Grow Calendar Australia

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.

Aussie Grow Facts

• 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 growing marijuana in Australia!

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

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.

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

Buy Sunny Climate 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.

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

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

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

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.

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

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

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 feminized 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

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

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

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.

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.

Be sure to check our indoor selection if you’re planning a winter grow.

Buy Indoor Seeds

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

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.

September

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

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

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).

November

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

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

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

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 feminized 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

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.

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.

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

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!

Feeling confident to grow your own marijuana in Australia? Grab some seeds from my shop to get started!

Buy Marijuana Seeds

FAQ About Growing Marijuana in Australia

Practice and learning are what it takes to become a pro grower! Feel free to visit my blog for all the grow information you need.

What’s your favorite strain to grow in Australia? Share with us in the comments!

Happy growing!

Robert