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The Australian grow season runs from August through April (give or take a few months, depending on your specific location and situation). This grow calendar will help you with your growing endeavors for the next 7-9 months. It includes averages for day lengths and temperatures to help you get a better idea of what you can expect.

This is an excellent way to help new (and old) growers know how to plan their grow season and best budget their time. Even though it feels early, it is important to start preparations for your grow season now. Happy growing!

The first half of this article covers Eastern, Western, Southern Coasts and Central Australia.

Click here to head to the calendar for northern Oz or go here for the U.S. grow calendars.

East, West, South and Central Oz

A Few Notes:

  • Averages are based on Melbourne, Perth, and Brisbane
  • The hottest days are experienced in the desert or the interior of Australia
  • The Southeastern tip of Australia (including Tasmania) has a temperate climate, meaning it is cooler and wetter than the rest of the country
  • The main difference between the desert (central Australia) and the coast is the fact that it is hotter and dryer. This means growers should simply take care to water their outdoor plants more frequently and in higher quantities.

Make sure to download my free Grow Bible if you’re just starting out

August

Average day length: 10.5 to 11.5 hours
Average temperature: 8 to 18 degrees Celsius

The Desert:
Average day length: 11 to 11.5 hours
Average temperature: 7 to 23 degrees Celsius

buy your seeds

This is the perfect month for preparing for the future grow season. Especially in the warmer regions of the Australian coastline, the worst of the colder weather is soon to be history, and it’s time to prepare your grow area and your plants. It is unlike there will be any frost to worry about any more, meaning you can almost start growing in August.

For that reason, you should order your seeds and begin the germination process as soon as you can. Since the growing season can last for a while in most parts of Australia, a plant that has Sativa dominant genes should do just fine in an outdoor grow setting. Indicas don’t fare as well in the heat that is to come, so be sure you know what you’re getting when you research and order seeds.

Ideally, seedlings will grow somewhere between
20 to 25 degrees Celsius, so unless this month is unseasonably warm, it’s a good idea to start your seedlings indoors and then wait until the temperature rises consistently enough to bring them outside. If you are growing your plants exclusively outdoors, you had better wait a while. While you wait, prep your soil with compost and worms.

If you are planning on cloning, it’s a good idea to begin growing the mother plant this month (ideally indoors). That way you can take the cuttings when it is still early in the grow season.

These outdoor strains are perfect for growing in the warmer Australian climates. Be sure to pick the right seeds for your grow.

September

Average day length: 11.5 to 12.5 hours
Average temperature: 9 to 20 degrees Celsius

The Desert:
Average day length: 11.5 to 12.5 hours
Average temperature: 11 to 27 degrees Celsius

Start sprouting your plants

The risk of frost has dropped even more, especially in the warmer parts of the country. If you haven’t already, you should definitely buy your seeds by now. If you already have them and are prepared with your soil and other necessities, you can safely put your young plants on the windowsill to begin sprouting them.

Keep a close eye on the hours of daylight, as young marijuana plants need a minimum of 12 hours per day in order to get enough energy to grow. If you’re in the earlier part of the month where the daylight is still under 12 hours, supplement the natural light with a grow lamp. This is crucial because it prevents your plants from flowering early (which would be a huge waste).

If you are growing a mother plant for cloning, be sure it is ready by the start of next month, so there’s enough time for the clones to grow outdoors over the next few months.

October

Average day length: 12.5 to 13.5 hours
Average temperature: 11 to 22 degrees Celsius

The Desert:
Average day length: 12.5 to 13 hours
Average temperature: 15 to 32 degrees Celsius

start putting plants outside

If you are growing some of your plants on the windowsill, they won’t need any extra artificial light starting in October, as the amount of daylight is going up by quite a bit. Still, you are going to want your plants to receive the maximum amount of sunlight hours, so see if you can get at least 13 hours for your plants.

If the daily temperature is high enough (if you are living in the warmer parts of the country, for example), then you can remove your plants from the windowsill and place them outside instead. Once the daylight temperature rises to 21 degrees Celsius, this can be done. That said, be sure to bring your plants back in at night, since the temperatures will still drop lower then.

If it applies to you, begin making your clones from the mother plant during October.

November

Average day length: 13.5 to 14 hours
Average temperature: 13 to 25 degrees Celsius

The Desert:
Average day length: 13 to 14 hours
Average temperature: 18 to 35 degrees Celsius

put your cannabis plants outside

Temperatures should finally be high enough that it feels like real spring — or even summer! During November it is now okay to bring your marijuana plants outside all day and night, as long as the temperature doesn’t drop below 15 degrees

If you are growing autoflowering seeds, you can plant them during November so that you will be able to harvest towards the beginning of February.

Gorilla Glue Autoflowers

Gorilla Glue is one of the most popular strains on the market now. We offer an autoflowering variant of this delicious strain!

December

Average day length: 14 hours
Average temperature: 15 to 27 degrees Celsius

The Desert:
Average day length: 14 hours
Average temperature: 20 to 36 degrees Celsius

Plants are getting flowers

This is the last month that the number of daylight hours continues to increase. Starting in January, these hours are going to begin decreasing again. In other words, you can expect your marijuana plants to grow a huge amount during their vegetative phase this month. The growth should accelerate and accelerate. If you are growing autoflowering marijuana plants, flowers will start to show up.

January

Average day length: 14 hours
Average temperature: 17 to 28 degrees Celsius

The Desert:
Average day length: 13.5 hours
Average temperature: 23 to 39 degrees Celsius

Male vs female cannabis buds
Male vs female cannabis buds

January and February are the hottest months of the year, despite the fact that the hours of daylight decrease a bit. In January you can expect an autoflowering strain of marijuana to begin really flowering, producing large groups of flowers. Meanwhile, your “regular” (non-autoflowering) marijuana plants will start to form “pre-flowers.”

January is an extremely important month for growers of marijuana from non-feminized (regular) seeds. If you bought regular seeds, you could expect about half of your plants to be male. However, if they are not removed, the male plants will pollinate the females, greatly reducing your harvest.

You can identify the sex of a plant by looking at the “pre-flowers” a couple of weeks before they are capable of reproducing, so it is important to use this time to identify any male plants and remove them.

You can identify males and females by looking at what grows between their nodes. To identify the males, keep an eye out for small pollen sacs, which resemble little grape-like balls. The females can be identified from their bracts, which are teardrop shaped and will eventually grow wispy white stigmas from their pistils.

If you’re not sure of the sex of the plant, it’s a good idea to wait and see if a wispy white hair appears, telling you it is a female. But, watch the plants closely, and remove males as soon as you identify them.

February

Average day length: 13 hours
Average temperature: 17 to 28 degrees Celsius

The Desert:
Average day length: 13 hours
Average temperature: 22 to 37 degrees Celsius

dry your autoflowers now

Once your plant reaches the flowering stage, it can thrive at a comfortable room temperature with low humidity. Unless you are adding additional CO2 to your grow room, a temperature under 28°C is ideal. These lower temperatures encourage potent, trichome rich buds that you can smell and enjoy before you burn them.

Don’t go over 28°C, as higher temperatures cause terpenes to evaporate and they also slow bud growth. If your buds are too hot during this time, you may be literally burning away the good stuff as they grow, leaving very little taste or smell by the time of harvest.

Be especially careful to keep it comfortable for your plant after week 6 or 7. This is when terpene production is at its max, and you risk evaporating them due to high heat.

March

Average day length: 12 to 12.5 hours
Average temperature: 16 to 27 degrees Celsius

The Desert:
Average day length: 12 to 12.5 hours
Average temperature: 18 to 33 degrees Celsius

take marijuana plants inside

Autumn is on its way, but the temperatures should still be relatively high. Nonetheless, the number of daylight hours are dropping so the grow season is fast reaching its conclusion. If your plants are still hanging on and you haven’t harvested them already, it is probably a good idea to do that now.

Our free little Harvest Guide will help you determine the best moment to cut your plants. Download it here.

April

Average day length: 11 to 11.5 hours
Average temperature: 13 to 23 degrees Celsius

The Desert:
Average day length: 11 to 12 hours
Average temperature: 13 to 28 degrees Celsius

Bud rot on a plant
Bud rot

It is official: fall has arrived. April marks the definite end of the grow season. If somehow your plants are still going, harvest them now because the temperature could drop randomly and suddenly. If the weather gets cold or wet, then bud rot is a real risk (which would ruin your harvest). If you do discover bud rot, remove the entire bud immediately or else it will spread to the other buds.

While the entire Australian coast clearly does not have the exact same climate, the most important thing is to be aware of what your particular region and weather patterns are like. Keep in mind that sunshine is key: if your plants are getting enough sunlight, they should do just fine.

Enjoy your crop and be sure to check our indoor selection if you’re planning a winter grow.

Australia’s Top End, which encompasses the northern half of the Northern Territory and the areas surrounding it in the northern part of the country has a particularly unique climate compared with the semi-arid Red Centre (central Australia). While the Red Centre (and most of the rest of Australia) has four distinct seasons, the Top End has just two: the wet season and the dry season. Averages in this article are based on values from Katherine and Darwin, two cities in the Northern Territory, Australia.

Although warmth is never a problem in the tropical Top End, sunlight is surprisingly hard to come by. The daylight hours are quite a bit shorter in the Top End compared to the more arid southern regions of Australia, so it’s important to stay on top of how many hours of light are available for your plants. Some growers opt for autoflowering strains and grow two sets of marijuana plants since they are not photosensitive and the tropical grow season can last longer due to the warmer temperatures.

Since the grow season corresponds with the wet season (the time when most of the country is in its summer months), marijuana plants are at the highest risk for mildew and mold in the Top End. The main reason growers need to think about this fact is the fact that they can order seeds from plants that are more resistant to powdery mildew and other such problems, to begin with. This will help combat the potential for it.

Powdery Mildew

Powdery mildew (sometimes referred to as “white powdery mildew”) can decimate crops and entire marijuana gardens. It looks like white or gray powder is growing on the leaves of your marijuana plants. This type of fungi can spread easily and quickly, consuming everything in its path. Climates that include a high humidity (such as the tropical region of the Top End) tend to encourage the growth of powdery mildew. Anything above 55% humidity is comfortable for powdery mildew to develop – and the Top End consistently has the humidity in the 70% and 80% range. If your buds are infected with powdery mildew, the entire bud is ruined – so stay vigilant!

August

Average day length: 11.5 to 12 hours
Average temperature: 17.5 to 32 degrees Celsius

Start sprouting your seeds

At this point, you should be preparing (at least mentally, if nothing else) for the grow season ahead. While frost is never a risk here in the tropics, you can still wait until September to plant your plants since they will be cozy and warm.

Prepare for the grow season by ordering your seeds (preferably ones that have a strong resistance to mildew and mold) and preparing your growing area. Because seedlings grow best in temperatures between 20 and 25 degrees, next month will be perfect for planting with its warmer temperatures.

Visit my store if you’re in need of seeds. We ship to Oz daily.

September

Average day length: 12 hours
Average temperature: 21 to 32 degrees Celsius

sprouting seeds in the window

Buy your seeds now if you haven’t already. Start sprouting your plants once the number of daylight hours exceeds 12 per day. If that is not practical for you, you can begin sprouting the seedlings in the windowsill and supplement them with artificial light. If your plants aren’t receiving enough sunlight, they could flower early – unless they are autoflowering marijuana plants, of course.

Begin seriously growing any mother plants you might want to use for clones, as you will want to clip them next month already.

Once your plant reaches the flowering stage, it can thrive at a comfortable room temperature with low humidity. Unless you are adding additional CO2 to your grow room, a temperature under 28°C is ideal. These lower temperatures encourage potent, trichome rich buds that you can smell and enjoy before you burn them.

Don’t go over 28°C, as higher temperatures cause terpenes to evaporate and they also slow bud growth. If your buds are too hot during this time, you may be literally burning away the good stuff as they grow, leaving very little taste or smell by the time of harvest.

Be especially careful to keep it comfortable for your plant after week 6 or 7. This is when terpene production is at its max, and you risk evaporating them due to high heat.

October

Average day length: 12 to 12.5 hours
Average temperature: 25 to 35 degrees Celsius

sprouting cannabis outside sun

Now that the average daylight has exceeded 12 hours per day, you can move your marijuana plants outdoors safely. Since the temperatures tend to start getting pretty hot in October, you had better make sure your plants have enough water. The rain will start up starting in November and especially December, making this aspect easier for the grower. Start cutting your clones from the mother plant this month (if you are cloning).

Free Grow Guide

This is the time to brush up on your growing skills. My free Grow Bible can help you maximize the yield of your precious plants. Download it now

November

Average day length: 12.5 to 13 hours
Average temperature: 25 to 35 degrees Celsius

growing outdoor

Your plants should be growing nicely by now. If you are growing one set of autoflowering plants, you should plant them during this month so that you can harvest at the start of February. Of course, everything varies according to the specific strain, so be sure to do your homework before making any rash decisions.

This is the hottest month of the year, so keep making sure your plants are getting enough water. If it is a particularly wet November, the rain could help – but remember, it could also lead to the development of mold.

December

Average day length: 13 hours
Average temperature: 25 to 34 degrees Celsius

grow calendar first pistils

Your plants should be growing extremely well by now. They should be in the maximum growing time for the vegetative phase, meaning they should be shooting upwards and outwards. If you have planted autoflowering marijuana plants, you can expect them to begin flowering sometime this month.

January

Average day length: 13 hours
Average temperature: 24 to 32 degrees Celsius

drying cannabis strains

While January is on the warmer side of the Top End Australian climate, it is also the wettest month of the year. For that reason, mold and mildew are at their greatest risk. Stay vigilant.

This is a busy month for growers since “pre-flowers” will begin to grow and you should check to see which plants are male (assuming you purchased regular seeds rather than feminized ones). About half of your plants should be male, but should be removed or they will pollinate the females, greatly reducing your harvest.

You can identify the sex of your plant by looking at the “pre-flowers a couple of weeks before they are capable of reproducing, so it is important to use this time to identify any male plans and remove them. You can identify males and females by looking at what grows between their nodes. To identify the males, keep an eye out for small pollen sacs, which resemble little grape-like balls. Females can be identified from their bracts, which are teardrop shaped and will eventually grow wispy white stigmas from their pistils.

February

Average day length: 12.5 to 13 hours
Average temperature: 24 to 32 degrees Celsius

plant ready to harvest

It has probably reached the harvesting point for your autoflowering plants if that is what you planted. Clip the buds and hang them to dry. They should dry slowly but steadily over the course of about ten days. They are dry once a branch cracks when you bend it. Make sure to download my Grow Bible for more on proper harvesting.

The daylight hours have started to decrease again, meaning the harvesting time for your regular marijuana plants is on its way too. February still has plenty of rain, but things should start to die down again in March or April.

Blueberry Autoflower

If you’re quick you can grow two rounds of autoflowers this season. One of the biggest advantages of these fast flowering plants! Grab some autos here

March

Average day length: 11 to 12.5 hours
Average temperature: 23 to 33 degrees Celsius

The weather remains warm (as usual), but it is a good time to harvest your marijuana plants during this month simply because the daylight hours are getting down to the 12-hour mark. Some tropical growers opt to keep growing their plants for as long as possible, but it is up to you.

April

Average day length: 11.5 to 12 hours
Average temperature: 22 to 33 degrees Celsius

bud rot weed

The dry season is finally on its way, and you should harvest soon. Bud rot is still a risk because humidity remains high (and so does temperature, for the most part). If you do discover bud rot on any of your plants’ buds, remove those buds immediately and discard them because it could easily spread to the entire harvest. Hang your plant product up to dry after harvesting, and it should slowly dry over the course of 10 days. Make sure the drying room isn’t too humid, as bud rot could still easily develop.

Enjoy your summer harvest! And be sure to read up on indoor growing and grab some seeds so you can continue this awesome hobby!

Robert

The founder of I Love Growing Marijuana, Robert Bergman, is a marijuana growing expert that enjoys sharing his knowledge with the world. He combines years of experience, ranging from small-scale grows to massive operations, with a passion for growing. His articles include tutorials on growing... [read more]

23 Comments

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  1. By Lindsay

    ,05 Jan 2018
    Hi, can you do a grow calendar for New Zealand than you.
  2. By Roy

    ,06 Jan 2018
    Thank you for all the detailed information.There should be no excuse for an unsuccessful grow.Thanks especially for the Aus calender.
  3. By steve

    ,19 Feb 2018
    ok so in southern australia a photoperiod or regular female outdoor plant wont have mature buds until at least the 3rd week of april but more like early may . because the equinox or 12/12 light cycle dont happen until […]Read More
    1. By steve

      ,19 Feb 2018
      ok so in southern australia a photoperiod or regular female outdoor plant wont have mature buds until at least the 1st week of april . because the equinox or 12/12 light cycle dont happen until around the 3rd week of […]Read More
  4. By steve

    ,19 Feb 2018
    sorry screwed up the first post they will probably not go into may
  5. By latewood_ILGM

    ,20 Feb 2018
    steve, Thanks for your clarification. Keep in mind; The plant can start flowering before the 12/12 equinox.
  6. By steve

    ,20 Feb 2018
    yes but there's no thc in them and the idea that you need to pull while there is still 13 hours of daylight is just plain wrong Its 20 Feb now and my plants are covered in pre buds that […]Read More
  7. By Steve

    ,20 Feb 2018
    fathers day to mothers day Sep to May is traditionally the growing season here although sometimes you can be done by mid April. I don't think any oz outdoor growers would argue with that.
    1. By Ben

      ,12 Mar 2018
      steve is right you'll never harvest in south eastern Oz before the end of march ...its march 12th now and my thc bombs are still 2- 3 weeks away from being ready pure sativas can go to the end of […]Read More
    2. By latewood_ILGM

      ,18 Apr 2018
      Steve, #1...When you say Oz to me I think of ounce, and/or the prison in one of those cable networks. 2ndly; I do not understand what you are talking about. In one sense it sounds like all is good but, […]Read More
  8. By latewood_ILGM

    ,18 Apr 2018
    support.ilovegrowingmarijuana.com
  9. By Nina

    ,30 Jun 2018
    Hey, so is there is any suggestions on the "perfect" climate place in Australia? Thank you!
    1. By jollyjoker

      ,30 Jun 2018
      Adelaide as it has winters with out frost for outside plants (not the hills as they frost)
  10. By Danette

    ,06 Jul 2018
    What effect does the moon(light) have on outdoor growing? Do the phases have to be factored into the light/dark cycle?
    1. By Bignuts

      ,23 Oct 2018
      Hey Nettie , we like to germinate via moon cycles , first full moon in September which is start of spring . it’s really just a hippie thing don’t think it actually makes a difference , we also try harvest […]Read More
  11. By Joey

    ,17 Aug 2018
    Hello everybody 😎.just like to know if I planted a indica outdoor in Sydney in the start of September would it finish around Christmas time? Being and indica with a short lifespan? Anything at all would be a great help.thanks
  12. By Joey

    ,17 Aug 2018
    Hello everybody 😎 Being and indica can I plant in September and finish by Christmas. Sydney weather all outdoor...thanks
    1. By latewood_ILGM

      ,21 Aug 2018
      Joey, Outdoors plants get bigger and tend to take longer to finish. I noticed the days are over 13 hours in December, so I have reservations about your deadline. it might take you until January to finish outdoors. Hope this […]Read More
  13. By Bignuts

    ,23 Oct 2018
    Growing for over 20 years in OZ and never have I harvested any earlier than back end of April / Early May .. There’s a saying out in Byron Bay , Australia’s weed capital .... Plant Father’s Day harvest Mother’s […]Read More
    1. By That Flower Man

      ,29 Nov 2018
      It’s end of November, a couple have failed. Is it wise to plant more seeds? I have reservations as I don’t know how long veg period is... is it worth it?
  14. By Chris

    ,04 Mar 2019
    Hi, you may be well intentioned, but a lot of information here is dead wrong. E.g daylight hours decrease after late December in southern australia, but you have them increasing in january. Another: you refer to females producing pollen! I […]Read More
    1. By latewood ILGM

      ,07 Mar 2019
      Thanks Chris. you are right. sometimes the person translating the article from dutch to English makes a mistake. I iwill pass this up the chain to the office for editing. Peace

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