Wahlenbergia congesta
Common names
harebell
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Herbs - Dicotyledons other than Composites
Flower colours
Blue, White
Detailed description
Compact, mat-forming, predominantly autogamous perennial herb producing numerous close-set rosulate tufts of glossy glabrous, dark green to yellow-green leaves and subsessile white flowers. Petiole 1.5–2 mm, narrow, rather thin. Leaves 8–25 mm, dark green, yellow-green or reddish-green, orbicular, spathulate, margins shallowly crenate-serrate, undulate or flat, narrowed to petiole. Scape solitary arising from centre of each rosette, 10–20 mm long when flowering, elongating up to 50 mm long in fruit. Flowers solitary, terminal, erect, white or faintly tinged blue, 12–15 mm diameter. Calyx lobes 2 × 1 mm wide at base, triangular. Corolla 9–12 mm long, rotate-campanulate to funnelform, tube bowl-shaped, 4 × 5 mm, lobes 7–8 × 5 mm, ovate, obtuse. Capsule 3–6 mm diameter, globular. Seeds glossy brown, ellipsoid.
Similar taxa
None. The coastal habitat, compact, mat forming growth form, and small globose capsule readily distinguish Wahlenbergia congesta from the other rosulate New Zealand species of the genus. Petterson (1997) recognised two subspecies (subsp. congesta and subsp. haastii) within W. congesta. Her subsp. haastii is said to differ from subsp. congesta by having smaller capsules (3 mm cf. up to 6 mm diameter in subsp. congesta) and funnelform rather than rotate-campanulate flowers. These are distinctions which on occasion can be seen in other populations that she had treated as subsp. congesta. Petterson (1997) also argued that there was an ecological distinction, with subsp. haastii rowing only on schist sand—however, this geological difference is apparent only because, in the range where subsp. haastii happens to grow, the beaches are made up primarily of the local rock type—schist. In cultivation the characters she used are soon lost, suggesting that irrespective of substrate there is no genetic or ecological basis to warrant continued recognition of this subspecies.
Distribution
Endemic. New Zealand: South Island (North-west Nelson coastline south to northern Fiordland and also along portions of the northern Foveaux Strait coastline).
Habitat
Coastal on rocky bluffs, cliff faces, ledges, beaches (cobble and sand), sand dunes and in low turf overlying seepages. Usually found in the most exposed sites where constant wind and salt blast reduces competition from taller plants.
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2023 | At Risk – Declining | Qualifiers: Sp, DPS, DPT
Threats
A widespread at times locally common, biologically sparse and somewhat disjunct species. It is possible that some populations particularly those within dune fields are at risk, are declining or have gone extinct but there is as yet have no clear evidence for this.
Detailed taxonomy
Family
Synonyms
Wahlenbergia congesta (Cheeseman) N.E.Br. subsp. congesta, Wahlenbergia congesta subsp. haastii J.A.Petterson, Wahlenbergia morganii Petrie, Wahlenbergia saxicola var. congesta Cheeseman
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
November–February
Fruiting
December–April
Propagation technique
Easily grown from rooted pieces—best kept in a pot and frequently repotted with fresh soil to keep it going. use free draining soil mixed with plenty of sand. Does not like to dry out to much and does best in a sunny situation.
Other information
Where To Buy
Not commercially available.
Plant of the Month
This plant has been featured as a Plant of the Month – see Trilepidea: NZPCN newsletter for December 2016 for the full story.
Etymology
wahlenbergia: Named in honour of Wahlenberg, a Swedish botanist and author of A Botany of Lapland.
congesta: Crowded
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.
WAHCON
Chromosome number
2n = 36
Previous conservation statuses
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | At Risk – Declining | Qualifiers: Sp
2012 | At Risk – Naturally Uncommon | Qualifiers: Sp
2009 | At Risk – Naturally Uncommon | Qualifiers: DP
2004 | Sparse
Referencing and citations
References and further reading
Petterson JA. 1997. Revision of the genus Wahlenbergia (Campanulaceae) in New Zealand. New Zealand Journal of Botanv 35(1): 9–54. https://doi.org/10.1080/0028825X.1997.10410669.
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange (22 October 2006). Description adapted from Petterson (1997).
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Wahlenbergia congesta Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/wahlenbergia-congesta/ (Date website was queried)