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Mountain Hydrangea
Hydrangea serrata 'Blue Billow'

Family: Hydrangeaceae (hy-drain-jee-AY-see-ee) (Info)
Genus: Hydrangea (hy-DRAIN-juh) (Info)
Species: serrata (sair-AY-tuh) (Info)
Cultivar: Blue Billow
» View all varieties of Hydrangeas

Height:

36-48 in. (90-120 cm)

Spacing:

4-6 ft. (1.2-1.8 m)

Hardiness:

USDA Zone 5a: to -28.8 C (-20 F)

USDA Zone 5b: to -26.1 C (-15 F)

USDA Zone 6a: to -23.3 C (-10 F)

USDA Zone 6b: to -20.5 C (-5 F)

USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

USDA Zone 8a: to -12.2 C (10 F)

Sun Exposure:

Sun to Partial Shade

Danger:

Unknown - Tell us

Bloom Color:

Light Blue

Bloom Time:

Mid Summer

Late Summer/Early Fall

Foliage:

Deciduous

Other details:

This plant is attractive to bees, butterflies and/or birds

Average Water Needs; Water regularly; do not overwater

Requires consistently moist soil; do not let dry out between waterings

Soil pH requirements:

5.6 to 6.0 (acidic)

6.1 to 6.5 (mildly acidic)

Patent Information:

Unknown - Tell us

Propagation Methods:

By dividing the rootball

From softwood cuttings

From semi-hardwood cuttings

Seed Collecting:

N/A: plant does not set seed, flowers are sterile, or plants will not come true from seed

Regional

This plant has been said to grow in the following regions:

Marietta, Georgia

Saint Joseph, Illinois

Baltimore, Maryland

Catonsville, Maryland

Olney, Maryland

Roslindale, Massachusetts

Horton, Michigan

Warren, Michigan

Colts Neck, New Jersey

Mount Laurel, New Jersey

Tonawanda, New York

Broken Arrow, Oklahoma

Atlanta, Texas

show all

Gardeners' Notes:

5
positives
1
neutral
0
negatives
RatingContent
Positive

On Jun 14, 2014, RemyO from Tonawanda, NY (Zone 6b) wrote:

After a very long colder than normal winter here in zone 6, it is covered in flower buds.

Positive

On Jun 18, 2012, NewMerciesFarm from HADLYME, CT wrote:

This is a great plant to appreciate in the shade in the dog days of July. In the right light the blue is electric and visitors are always drawn to the plant.

While all the US vendors refer to the species as serrata, Van Gelderen's Encylopedia of Hydrangeas lists it as Hydrangea Macrophylla (lacecap group) v. Blue Billow. Can anyone illuminate this point?

Positive

On Sep 27, 2011, rkwright85 from Horton, MI (Zone 5b) wrote:

Has been a strong grower and flowers well for me. I live in southern MI (zone 5b) and have it planted on the east side of my house for some winter protection. May need frequent watering if exposed to very much sun or wind.

Positive

On Jun 7, 2009, gardeneve from Roslindale, MA wrote:

This hydrangea is my best bloomer--no problems at all with later winter freezing of buds. The blue is so intense and the flowers last a long time. However it has not gotten as big as I expected--three years in my garden and it's still only a couple of feet tall (about 4 feet wide).

Positive

On Mar 22, 2007, Kristi_L from Kalamazoo, MI wrote:

Does beautifully planted facing east with full sun until noon near the faucet so it gets plenty of moisture.

Neutral

On Jan 20, 2003, lupinelover from Grove City, OH (Zone 6a) wrote:

The buds are hardier than most cultivars, making it more likely to bloom in marginal areas. A spreading growth habit. Flowers are deep blue with dark centers.