Hydrangea macrophylla
Environmental Weed (2024)
Common names
hydrangea
Biostatus
Exotic
Category
Vascular
Structural class
Trees & Shrubs - Dicotyledons
Flower colours
Blue, Violet/Purple
Detailed description
Deciduous rounded shrub to about 2 m tall with suckering habit. Leaves tend to be towards the end of the branches and are ovate and up to about 20 x 15 cm, margins coarsely serrate. Flower head either rounded or flat. Usually composed of sterile flowers (especially in cultivation) but can have fertile flowers in centre. Seed capsule to about 5 mm long.
Similar taxa
Hydrangea is very familiar to New Zealand gardeners, wild material can appear quite different with flat inflorecences containing sterile flowers.
Habitat
Terrestrial. Persistent around old homesteads, near water and on forest margins.
Conservation status
Not applicable
Detailed taxonomy
Family
Hydrangeaceae
Ecology
Flowering
November, December, January, February, March.
Year naturalised
1975
Origin
Japan
Reason for introduction
Ornamental.
Tolerances
Prefers damp shady areas.
Life cycle
Reproduces by suckering, persisting from cultivation and seed. Viable seed can be produced. Dispersed by people and gravity.
Other information
Etymology
hydrangea: From the Greek hydor ‘water’ and aggeion ‘a vessal or vase’, referring to the shape of the seed capsules.
macrophylla: Big leaf
Environmental Weed (2024)
This plant is named in a list of 386 environmental weeds in New Zealand 2024 prepared by DOC. 759 candidate species were considered for inclusion on this new comprehensive list of environmental weeds in New Zealand. The species considered were drawn from published lists of weed species, lists of plants that must be reported or managed by law if observed, existing national and regional programmes and agreements for pest management, and species already managed by the Department of Conservation (DOC). Candidate species were then assessed to see if they were fully naturalised and whether they have more than minor impacts in natural ecosystems. Read the full report here.
NVS code
The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.
HYDMAC
Referencing and citations
References and further reading
Johnson, A. T. and Smith, H. A (1986). Plant Names Simplified: Their pronunciation, derivation and meaning. Landsman Bookshop Ltd: Buckenhill, UK.