaten by deer.

* photos taken on June 23 2013 @ U.S. National Arboretum, DC

* photos taken on Aug 4 2013 in Bayfield, Ontario

* photo taken on July 28 2015 in Marine City, MI

* photo taken on June 5 2019 in Columbia, MD

* photo taken on July 14 2019 in Blyth, ON

* photo taken on July 12 2019 in Bayfield, ON

* photo taken on Nov 5 2024 in Columbia, MD

'Annabelle'
Similar in size to H. arborescens, reaching up to 5 feet if grown as a cut back perennial.
The leaves on cut back plants are unusually large, up to 15 inches in length and are bright green, turning pale yellow during autumn.
Pure white flowers borne in huge flowerheads up to 1 foot across.
It thrives even in Alberta's harsh climate however growing much smaller, only around 3 x 5 feet in 5 years. Plants may live 50 years or more.

* photos of unknown internet source


* photos taken on Aug 2 2012 in Bayfield, ON

* photos taken on June 23 2013 @ U.S. National Arboretum, DC

* photos taken on Aug 1 2013 in Stratford, Ontario

* photo of unknown internet source

* photo taken on June 24 2014 in Columbia, MD

* photo taken on June 9 2015 in Columbia, MD

* photos taken on July 27 2015 in Bayfield, ON

* photo taken on July 25 2015 @ Niagara-on-the-Lake, Ontario

* historical archive photo

* photo taken on Jun 20 2016 in Columbia, MD

* photo taken on July 16 2016 in Bayfield, ON

* photo taken on July 17 2016 in Blyth, ON

* photos taken on Jul 17 2017 in Ottawa, ON

* photo taken on Aug 5 2017 @ Brookside Gardens, Wheaton, MD

* photo taken on July 13 2018 in Bayfield, ON

* photos taken on July 17 2018 @ Leacock Museum in Orillia, ON

* photo taken on June 4 2019 @ Howard Comm. College, Columbia, MD

* photos taken on June 7 2019 @ Univ. of Maryland, College Park

* photos taken on July 12 2019 in Bayfield, ON

* photo taken on June 15 2021 in Columbia, MD

* photos taken on Aug 22 2021 in Bayfield, ON

* photo taken on July 9 2022 in Bayfield, ON

* photos taken on July 7 2023 @ Bayfield, ON

* photo taken on June 3 2024 in Columbia, MD

'Bella Anna'
Very similar to 'Invincibelle Spirit' but slightly smaller, growing at a moderate rate to 6 x 6 ( rarely over 5 ) feet.
The foliage is deep green turning golden-yellow during autumn.
The large, deep pink, mophead flower clusters are borne on old and new wood during summer and autumn.
Hardy zones 3 to 8.

* photos taken on June 16 2013 in Columbia, MD

* photo taken on June 16 2014 in Columbia, MD

* photo taken on July 1 2016 in Columbia, MD

* photos taken on June 3 2017 in Columbia, MD

* photos taken on June 10 2017 in Columbia, MD

* photo taken on Aug 8 2017 in Columbia, MD

* photos taken on June 5 2018 in Columbia, MD

* photo taken on June 17 2018 in Columbia, MD

* photos taken on June 26 2018 in Columbia, MD

* photos taken on June 18 2019 in Columbia, MD

* photos taken on June 14 2020 in Columbia, MD

* photo taken on Aug 27 2020 in Columbia, MD

* photos taken on June 23 2021 in Columbia, MD

* photos taken on June 15 2022 in Columbia, MD

* photos taken on June 6 2023 in Columbia, MD

* photo taken on June 19 2023 @ Hershey Gardens, Hershey, PA

* photos taken on June 9 2024 in Columbia, MD

'Golden Annabelle'
Similar to 'Annabelle' except for having foliage that is broadly and boldly margined golden-yellow.

'Grandiflora' ( Snowhill Hydrangea )
Pure white sterile flowers in mop heads up to 8 inches across.
Plants sucker forming clumps up to 20 feet across.

* historic archive photos

'Haas Halo'
Fast growing and upright, reaching up to 7 x 7 feet, bearing huge lacecap flower clusters, up to 14 inches wide, atop sturdy stems. The white flower clusters are the largest of any Hydrangea. The ovate leaves average 6.5 x 5 inches in size.
Hardy zones 3+, it is more drought tolerant than most H. arborescens.

* photos taken on July 17 2017 in Ottawa, ON

* photos taken on Aug 1 2022 in Brookside Gardens, Wheaton, MD

* photo taken on May 30 2024 in Ellicott City, MD

* photos taken on July 10 2024 @ Brookside Gardens, Wheaton, MD

* photo taken on Oct 31 2024 in Ellicott City, MD

* patent photo

'Hayes Starburst'
A compact form, reaching up to 4 x 5 feet. It was discovered by Hayes Jackson growing self sown in his Anniston, Alabama garden. It can be lax and sometimes nearly trailing in habit growing in shade.
The deeply-toothed foliage is deep green.
The rounded, dome-shaped flower clusters, up to 8 inches wide, are densely packed with sterile, star-shaped, double white flowers. The flowers last over a very long period from early summer into early autumn.
hardy zones 3 to 8.

* photos taken on Aug 24 2017 @ U.S. Botanic Garden, Wash. DC.

'Incrediball'
This is the 'Annabelle on Steroids" Hydrangea. It is truly spectacular! The flowers are borne in massive basketball-like flower clusters, up to 1 foot across.
They open lime-green, turning to pure-white then back to greenish-yellow as they fade during autumn. Up to 75 or more flowers may be borne at a time on a plant over a period of 2 months lasting mid-summer into fall. The flowers are borne on massive, thick, sturdy stems and do not flop. Besides having larger blooms, it also blooms much more profusely than 'Annabelle'.
The foliage is luxuriant deep green.
A fast growing, large, mounding shrub, reaching up to 5 x 8 feet, it is recommended to cut this Hydrangea back hard during late winter to enhance blooming.
Hardy zones 3 to 9 in sun or partial shade ( afternoon shade preferred in the south )

* photo taken by Milan Havlis, owner of central Europe's premier plant nursery

* photos taken on July 25 2015 @ Niagara-on-the-Lake, Ontario

* photo taken on Jul 27 2015 in Bayfield, ON

* photo taken on May 27 2017 @ Meadowlark Botanical Gardens, Vienna, VA

* photo taken on Jul 17 2017 in Ottawa, ON

* photo taken on July 16 2018 in Midland, ON

* photo taken on July 14 2019 in Blyth, ON

* photos taken on June 12 2020 in Columbia, MD

* photos taken on June 8 2021 in Columbia, MD

* photo taken on Nov 3 2021 in Columbia, MD

* photo taken on June 6 2022 in Columbia, MD

* photo taken on July 9 2022 in Bayfield, ON

* photo taken on July 6 2022 in Bothwell, ON

* photo taken on July 7 2023 @ Bayfield, ON

* photo taken on Nov 16 2023 in Columbia, MD

* photo taken on Apr 20 2024 in Columbia, MD

* photos taken on June 7 2024 in Columbia, MD

* photos taken on June 20 2024 in Columbia, MD

'Incrediball Blush'
A fast growing, large, mounding shrub, reaching up to 3 x 3 feet in 3 years, eventually to 5 x 8 feet.
The foliage is luxuriant deep green. The leaves are up to 7 x 6 inches in size.
The pale pink flowers are borne in massive basketball-like flower clusters, up to 1 foot across. Up to 75 or more flowers may be borne at a time on a plant over a period of 2 months lasting mid-summer into fall. The flowers are borne on massive, thick, sturdy stems and do not flop.
Hardy zones 3 to 9, it is recommended to cut this Hydrangea back hard during late winter to enhance blooming.

* photos taken on Oct 29 2022 in Columbia, MD

* photo taken on May 7 2024 in Columbia, MD

* photo taken on May 23 2024 in Columbia, MD

* photo taken on May 31 2024 in Columbia, MD

* photos taken on June 7 2024 in Columbia, MD

* photo taken on June 23 2024 in Columbia, MD

* photos taken on Nov 12 2024 in Columbia, MD

* patent photos

'Invincibelle Limetta'
Dense, compact and rounded in habit, reaching up to 2 x 2 feet in 2 years and an eventual maximum size of 4 x 4 feet.
The broadly-ovate leaves, up to 4 x 3 inches in size, are mid-green.
The flowers are lime-green at first, turning ot white. They appear in large, globular flowerheads, up to 8 inches wide, during early to mid summer. The flowers are borne on strong stems and do not flop.
Hardy zones 3 to 8 in full sun to partial shade. It has superior heat tolerance.

* photo taken on June 13 2022 in Columbia, MD

* photo taken on June 24 2022 in Columbia, MD

* photo taken on May 30 2023 in Columbia, MD

* photo taken on June 6 2023 in Columbia, MD

* photo taken on June 14 2023 in Columbia, MD

* photo taken on June 26 2023 in Columbia, MD

* patent photo

'Invincibelle Ruby'
Same as 'Annabelle' but with pink blooms. Sturdy and vigorous, it blooms on new wood and re-blooms until fall frosts. The flowers, lasting 4 months of more, are deep pinkish-red. The flower clusters reach up to 12 inches across. Up to 100 or blooms may be borne on a plant that may reach up to 6 x 6 feet ( average 4 x 5 ) feet in 10 years, eventually more.
The foliage is luxuriant, deep green.
Hardy zones 3 to 9 and heat tolerant. It may become a perennial in zone 3 but plants survive at least as low as -40 F. It thrives from Manitoba south to the Gulf Coast.

* photos taken on June 19 2021 in Ellicott City, MD

'Invincibelle Spirit'
Same as 'Annabelle' but with pink blooms. Sturdy and vigorous, it blooms on new wood and re-blooms until fall frosts. The flowers, lasting 4 months of more, are deep pink in bud, opening to hot pink, then fading to soft pink then finally to green at the end of the bloom cycle. The flower clusters reach up to 12 inches across. Up to 100 or blooms may be borne on a plant that may reach up to 3.3 x 3.3 feet in 2 years, 6 x 6 feet ( average 4 x 5 ) feet in 10 years, eventually up to 8 feet wide.
The foliage is luxuriant, verdant mid-green.
Hardy zones 3 to 9 and heat tolerant. It may become a perennial in zone 3 but plants survive at least as low as -40 F. It thrives from Manitoba south to the Gulf Coast.

* photo taken on June 8 2012 in Howard Co., MD
* photos taken on Aug 3 2012 in London, Ontario

* photo taken on June 30 2013 @ U.S. National Arboretum, DC

* photo taken on June 21 2018 in Columbia, MD

* photo taken on July 14 2019 in Blyth, ON

* photos taken on June 11 2024 in Columbia, MD

'invincibelle Wee White'
Compact and rounded in habit, reaching up to 1.2 x 1.83 feet in 2 years, to 2 x 3.5 feet in 4 years, eventually to 2.5 x 3.5 feet.
The broadly-ovate leaves average 5.3 x 4.2 inches in size. The foliage is mid-green.
The flowers are very pale pink, quickly turing to white. They are borne in dense rounded clusters, up to 4 x 9 inches in size, atop strong stems from early summer until autumn frost.
Hardy zones 3 to 8

* photos taken on June 2 2023 in Columbia, MD

* photo taken on July 2 2023 in Columbia, MD

* photos taken on Aug 2 2023 in Columbia, MD

* photos taken on Oct 27 2023 in Columbia, MD

* photos taken on Nov 11 2023 in Columbia, MD

* photo taken on July 8 2023 in Collingwood, ON

* photo taken on May 16 2024 in Columbia, MD

* photos taken on May 29 2024 in Columbia, MD

* photos taken on June 3 2024 in Columbia, MD

* photos taken on June 20 2024 in Columbia, MD

'Mary Nell'
Reaches up to 6.5 feet in height and forms large colonies up to 9 feet or wider, with large clusters, up to 8 inches wide, of white multisepaled flowers. The blooms last over a long period up to 2 months with some rebloom if deadheaded.
The large leaves are mid-green. It has excellent heat tolerance for a Hydrangea arborescens.

'Mini Mauvette'
A compact, upright form, reaching up to 2.7 x 2.7 feet in 2 years, eventually to 3 x 3 feet.
The foliage is deep green. The broadly-ovate leaves are up to 5 x 3.7 inches in size.
The mauve-pink flowers appear on large clusters, up to 7 inches wide, on sturdy stems. They appear during early summer and often repeat into early autumn.
Hardy zones 3 to 8

* photo taken on July 7 2020 in Elkridge, MD

* photos taken on Aug 1 2023 in Ellicott City, MD

* photo taken on June 18 2023 in Columbia, MD

* photo taken on Nov 17 2023 in Columbia, MD

* photo taken on Apr 22 2024 in Ellicott City, MD

* photos taken on June 20 2024 in Columbia, MD

* photos taken on July 6 2024 in Ellicott City, MD

* photo taken on Aug 13 2024 in Columbia, MD

* patent photos

'Pinky Pollen Ring'
Fast growing and compact, upright and rounded in habit, reaching up to 3 x 3.5 feet in 3 years, eventually to 5 x 5 feet.
The leathery foliage is glossy deep blue-green. The ovate leaves average 3.7 x 2 inches in size.
The flowers are deep pink in bud, opening to pale pink. The flower clusters are up to 5" wide and are borne atop strong stems.
Hardy zones 3 to 8

* photo taken on July 24 2023 in Columbia, MD

* patent photos

subsp 'Radiata' ( Silverleaf Hydrangea )
Foliage is deep green above and silvery-white felted beneath; otherwise identical to species.
It is native to the southern Appalachian Mountains ( eastern Tennessee to western North Carolina; south to northern Georgia ).
Hardy zones 4 to 8a

'Samantha'
A clone originating from subspecies 'Radiata', reaching up to 6 x 6 feet.
The very attractive foliage is deep green above, nearly white beneath.
The foliage turns to bright yellow during autumn.
It is otherwise similar to the species.
Hardy zones 3 to 6, it is unfortunately less heat tolerant than the species and not adapted to non-mountainous parts of the southeast.

'Seaside Serenade'
A vigorous but compact form, reaching up to 2.4 x 1.8 feet in 2 years, eventually to 4 x 4 feet.
The foliage is luxuriant deep green. The ovate leaves are up to 6 x 4.2 inches in size.
The white mophead flowers appear on sturdy stems over a long season on this repeat bloomer. The flattened panicles, up to 4 x 9 inches in size, appear mid-summer into autumn.
Hardy zones 3 to 7

* photo taken on Sep 27 2020 in Elkridge, MD

* patent photo