Hydrangea Section Macrophyllae Cultivars N–O

'Nachtigall'

(Teller Series, introduced 1979) Flowers tending strongly towards blue, dark royal blue on acidic soil to violet or occasionally dark pink on alkaline. Vigorous, with strong shoots; height to 1.5 m. Not the hardiest, warranting shade and shelter (Foster 2023; van Gelderen & van Gelderen 2004). From a New Zealand perspective, where hardiness is less of an issue, Church (2007) goes as far as saying ‘My favourite blue lacecap […] even looks good in winter with a mass of strong yellow stems’ and finds it tolerant of full sun and coastal exposure. From the same very successful cross as ‘Blaumeise’ and ‘Eisvogel’: (‘Möwe’ × ‘Glärnisch’) × (‘Bodensee’ × ‘Enziandom’) (Hempel, Hohe & Tränkner 2018).

Hydrangea 'Nachtigall' tends towards blue in flower, sometimes in very intense shades. Image Maurice Foster.

'Nadeshiko-gaku'

Sterile flowers with toothed sepals, white or with a faint blue/pink wash; fertile flowers blue/pink; height around 1.5 m, Japanese origin (Sous Un Arbre Perché 2025). Leaves relatively narrow, leading to some having speculated that it belongs in H. serrata, but both the International Register (Association Shamrock 2022) and Japanese sources list it as pure H. macrophylla. A very pretty lacecap with a different ‘look’ in the garden.

Blue or pink fertile flowers of Hydrangea macrophylla 'Nadeshiko-gaku' contrast nicely with the much paler or white sterile flowers (Darley Park, Derby, UK; 28 August 2024) Image Julian Sutton.

Hydrangea macrophylla 'Nadeshiko-gaku' has a distinctive garden presence (Darley Park, Derby, UK; 28 August 2024) Image Julian Sutton.

'Nanping'

(China City and Sturdy Series) Sterile flowers lilac / pale pink; fertile flowers pigmented; upright habit to 1.2 m. Selected 1993 by C.P. Eveleens of Koninklijke Handelskwekerij, The Netherlands; protected by European Plant Breeders’ Rights (Hydrangea Derby 2024; Promesse de Fleurs 2024; Association Shamrock 2022).

Hydrangea 'Nanping' in the Shamrock Hydrangea Collection, Varengeville-sur-Mer, France (10 August 2023). Image Jack Aldridge.

'Nehyosh'

Sterile flowers pale lilac/pink, fertile flowers pigmented. Leaves variegated, with a broad yellow margin; height about 1.5 m. Selected 2006 by Rein & Mark Bulk, the Netherlands; rarely offered for sale today. (Royal Horticultural Society 2024; Cotswold Garden Flowers 2024; Association Shamrock 2022)

'New Wave'

Sterile flowers pale blue / pale pink, fertile flowers pigmented. Leaves variegated, with a broad yellow margin, green centre, and sometimes also a thin white zone; height 1–1.5 m; does not scorch in sun for the raiser, but light shade might be wise. A sport of ‘Lemon Wave’ selected before 2010 by Cistus Nursery, Oregon (Far Reaches Farm 2024; Plant Lust 2024; Association Shamrock 2022). Vivid, and not to everyone’s taste: ‘for those who lust for the over-the-top, flamboyant, gaudiness that only the most outrageous variegation can provide, fear not your soulmate has found its way to you’ (Far Reaches Farm 2024).

'Niedersachsen'

Flowers with entire, narrow-based sepals, blue / clear pink, blueing readily. Vigorous growth, height to 1.5 m or more; flowers last best in some shade. An old European cultivar still very much in the nursery trade, introduced 1913 by German breeder Wintergalen (Haworth-Booth 1984; Hydrangea Derby 2024; van Gelderen & van Gelderen 2004; Association Shamrock 2022). Niedersachsen, NW Germany, is known in English as Lower Saxony.

Hydrangea 'Niedersachsen': ageing flowers retain their colour well. (East Ruston Old Vicarage, Norfolk, UK; 19 October 2024) Image Julian Sutton.

Hydrangea 'Niedersachsen' is an old European mophead still much grown. The narrow sepal bases are apparent in this image (Darley Park, Derby, UK; 28 August 2023). Image Julian Sutton.

Hydrangea 'Niedersachsen', a vigorous grower (Darley Park, Derby, UK; 28 August 2023) Image Julian Sutton.

Hydrangea 'Niedersachsen' in pale blue mode (Savill Garden, Surrey, UK; 24 June 2024). Image Julian Sutton.

'Nigra'

Flowers with narrow, non-overlapping sepals, blue/pink, in small, initially dense heads, loosening as pedicels lengthen. Stems dark purple to black, often weak; pedicels red; height to 2 m (Church 2007; Lawson-Hall & Rothera 1995; van Gelderen & van Gelderen 2004). For many years the stem colour was a reason to grow this inferior plant, but it has now been thoroughly superseded. Mallet (2012) finds it especially drought tolerant in northern France, and suspects that this may also be true of other black stemmed cultivars.

Black stemmed mopheads have been in Western gardens since the 19th century, under a range of botanical names, only the commonest ones shown above. They were certainly in the European nursery trade by 1870 (Carrière 1880). We have to assume that they were sent from Japanese or Chinese cultivation, but detailed evidence seems lacking. All these are today labelled H. ‘Nigra’, although there seem to be several related but genetically distinct clones in circulation (Reed & Rinehart 2007).

Ernest Wilson is often said to have introduced this plant to the West, one reference (van Gelderen & van Gelderen 2004) going so far as claiming that he ‘imported it from China to the United States […] in 1853’, 23 years before his birth. Sceptical about this from the start, we have been able to find no trace in Wilson’s writings of any claim to have introduced it personally. The idea may stem from a misreading of Wilson (1923), under H. macrophylla f. mandschurica: a mention of ‘No. 5285’ looks very like one of his own collector’s numbers, but is in fact an Arnold Arboretum accession number (dated 1902, from the Veitch nursery, apparently now lost – Arnold Arboretum 2024).

Hydrangea 'Nigra' in autumn (Avenue Cottage, Ashprington, Devon, UK; 17 October 2023). Image Julian Sutton.

Hydrangea 'Nigra' has black stems (private garden, Ayrshire, UK; 24 August 2023). Image Julian Sutton.

Hydrangea 'Nigra' (private garden, Argyll & Bute, UK; 22 August 2023). Image Julian Sutton.

Hydrangea 'Nigra' has a poor habit even in the hands of experienced hydrangea growers. Nowadays there are better black-stemmed cultivars (private garden, Ayrshire, UK; 24 August 2023). Image Julian Sutton.

'Niji'

Sterile flowers bluer towards the sepal base/centre, pinker towards the apex/margins, the precise shades varying with soil; fertile flowers tend towards blue/purple. A smaller plant not exceeding 1 m, Maurice Foster recommends it for pot or patio where the unusual colour effect can be appreciated close–up (Foster 2023; Sous Un Arbre Perché 2024; van Gelderen & van Gelderen 2004). Origin Japanese, credited to Masaru Inaba (Association Shamrock 2022). Niji translates as ‘rainbow’.

'Nikko Blue'

Flowers with entire sepals, light blue/pink but tending towards blue, in large heads over a long season; remontant. Stems rather weak, height to 1.5 m; less hardy than ‘All Summer Beauty’ or ‘Bailmer’ (ENDLESS SUMMER®), to USDA Zone 6 only. Perhaps originally from Japan. (Boebel 2011; Church 2007; van Gelderen & van Gelderen 2004; Missouri Botanical Garden 2024; Association Shamrock 2022)

Hydrangea 'Nikko Blue' has large inflorescences; it is particularly attractive when light blue (Arboretum Het Leen Eeklo, Belgium – 9 July 2006). Image © Jan De Langhe.

Newly opened flowers of Hydrangea 'Nikko Blue' (Arboretum Het Leen Eeklo, Belgium – 3 July 2005). Image © Jan De Langhe.

Hydrangea 'Nikko Blue' at Arboretum Het Leen Eeklo, Belgium (9 July 2006). Image © Jan De Langhe.

Hydrangea 'Nikko Blue', although tending towards blue, is capable of flowering pink (Morton Arboretum, Illinois). Image Jeff Franklin, Courtesy of The Morton Arboretum.

Hydrangea 'Nikko Blue', a long flowering remontant cultivar: its stems can be rather weak (Morton Arboretum, Illinois). Image Jeff Franklin, Courtesy of The Morton Arboretum.

Hydrangea 'Nikko Blue' in autumn (Morton Arboretum, Illinois). Image John Hagstrom, Courtesy of The Morton Arboretum.

'Odoriko-amacha'

Sterile flowers white, ageing pink, a striking contrast with the strong blue / pinkish fertile flowers. Vigorous, to about 1.5 m height and spread, with leaves intermediate in size between typical H. serrata and H. macrophylla. Usually listed under H. serrata, but widely presumed to be a hybrid. Selected before 1960 by Takeomi Yamamoto, Japan (Foster 2023; Hydrangea Derby 2024; van Gelderen & van Gelderen 2004; Association Shamrock 2022). Odoriko translates as ‘Dancing Girl’, amacha is the tea made from H. serrata leaves.

Hydrangea 'Odoriko-amacha' looking very effective with blue fertile flowers on an acidic soil (Sir Harold Hillier Gardens, Hampshire, UK; 23 July 2023). Image Jack Aldridge.

Hydrangea 'Odoriko-amacha' is thought to be an H. macrophylla × serrata hybrid (White House Farm, Kent, UK; 12 July 2023). Image Julian Sutton.

The white sterile flowers of Hydrangea 'Odoriko-amacha' make a good contrast with the pigmented fertile ones (White House Farm, Kent, UK; 12 July 2023). Image Julian Sutton.

Hydrangea 'Odoriko-amacha' at the pinkish end of its colour range (Darley Park, Derby, UK; 28 August 2023). Image Julian Sutton.

Hydrangea 'Odoriko-amacha' is a vigorous, spreading cultivar, shown here before the pigmented fertile flowers have opened (Savill Garden, Surrey, UK; 24 June 2024). Image Julian Sutton.

Sterile flowers of Hydrangea 'Odoriko-amacha' eventually age pink (Savill Garden, Surrey, UK; 31 October 2024). Image Tom Christian.

Hydrangea 'Odoriko-amacha' can look very attractive well into autumn (Savill Garden, Surrey, UK; 31 October 2024). Image Tom Christian.

'Opri310'

Sterile flowers blue/pink, ageing pink or purple; sterile flowers pigmented; abundant, early flowering claimed. Dense habit, height to 1.2 m. Selected before 1980 by Belgian plantsman Harry Van Trier; named for his niece, and for nurseryman colleague Jan Oprins’ daughter. Unusually among H. serrata cultivars a mass-market success; protected by European plant breeders’ rights. (SAPHO 2022; Association Shamrock 2022).

Hydrangea serrata 'Opri310' (VEERLE) has been a mass-market success, unusually in this species. Image Maurice Foster.

Hydrangea serrata 'Opri310' (VEERLE) in pink mode (16 June 2025). Image Rowan Griffiths.

Purple ageing flowers of Hydrangea serrata 'Opri310' (VEERLE). (Private garden, Argyll & Bute, UK; 22 August 2023). Image Julian Sutton.

'Oregon Pride'

Flowers with serrate, overlapping sepals, tending strongly to purple shades. Stems stout, deep purple- or red-black, height about 1.5 m. A dark-stemmed sport on ‘Merritt’s Supreme’ selected in Oregon around 1975. Reports of the raiser vary, the International Register crediting Theresa Yock (Church 2007; van Gelderen & van Gelderen 2004; Hydrangeas Plus 2024; Association Shamrock 2022)

Hydrangea 'Oregon Pride' in the light shade of the lath house at the JC Raulston Arboretum, North Carolina (19 June 2017). Image Bob Hauver / JC Raulston Arboretum.

Hydrangea 'Oregon Pride' tends strongly towards purple in flower (JC Raulston Arboretum, North Carolina; 25 May 2021). Image Ira Tucker / The JC Raulston Arboretum.

'Otaksa'

From a Western point of view ‘Otaksa’ is one of the founding mophead cultivars, along with plants such as ‘Joseph Banks’ and ‘Rosea’, mere samples of what was being grown in Japanese and Chinese gardens between the mid-18th and mid-19th centuries. Philipp von Siebold encountered ‘Otaksa’ in a Japanese temple garden, named it (albeit in garbled form) for his lover Taki Kusumoto, and grew it in his Deijima garden. It seems not to have been brought to Europe until around 1862, following Siebold’s return to Japan. Initially very popular in Europe, it became rare with the proliferation of 20th century cultivars, and has been confused with ‘Joseph Banks’ and other old mopheads. There are generally similar plants in Japan today which are more common than ‘Otaksa’, differing in size and hardiness (Mallet 1994).

Flowers with entire sepals, light blue / light pink, in hemispherical heads. Height from about 1.2 m to as much as 2.5 m in warm climates. Leaves glossy, strongly dentate; stems rather weak. (Bean 1981; Church 2007; van Gelderen & van Gelderen 2004; Mallet, Mallet & van Trier 1992; Association Shamrock 2022)

Hydrangea macrophylla 'Otaksa', a Japanese plant which from a European perspective is one of the founding mophead cultivars (private garden, Ayrshire, UK; 24 August 2023). Image Julian Sutton.