New Zealand hay fever and grass pollen season
New Zealand's grass pollen season runs from November to January. It starts in mid-November in Auckland and reaches its peak a little later the further south you go, around Christmas in Canterbury and Southland. In Auckland it started between 8 and 17 November in all three counted seasons and ended between 27 December and 1 February (Newnham et al. 2025).
Auckland
| Season | Start | End | Season total (grains/m³) |
|---|---|---|---|
| 1988/89 | 17 Nov | 27 Dec | 576-685 |
| 1989/90 | 8 Nov | 1 Feb | 1,169 |
| 2023/24 | 16 Nov | 31 Jan | 862 |
Source: Newnham et al. 2025, Table 2. In the La Niña summer the season lasted 41 days, against 86 and 77 days in the other two. Peaks often followed rainy days by several days. Grass is about 44 % of Auckland's yearly airborne pollen (Haberle et al. 2014).
The rest of the country
The only multi-city count is a 1988-1993 survey, one season per site. It showed the season starting later the further south a site is (Newnham 2022):
| Place | Peak | What the count showed |
|---|---|---|
| Palmerston North | about mid-December | a big season, more than 25 days above 50 grains/m³ |
| Christchurch | about late December | season total 783; highest day 45 |
| Dunedin | late December to mid-January | season total about 1,000 |
| Gore (rural) | about late December | season total 11,910 and a highest day of 2,005 (a farmland site with a low trap) |
Source: Medek et al. 2016 (values read from its figures are approximate). These are published counts, not SkyPollen data. Grass is about 52 % of Christchurch's and 26 % of Dunedin's yearly pollen (Haberle et al. 2014).
Which grasses
New Zealand's hay fever grasses are introduced pasture grasses: tall fescue was the most widespread in the national survey, with ryegrass, cocksfoot, Yorkshire fog, sweet vernal, timothy and others (Newnham 1995; Newnham 2022).
On the SkyPollen map
The smoke map now covers New Zealand: wind, smoke from the Copernicus forecast on days there is any, and NASA fire hotspots. SkyPollen has no daily pollen level for New Zealand yet: no openly licensed daily count exists to check a model against.
Sources
- Newnham RM, et al. Does the ENSO cycle impact the grass pollen season in Auckland, New Zealand? Aerobiology 2025;3:8. doi:10.3390/aerobiology3030008 (CC BY 4.0)
- Newnham RM. Monitoring airborne pollen in New Zealand. J R Soc N Z 2022;52:192-211. doi:10.1080/03036758.2021.1967414
- Medek DE, et al. Regional and seasonal variation in airborne grass pollen levels between cities of Australia and New Zealand. Aerobiologia 2016;32:289-302. doi:10.1007/s10453-015-9399-x
- Haberle SG, et al. The macroecology of airborne pollen in Australian and New Zealand urban areas. PLoS ONE 2014;9:e97925. doi:10.1371/journal.pone.0097925