Nikko Blue
BOB STEFKO
If you’ve seen large blue hydrangea flowers before, chances are you’ve seen this cultivar. Coming from Japan, 'Nikko Blue' reliably turns blue in home gardens and like the bigleaf species, grows to about 6 feet tall and wide. Plant your 'Nikko Blue' in moist, well-mulched soils in part shade for them to look their best throughout the growing season.
Endless Summer
Endless Summer is often credited for changing the game for hydrangeas with their ability to produce flower buds on old and new growth, unlike the species which produces flower buds only on the previous year’s growth. This ability and hardiness down to Zone 4 has allowed northern gardeners to enjoy the “mophead” blooms of bigleaf hydrangeas without fear of losing buds over winter. Endless Summer grows slightly shorter than the species.
Pop Star
BAILEY NURSERIES
A newer introduction in the Endless Summer line, Pop Star features electric blue lacecap flower heads all summer long on very sturdy stems. These plants are fairly compact, growing to just 3 feet tall and wide at maturity. Pop Star also is very hardy, reliably coming back each spring down to Zone 4.
Blue Enchantress
MONROVIA.COM BY DOREEN WYNJA
Another reblooming blue hydrangea with hardiness to boot, 'Blue Enchantress' grows to a max height and width of about 5 feet, making it a bit more compact than the species. Blooms start out a light sky blue and eventually change to a creamy green.
Blue Jangles
PROVEN WINNERS
From the Let’s Dance series, 'Blue Jangles' is an improvement on color in the reblooming and dwarf categories. Growing to only 3 feet tall and exceptionally compact, this small hydrangea is great for tight spaces and containers.
Starlight
PROVEN WINNERS
Another addition from the Let’s Dance series, 'Starlight' produces gorgeous lacecap flowers. Unlike the traditional mophead look, lacecaps produce flattened flower heads that bloom more sporadically, producing a starry look. It gets up to 4 feet tall and is best grown in Zones 5-9.
Big Daddy
Heading in a totally different direction in terms of size and flower shape, 'Big Daddy' is a large hydrangea, reaching upwards of 6 feet tall and produces huge mophead type flowers. A little more sensitive than most on the list, this gentle giant prefers part shade and constant moisture to maintain its giant flower heads and is only hardy to Zone 6 and higher.
Cape Cod
MONROVIA.COM BY DOREEN WYNJA
Back on the smaller end of the spectrum, 'Cape Cod' is a part of the Seaside Serenade series that combines a small size (about 4 feet tall and wide) and hardiness down to Zone 4. This blue hydrangea is great for in-ground plantings in the north and grow them in pots year-round further south. 'Cape Cod' is a repeat bloomer with two tone blue and white individual flowers, giving it a unique look.
Twist-N-Shout
KRITSADA PANICHGUL
'Twist-N-Shout' combines cold hardiness with a maximum size of 4 feet tall and wide, lacecap style, and repeat blooms. Against the darker, unopened buds, the light blue color of the flower heads really pops, creating a beautiful and eye-catching effect.