Growing marijuana basing on latitude

Marijuana is a plant that grows outdoors throughout the entire world – except in the Poles – either wild or under the care of a farmer. For a crop to be successful, we must consider when to grow it and the most suitable marijuana strain to use. This post aims to provide information on growing marijuana based on the latitude in which we are.

Climate world map

Climate world map

The latitude on the Earth has a direct impact on photoperiod, in other words, on the daily hours of darkness and sunlight. In turn, latitude also determines the planet’s geographical zones. Taking into account that marijuana is an annual plant – it germinates, flowers and is harvested in the same year – and that its different phases are related to the photoperiod, we come to the logical conclusion that, based on our geographical zone in the planet, the growing period of cannabis varies. Mild temperatures and low humidity during the flowering stage provide the ideal conditions for harvesting top quality marijuana.

To simplify the information, as it’s a very broad subject, three major areas have been identified: northern hemisphere, intertropical zone and southern hemisphere.

Growing marijuana in the Northern Hemisphere

It comprises the half of the world that is north of the equator. The longest day in the year occurs between 20 and 23 June (summer solstice). The shortest day (winter solstice) is between 20 and 23 December. Day and night are the same length (equinox) on 20 March and 22 September. For cannabis farming, we will mainly focus on two areas: the Iberian Peninsula and the Canary Islands.

Marijuana in the Iberian Peninsula

It is situated between the 36º and 44º North. Although its climate is mild due to its latitude, crops must be adjusted to the climate and latitude of the area where they are grown.

Early Maroc from Philosopher Seeds, almost ready to harvest

Early Maroc from Philosopher Seeds, almost ready to harvest

Luckily, in the Iberian Peninsula almost all marijuana strains grow in perfect conditions. The only problems that a grower may encounter are with equatorial sativa strains that can finish their flowering by the end of November or even December.

The ideal months to start growing marijuana are March, April, May and June. You can also do it in July and August, but only the autoflowering strains are recommended in this case, for they do not depend on photoperiod but need a maximum of sunshine – and daily light hours – for a productive yield. In addition to the last chances of frost during spring, choosing the month we start growing depends basically on the strain and its needs, so if we have enough space, planting during the waning moon in March can produce large plants of the size of Moby Dick from Dinafem, Domina Haze from Kannabia or Jack Herer from Sensi Seeds.

If you are growing marijuana on a terrace or in pots, April and May are ideal months to start growing early strains. Early Maroc from Philosopher Seeds is an option to bear in mind, as it can be harvested in the first half of August. Plant it in June if you want to control the height or reduce the growing time of sativa strains. Notice that the cycle of cannabis plants ends in Autumn, so you should choose the fastest plants according to the Iberian Peninsula latitude, as they can be harvested before the cold and heavy rain period start.

Types of weed for the Canary Islands

The Canaries are located between 27º37′ and 29º25′ North. The climate is mainly subtropical, but it varies depending on altitude and slope, north and south. Except in areas with cooler microclimates, on these “lucky” islands you can grow at least two outdoor crops per year naturally. The planting months are from March to June and from September to November, to be harvested in March, always depending on the strain and its quality.

Growing marijuana in the intertropical zone

Tropics are the region between the Tropic of Cancer and the Tropic of Capricorn. In the intertropical zone there is little variation on the photoperiod throughout the year, while in the equator (latitude 5° N / 5° S) there is a constant photoperiod of 12 hours of daylight and 12 hours of darkness.

Neville's Haze from Mr Nice

Neville’s Haze from Mr Nice

As we approach the Tropics there is a maximum variation of one hour during the day, which varies in the calendar depending on whether you are located north or south. For example, in the Tropic of Cancer, the months with more daylight hours (13) fall between May and August, while in the Tropic of Capricorn, it will be between November and February. As for the weather, usually these are warm areas with no frost risk. However, like in the rest of the planet, this may vary depending on altitude.

Given the photoperiod in these latitudes, marijuana can be grown all year round and the plants behaviour will be almost like that of autoflowering strains, i.e. they will go into flowering when they reach maturity, regardless of the current photoperiod.

A hindrance when growing weed is rain, specially during flowering. It is recommended to be prepared for drought and rainfall periods so that we choose the right month to harvest. Direct rain water to plants should be avoided during the flowering period, so using a cover can solve the problem of rain. However, suffice it to say that cloudy skies have an impact on harvests and final yields.  

In the intertropical zone, Indica strains don’t grow as vigorous as in areas further from the equator. However, the tropics characteristics are ideal for Sativa strains, local or commercial strains containing tropical genetics such as Acapulco Gold from Barney’s Farm, Oldtimers Haze from Ace Seeds and Neville’s Haze from Mr Nice, for they will easily adapt to these conditions.

A good way to overcome nature constraints when harvesting marijuana is using a grow lamp in order to grow the plants indoors or in a greenhouse, and taking them outdoors when we wish to make them flower.

Growing marijuana in the southern hemisphere

The southern hemisphere is the area located south of the equator. The day with more daylight hours in the year is 21 December, which is when daylight hours begin to decrease. The shortest day falls on 21 June, coinciding with the winter solstice. On 21 March and 21September, day and night are of equal length. These are called fall and spring equinoxes.

What are the best marijuana strains to grow in Argentina, Uruguay, Chile, Paraguay, southern Brazil, South Africa… 23° to 33° south

In the area comprising 23 and 33 degrees south, the months with more daylight hours are November, December, January and February. Depending on the area, we find subtropical or semitropical climate in all its variations. In most of the area the climate is mild, but because of its montainous landscape there may be serious chances of frost and even snowfall.

White Afghan (23 to 33 degrees south). Depending on altitude, at this latitude, at least two outdoor crops can be produced without artificial light.

White Afghan (23 to 33 degrees south). Depending on altitude, at this latitude, at least two outdoor crops can be produced without artificial lighst.

In warmer areas it is possible to grow two outdoor crops per year. In the winter, the yield will be poorer, which is ideal for experimenting with local seeds. In the summer, selected cannabis seeds are recommended, so you can grow strains such as Nexus from Eva Seeds, Channel + from Medical Seeds and Easy Haze / K13-Haze from Philosopher Seeds . You can get excellent yields in terms of quality and quantity ensuring a great stash of marijuana for the rest of the year.

What are the best seeds for Argentina, Chile, South Africa… 33º to 50º south?

In these latitudes, the four seasons are perfectly differentiated, so there are chances of frost in almost all areas, being abundant in high areas and of course, in areas nearer the South pole.

The ideal time to start growing marijuana depends on altitude and risk of frost – either at planting or harvesting – of the area where it is going to grow. It is also recommended to take into account what strain is planted in a certain month -this will avoid unexpected results regarding the final size of the plant.

Mataró Blue from Kannabia Seeds, late October

Mataró Blue from Kannabia Seeds, late October

For those experienced growers seeking large plants, September and October are ideal months to start growing.  For beginners, a good option is to start growing autoflowering strains, for they are fast and thus avoid salt accumulation or potential pests that may occur in regular seeds during the 5-9 months of their cycle. It is recommended to pay attention to the weather, as frost is still a risk. By covering your plants or moving them indoors at night you can avoid wasting time and money.

If you start growing in November or December, you will avoid problems related to low temperatures. Marijuana plants are nicely developed with 14-15 hours of sun in this season and if the growing conditions are good you will get large plants, whether you are growing them potted or in-ground. These months are also ideal for growing autoflowering strains, such as Maxi Gom from Grassomatic, Deimos from Buddha Seeds and Jack 47 Auto from Sweets Seeds, as they are productive cannabis strains despite being automatic. If Rudelaris genetics are not available, any regular strain will develop well.

Mataró Blue from Kannabia Seeds, late December

Mataró Blue from Kannabia Seeds, late December

January is perfect if you want to grow sativa cannabis strains that do not exceed 250 cm in height. You can also grow indica strains, but they won’t get big, although they will be perfectly developed, especially if planted in the early days of this month. Growing autoflowering seeds is recommended – as well as during the mentioned months – even at the end of February, when you can also start growing tropical genetic seeds. In this case,keep in mind the weather conditions when harvesting it.

Mataró Blue from Kannabia Seeds, about to be harvested

Mataró Blue from Kannabia Seeds, about to be harvested



As in the mild area of the northern hemisphere, plants will end their cycle in Autumn. Based on the strain, climate and when you started growing it, the harvest can be between late March and May. Some pure sativa stains can be harvested in June.


October 6, 2014 | Outdoor cannabis growing

35 comments on “Growing marijuana basing on latitude

  1. Motlotlegi

    hi, i browsed through your article searching for information that will guide me through a plantation process whereby im interested in growing a marijuana plant that, its height wont protrude higher than 30cm and will produce kush that has a less tiring effect. my ideal location is tropic of capricorn, southern africa. can you please provide information? including of course how to get a hold of the seeds or how to produce them at my own peril.

    thanx 🙂

    1. Dani Alchimia

      Hello Motlotlegi,
      If you are looking for a strain short in size, you should look for pure Indica plants or autoflowering strains. The problem is that most indicas have a narcotic/sedative effect, which is not what you want. Thus, I think you should look for short, mostly sativa autoflowering strains , which won’t grow at all like normal strains and will produce an uplifting/stimulating effect.
      Unfortunately, we are not shipping our products to Africa, so we can’t help you getting these seeds.
      We hope to publish a post about the basics of breeding in a few weeks, so you can start thinking about making your own seeds.
      Thanks for your confidence,
      Best vibes!

  2. Prog-Delic

    Thank you

  3. Chillwill

    We’re is the best reliable seed bank and will thay ship anywhere in the U.S.

  4. Nizar

    Hello, im moving to the canaries soon, wanna still make the closest window on March, what do I need? I wanna grow different strains outdoors and maybe some indoors just to know how and try them

    I like Sativa strains, i prefer the happy/energetic mood,

    We r a few friends and we will plant enough ?

    Best regards,

    1. Dani Alchimia

      Hi Nizar,

      Basically, growing in the cannaries is almost like growing autoflowering strains. Unless it is midsummer, when they may grow for some extra weeks, plants are usually ready to harvest after 3-5 months from seedling (depending on strains, Sativas will take longer). Here you have a list of some of the best Sativa hybrids on the market. Since plants start flowering at almost any time of the year, many growers grow them a little bit indoors and put them outdoors when they have the desired size to begin flowering.

      The canaries are affected by sirocco coming from Africa, so perhaps you need to protect your plants from this hot and dry wind, otherwise they could wilt.

      Hope it helped!

  5. Scubasteve68

    If i started my plants in late june in e colo just east of mountains how big will my plants get outside will they bloom in sept?

    1. Dani Alchimia

      Hi Scubasteve68,

      Well, it depends on several factors:

      -Pot size (if you want big plants plant them directly in the ground)
      -Daylight hours (the more direct sunlight they have, the more they’ll grow)
      Nutrients (the more accurate the feeding, the more they’ll grow)
      -Genetics (mostly Sativa strains grow much taller and wider than Indicas).

      Depending on these factors, you plant can reach 1-2 metres in height, approximately.

      All the best!

  6. David

    How are you any suggestion on outdoor plants for Ireland I have a greenhouse will autos work thank you any help will do

    1. Dani Alchimia

      Hi David,

      Autos will do in Ireland, especially in a greenhouse, although you should grow them during the warmest months of the year. Photoperiod strains with early flowering could also work, like Early Maroc from Philosopher Seeds or C-99 from Female Seeds.

      Best of luck!

  7. Artemis2318

    Hi! What strains can you suggest that suit the climate in Central America, especially for a newbie grower?

    1. Dani Alchimia

      Hi Artemis2318,

      Doubtless, and because of the natural photoperiod of your area, I’d try Sativas or mainly Sativa hybrids. This type of plants grow much more vigorous and taller than Indicas, and are perfect for your climate conditions.

      Hope it helped!

  8. Breton

    We just passed recreational and legal grow for up to 12 plants in Massachusetts. Final frost is first week of April, we get almost no rain all summer and a peak temp right around 85 F on Cape Cod. We make it to 12/12 right around mid/late October. 42parallel. I would love some input on ideal strains for this area. Thanks!

  9. juan ochoa

    Hello, I would like suggestions on strains for tropical climate outdoors, exactly at 11 latitude, i am growing a seedling with 60% critical mass 40% white widow and its growing well despite the cloudy days we have had since its germination. i am also concerned about mold because of high humidity almost all year round… thank you

    1. Dani Alchimia

      Hi juan,

      Since you probably won’t have problems with cold temperatures, and taking into account that you grow in an area with high environmental humidity, I’d try hybrids with Sativa dominance. Sativas are more resistant to fungi than Indicas, which often develop more compact buds and are more sensitive to mold infections.

      All the best!

  10. freddy

    Thanks dani! One more question. My mother plant snap
    ped due to wind, I taped it up in hopes of re generation. Is that a good idea? Or should I cut my losses and take clones?

    1. Dani Alchimia

      Hi freddy,

      It’ll probably regenerate, cannabis is a very tough plant, although I’d take a couple of clones if possible, just in case!


  11. Isleno

    Hi, very helpful article, thank you very much!
    I am at 32° 38″, so close to canaries, what advice would you give me on grow schedule and my best bets? Weather is also rather close to canaries: no frost ever, no negative temps, maybe aniversário average humidity….
    would love some info for future planning anos possibilities.
    For the moment I have a small terrace that gets direct sun all day however size is a big concern unfortunately so I’m thinking of very small autos to be safe… 🙁 Less than 1 m high is the maximum at the moment, any specific advice on that for not a Pure indica? Would rather have a sativa dominant but doubt it would be possible?
    Thanks in advance!

    1. Dani Alchimia

      Hi Isleno,

      You have a nice weather to grow cannabis, although in your latitude plants don’t grow much and start flowering as soon as they reach sexual maturity (3-4 weeks). If you’re interested on mostly Sativa autos, I’d definitely try Philosopher Seeds Cheesy Auto, Sour Ryder ASB or Dinafem’s Amnesia XXL Auto.

      Hope it helped!

  12. Isleno

    Thanks for the fast and helpful response!
    So, if I understand correctly, it should be all year like “flowering” hours, is that it? I would BE able to use photoperiod and clones for quick harvest and not big size…Or vegetate indoors then take outside? This is good news to maybe not depend on autos.
    Light pollution is a concern however… But this info should push me to try a photoperiod to see how it turns out for a test.

    1. Dani Alchimia

      Hi Isleno,

      I’d definitely try some photoperiod strain and see how it performs. Most people I know who live in Canaries use their outside yard as a flowering room, they know plants will start flowering as soon as they’re taken outside during – almost – all year, so they grow them indoors and take them outside when they have the right size.

      Light pollution may be a problem, although I can perfectly read a newspaper at night in my yard next to my flowering plants, they’re less sentitive to it than we normaly think.

      Hope you’ll be lucky!

  13. Alexander

    I would like to grow Autos outdoors, im located in 31N 32E
    Can you recommend best indica/sativa auto strains for this climate

    Many thanks

    1. Dani Alchimia

      Hi Alexander,

      With your climate, as long as plants have enough irrigation they’ll be ok. Most of the automatic strains in our web will adapt perfectly to your climate and location.

      That being said, I’d recommend you Fraggle Skunk Auto if you want high yields, Sweet Nurse Auto if you want CBD and a more medicinal effect, or OG Kush Auto if you want a tru intense effect.

      Hope it helped!

  14. Mic

    What strains do you recommend for the intertropical zone around the Tropic of Capricorn. Would sativa dominant strains veg longer

    1. Tim Alchimia

      Hi Mic, thanks for your question. Wow, how lucky you are to grow in those latitudes, you’ll be able to grow some amazing tropical sativa genetics there for sure! Firstly I’d look at landrace varieties from countries that have a similar latitude, here at Alchimia we stock two highly reputable seed banks that work with landrace sativas, firstly ACE Seeds who have some excellent pure varieties from Panama, Honduras, Ethiopia, and Malawi as well as some very interesting sativa hybrids like Zamaldelica, Golden Tiger, Old Timers Haze or Tikal. Then we also have Cannabiogen with their Colombian Red or Destroyer (Mexico x Colombia x Thai). Other varieties worth mentioning are Zambia from Tropical Seeds, Double Zamal from USC, Mangu Karot from French Touch.

      Those are just a few suggestions, but by searching our shop for “landrace” or “sativa” you’ll see a whole range of options. Have fun deciding! All the best and happy growing.

  15. Joey

    Hello.just want to know if I plant in August in Sydney Australia when could I look at Finishing .I have MBs xwhite widow .c99 …it’s still a little cold start them in greenhouse and plant out .never grown out of season before.and would they stretch alot..thanks your knowledge would be greatly appreciated……

    1. Tim Alchimia

      Hi Joey, thanks for your question. At that time of year there are only 10-ish hours of daylight in the day, so the plants would begin flowering as soon as they’re mature, usually after growing 4-5 sets of leaves. They won’t grow very big with so few hours of light, and they oughtn’t to stretch too much either. If you want to give them a better start I’d recommend starting them indoors and growing them under lights for a few weeks, letting them get to a bigger size before putting them in the greenhouse to flower.

      All the best with your grow, happy planting!

  16. Daniel

    well, this make sense of why my plants started to flowering so soon(intertropical country), well, next time I will try in the “dry season”, next time I will try an hybrid indoor/outdoor, get some lights and run them for 3 to 4 hours when it get dark so they can grow a bit then turn them of to flower, also what strains you guys recommend for intertropical countries?

    also there is a chance you guys ship to Costa Rica?


  17. harlz

    hi what are the best strains to grow outdoors in new zealand ? cheers

    1. Tim Alchimia

      Hi harlz, thanks for your question. So I can help you, can you tell me roughly which part of NZ you’re growing in? There’s quite a difference in seasonal conditions between the top of the North Island and the bottom of the South Island, which would greatly affect your choice of variety.

  18. James P Yale

    Hello Tim: nice website ya got about some outdoor grow recommendations for southwest Florida?..

    1. Tim Alchimia

      Hi James, thanks for the kind words, and for the question too.

      Really the best thing is to talk to local growers and see what they’re planting and how they do it, but I also realise that in non-legal states this isn’t as easy as it sounds, so I’ll help the best I can. I don’t know too much about growing conditions in your area, but I do know that it’s generally fairly humid there and that mold is a very real risk. We have a post all about, but it’s really aimed at more northerly growers, whereas you’re quite far south so you have more options open to you.

      so for outdoor growing, you’ll probably be best with something very Sativa-leaning, almost pure. The looser, more airy floral structure will greatly help to keep botrytis/bud-rot to a minimum, and I don’t imagine you suffer from frosts in autumn, so your flowering season will be easily long enough for these varieties.

      Personally, I’d be looking at varieties based on landrace strains from the general area/latitude, so start with Central American and Caribbean varieties like,,,,, etc. and the various containing them can also offer another interesting option.

      I hope that’s helped you out, if you need any more advice, don’t hesitate to ask.
      All the best and happy growing!

  19. Tan

    Hey there, this is a very nice article and it is very helpful thank you!! I live in the tropics located 22.3° N, 73.18° E
    This year I am planning to grow during September but I am confused whether the plants will flower or will it continue its vegetative growth once it matures. Maximum sunlight received from September to February will be less than 12 hours, somewhere around 10 hours. But after the winter solstice that is 22 December will my plants still flower or continue vegging? So, my question is should I grow feminized seeds during this period or should I grow autoflower?

    1. Tim Alchimia

      Hi Tan, thanks for the question. If the daylight hours are less than 12 or 13, then the plants will continue to flower, no question. As long as the conditions are warm enough then you’ll be able to grow some amazing long-flowering Sativas. Autoflowering plants are not designed for your latitude, they’re for much further north where plants need to flower during the long days of summer to avoid the early autumn cold and rain. Where you live, plants can flower pretty much all year round, and you’ll be best planting Sativas which will give you the best vegetative growth before flowering. Indicas and Indica-dominant hybrids will stay very small and produce very little as the will begin flowering as soon as they are mature, behaving pretty much like autoflowers do. Sativas, however, can be germinated under 12/12 photoperiod and still easily reach 7ft tall by the time they finish! I hope that’s cleared things up, all the best and happy growing!

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