Very Strong El Niño 2026/27: What It Means for New Zealand Gardens

29 September 2026

New Zealand gardeners are being warned to prepare for an unusually strong El Niño over the coming spring and summer, with increased wind, changing rainfall patterns and greater temperature swings likely to affect growing conditions around the country.

Earth Sciences New Zealand says the current El Niño is continuing to strengthen and may become the strongest El Niño on record. The organisation gives a 100% chance of El Niño continuing through the remainder of 2026 and into early 2027.

El Niño occurs when parts of the central and eastern tropical Pacific become significantly warmer than normal, altering weather patterns across the Pacific.

For New Zealand, one of the most noticeable effects is typically a shift towards stronger and more frequent winds from the west and southwest.

A Windier Spring and Summer

Earth Sciences New Zealand expects El Niño to bring periods of active westerly weather, unusually windy conditions and greater temperature variability during spring.

These conditions can have a significant impact on gardens.

Strong winds increase moisture loss from both plants and soil, while young trees, tall perennials, vegetables and newly emerging spring growth can be more vulnerable to physical damage.

Gardeners may also notice larger swings between warm and cool conditions rather than consistently warm spring weather.

Some Regions Likely to Become Drier

Rainfall is also expected to vary considerably across the country.

For Northland, Auckland, Waikato and Bay of Plenty, rainfall during spring is currently most likely to be below normal.

The same applies to Gisborne, Hawke's Bay and Wairarapa, where warmer conditions, periods of high winds and lower soil moisture are also expected.

Parts of the upper South Island, Canterbury and eastern Otago also have an increased chance of below-normal rainfall or soil moisture.

This could mean gardens begin drying earlier than usual as spring progresses into summer, particularly in exposed locations.

The situation is quite different on the West Coast and parts of the lower South Island, where rainfall is expected to be above normal and periods of heavy rain and stormy weather are more likely.

What Does This Mean for Gardeners?

For many New Zealand gardeners, the main issue over the next few months may be managing the combination of wind and declining soil moisture.

A few simple preparations now could help:

• Mulch garden beds while spring soil still contains good moisture.

• Check stakes and supports around young trees and tall plants.

• Water deeply when required rather than relying on frequent light watering.

• Avoid applying fertiliser to severely dry or drought-stressed plants.

• Keep an eye on containers and hanging baskets, which can dry rapidly in strong winds.

Gardeners in wetter western areas may instead need to pay more attention to drainage, waterlogging and fungal disease.

An Unusual Growing Season Ahead

El Niño does not mean every part of New Zealand will experience drought or extreme weather, and seasonal forecasts cannot predict individual weather events months in advance.

However, the strength of the developing event means its influence is expected to be significant through the 2026/27 growing season.

For home gardeners, this spring may be a good time to prepare for a season where wind, water and rapidly changing conditions play a larger role than usual.