Climate zones

Occasionally, I receive e-mails from readers who are confused about which gardening or climate zone they live in. Australia has been divided into as many as eight different gardening zones because of the huge variations in temperature and rainfall across our continent. Altitude variations or geographical features within each zone will modify temperatures and rainfall patterns, breaking up the eight zones even further.
To complicate the issue, climate change is resulting in evolving milder winter conditions in some areas and longer, harsher winters in others. Last summer, extreme heat or rain events played havoc with a lot of gardens across Australia, and the extent of further changes related to extreme weather events is impossible for anyone to accurately predict.
However, Australia can be divided into three basic gardening or growing zones; Warm, Cool, and Temperate (as indicated in the diagram below). The zone divisions are based on the types of plants that will grow in a moderately irrigated garden in each zone
Within these basic zones, altitudes and geographical features gardens at higher altitudes will be cooler than those at sea level in adjoining areas. Sea breezes can provide a milder climate for coastal areas than those a few kilometres inland. Gardens where cold air can flow downwards will be less damaged by frost than gardens in valleys or where solid walls block the escape of cold air. These variations are known as local microclimates, and gardeners may have to make minor adjustments to what they can grow each month according to local conditions, and evolving microclimates brought about by climate change.
New Zealand has a more constant climate and can be divided into temperate and cool zones. Frosts do occur, and snow falls on the mountains, but New Zealand is not subject to hot winds from a parched inland. New Zealand is a very suitable place for growing an extensive range of species from Europe, North America, and the cooler parts of Asia.

These are frost free, or may experience some frosts in inland areas during their short winters, and are not suitable for plants that require a defined period of chilling. Warm zones are suited to warmth-loving Australian natives and plants, including fruits and vegetables, from warmer areas of the world. December, January, and February can be too hot for gardening in a lot of warm zones, and some warm zones experience distinct wet and dry periods requiring conventional vegetables and some annuals to be grown at different times to other zones.
The Tropic of Capricorn runs through the northern states of Australia from Rockhampton and Longreach in Queensland, just above Alice Springs in the Northern Territory, and crosses the West Australia coast between Carnarvon and Exmouth. In areas from Rockhampton northwards, tropical coastal conditions allow an entirely different style of gardening, while in drier areas high temperatures and lower water availability make gardening quite a challenge. Winter temperatures in areas within the Tropic of Capricorn can be higher than summer temperatures in some Cool Zones, and common vegetables from temperate areas can only be grown during winter months. Consequently, I have divided this zone into two sub-sections.
Warm zones:
All of Queensland (except for the southern highlands),
Northern Territory,
North coast of NSW above Coffs Harbour,
Northern West Australia,
Northern South Australia.

These are areas where low temperatures occur for long periods. Frosts are common in winter and can continue into spring. Snow occurs in some areas. Cool zones are suitable areas for growing many European, Asian, and North American plants that require a period of winter chilling. Many of the fruits and vegetables we are familiar with come from cooler climates. They, and frost-hardy Australian natives, grow well in Australian cool zones, but frost-tender plants, and plants which require a long period of warmth to flower or fruit are unsuitable for these areas.
Australian cool zones:
All of Tasmania, and the ACT,
Southernmost part of South Australia including Mt Gambier,
Around Albany in Western Australia,
Most of Victoria (except for Melbourne and Benalla areas),
Far south coast of NSW,
NSW tablelands and highlands.
New Zealand cool zones:
The interior of the North Island,
The entire South Island.
(However, within these areas, protected local microclimates along the coast as far south as Christchurch can be regarded as cool temperate areas, extending the planting range.)

These, strictly speaking, are all areas on earth between the Polar Regions and the Tropics of Cancer and Capricorn. Although winter frosts occur in some temperate zones, soil warms quickly in spring. The areas of Australia not listed above can be considered temperate zones, because an extensive range of Australian and New Zealand natives, and decorative plants, vegetables, and fruits from temperate regions around the world can be grown in these areas. January to late February can be too hot for a lot of gardening activity in some Australian temperate zones, but mild autumn weather usually extends from March through May.
Minimum temperatures within metropolitan areas of Sydney, Adelaide and Perth are similar and tend to be slightly higher than those in surrounding areas. Melbourne’s minimum temperature is only slightly lower, and gardeners in Melbourne may find that they can grow many temperate climate plants in protected gardens.
On the North Island of New Zealand, North and South Auckland areas, Hamilton, most of the west coast to just above Wellington, the Bay of Plenty area, and the east coast to Hastings are temperate zones.

7 thoughts on “Climate zones

  1. Hi, Can you please tell me the “climate” for Benarkin North, Queensland ? I believe it is temperate, but not sure. Thanks

    Yes, Keith. You would be wise to follow planting guides for Temperate climate zones. Although you get warm day temperatures in Benarkin, the nights can be very cold from April to September. – Lyn

  2. Some day I would love to see Australians have the same resources that they have in North America (and much of the 1st world for that matter)… serious agricultural resources like :
    – climate zones (including local micro climates) by post code and/or town/suburb name.
    – A proper guide to the expected normal first and last frost dates (especially hard frosts)
    The lack of this information from CSIRO is puzzling, as farming is a primary industry. I can (of course) get details on rainfall and the sort of yearly pattern we are looking at. I can even get the current average soil moisture content for each soil type in my area. However there seems to be NO information at all on when I can expect the temperature to rise enough to plant a given crop in my home garden. Every time I have moved house in SA over the last decade plus, I have had to figure this information out all over again, BY PERSONAL EXPERIENCE. Why?
    The best I can get on starting to plant post frost, is any time from July 1 to August 15…depending on where in SA I live…maybe…but we are expected to figure it all out for ourselves without an official resource that tracks this stuff for us, and provides it to us.
    Every country in the world that takes agriculture seriously has had this specific information available, often tracked and published by their governments (as well as by various private organizations) since the late 1700s (starting in simple Almanacs like th one published by Benjamin Franklin).
    Why are we more than 200 years behind the rest of the world on this? You can get extremely accurate planting zone guides for all of the USA, broken down to very small areas. The lack of this information cripples the efficiency of our farming industry, and to me it is just frustrating. In this era, collecting and recording highly accurate information can all be done with automatic computerized equipment – and send on to a central repository with no human effort needed once a weather station is put in place. Yet we seem to be doing nothing.
    For me, an avid organic gardener in the general Karoonda SA area, it is all very frustrating. It has taken me 3 years just to figure out when I can safely (maybe) sew my spinach, silverbeet, carrots and lettuce… and not have it all do poorly or outright die from frost. it can be aquired in an automated fashion

    I have no idea why you would be told “post frost, is any time from July 1 to August 15”. That’s winter and you live in a cool temperate area. If you use the Cool Climate guide for the colder months, and the Temperate guide for the warmer months, it should suit your area if you get frosts. Microclimates do cause local variations as sites where cold air cannot drain downwards are more likely to have frosts.– Lyn

  3. Hey, I was reading ur artical and it says all of queensland is “worm climate zone” apart from the southern Highlands. I live on Atherton Tablelands in Far North Queenland near Ravenshoe, which happens to be the highest town in Qld. It gets so cold here. I was wondering if its still considered a “worm Area” and what can i grow.
    I have been growing passionfruit for last few years which is doing quite well. I was wondering what other fruit would grow here?

    I go into more detail about climate zones and microclimates in my book, including that places at higher altitudes are cooler. Basically though, if you get chilling in winter, you can grow some fruit plants from temperate areas that need a cold spell for dormancy to produce good fruit. – Lyn

  4. Hi, I am keen to grow some veggies & herbs in my backyard in Exmouth, Western Australia. When is the best time to plant the seeds? I have the following seeds: lettuce, rockets, cherry tomato, baby beets, capsicum, dwarf beans, spring onions, garlic chives and basil. I have two large planters which I plan to (colorbond planter boxes). I have an area in the backyard near the shed which has part shade in the afternoon but I was considering erecting some shadecloth as the weather is very hot at this time of the year. Any advise would be appreciated. Many thanks

    Suzanne, each month I post “what to plant” for each main climate zone so that gardeners will know what to grow. Exmouth is above the Tropic of Capricorn so it falls within the Warm Climate – North of Rockhampton zone. It is too hot now for some vegetables in your zone as many of the vegetables we commonly eat come from cooler northern hemisphere zones, but providing some shade will help. However, you will be able to grow lots of things when the weather gets too cool for other climate zones. If you want to know ahead what to sow when, you will find a full year of when to plant, fertilise, prune, take cuttings, and harvest in my book, ‘Easy Organic Gardening and Moon Planting‘. – Lyn

    See: What to plant in December 2009

  5. when are strawberries in seasion to grow?

    Kartia, strawberries usually produce fruit through winter in sub-tropical climates. After fruiting is finished the plants then put out runners that you can use for propagation. See this post:
    If you don’t have any strawberries growing, it is best to start with some crowns from a reputable nursery. Nurseries sell crowns that are certified free of strawberry virus. You don’t need a lot of crowns to start with as, with a bit of TLC, your plants will produce lots of strong runners to increase your number of plants for the following season. – Lyn

  6. Hello. Could you please tell me if Pink Lady Apples will grow in Morisset NSW post code 2264 and will they need another apple tree near by to produce fruit. Thanking You. Malcolm Pitt
    Hi Malcolm, your question could be of interest to other readers and I’ve answered it in detail Click here. – Lyn

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