BackHow to choose the best cannabis seeds for cold climates

Growing cannabis outdoors can be a real challenge, especially in colder climates with short growing seasons. Choosing the right strain can significantly improve the chances of a successful harvest, even in regions where temperatures are low and weather conditions are harsh. There’s also a number of key factors that you must take into account when selecting the best cannabis varieties for this purpose.

 

Before we begin, let’s answer the big question: Can you grow cannabis in cold climates? The answer isn’t that simple and depends on several factors, such as the minimum temperatures in your region, the environment you’re in, the precautions you take, your growing skills, the choice of strain, and much more. Having said that, you can easily grow cannabis in cold regions if you play your cards right. It may not be the ideal environment for your plant, as cannabis loves warm climates that are blessed with abundant sunshine. And just as you perform best in an environment that is right for you, marijuana plants behave in exactly the same way. If cannabis is forced to live constantly in low temperatures, its development will gradually slow down. Once the thermometer drops below 15°C, its metabolism will gradually decrease; enzymatic and biochemical processes won’t be carried out; vegetative vigour may also fail; and its root system may not expand as it should, preventing it from absorbing as many nutrients as usual. The result is a weak plant that grows slowly and produces poor harvests. Additionally, cannabis plants don’t usually tolerate frost very well. Temperatures below 0°C can severely damage their structure, especially the youngest leaves and tissues, causing necrosis (cell death) and drastically reducing their ability to grow and flower. Therefore, to get the best results, especially in regions with freezing temperatures, it is advisable to grow cannabis indoors during the coldest months of the year. But in other warmer regions, you can easily manage using greenhouses, protective tunnels, or insulating mulch. You can even find growers growing autoflowering cannabis outdoors in Scandinavian areas, in even the coldest temperatures. Therefore, you must find out which method works best for you. And, to achieve this, you must start by choosing the best type of seed for your grow.

 

 

What type of strain should I choose for cold climates?

An obvious choice when selecting genetics that are resistant to adverse weather conditions are autoflowering strains, such as Auto Polar Gelato, Auto Tropicana Cookies, or Amnesia Auto. Thanks to their ruderalis lineage, which originates from regions like Siberia (where cannabis adapted to the adverse climate and different lengths of day and night), automatic plants are hardier and don’t depend on the photoperiod. In other words, they don’t have to wait for the days to become shorter to start flowering, so you can choose the 2 - 3 warmest months of the year for your grow: You can plant them in early summer and harvest them in early September, before it gets too cold and rainy, so you can harness the power of the sun in the months with the highest sunshine. The varieties known as ‘Fast’, ‘Early’, or ‘Fast Flowering’, with examples such as Early Top Skunk, Purple Punch Fast, or Critical Poison Fast, are also an innovative solution for growers looking to deal with low temperatures without sacrificing the quality of their crops. By crossing autoflowerings with photo-dependent plants, it was found that the new strains were still photo-dependent but with a faster flowering cycle of 6 - 7 weeks (i.e., 1 or 2 weeks faster than that of their conventional counterparts), which is a great advantage for cannabis growers in regions with short summers. You can also opt for feminised or regular strains, which are the ones that the majority of growers prefer because they produce a higher yield. Some of these varieties are highly resistant to cold and also have a fast flowering cycle, which can help reduce the risk of frost damage. If you don’t know the time of harvest outdoors, look to see how many weeks it takes for your plants to flower indoors: between 7 and 8 weeks is a good number, whereas 9 to 10, or more, means that the specific strain isn’t as suitable for harsh climates.

 

Other factors that influence the choice of seeds for cold climates

In addition to the type of seed and its flowering times, you also need to pay attention to other factors when looking for the best cannabis seeds for cold climates:

 

Genetics and adaptation

Always choose a genetic lineage that includes strains that evolved in harsher weather conditions, making them less susceptible to cold stress. For instance, Hindu Kush is native to the mountainous region between Pakistan and Afghanistan, an area known for its harsh climate. Some strains were also developed specifically for mountainous or northern regions, such as Nepal Gold or the Scandinavian genetics, which are better adapted to withstand low temperatures. Therefore, they are excellent for tolerating strong winds or severe thermal drops during the night.

 

 

Resistance to fungi and disease

Cold, when combined with frequent humidity, can increase the risk of diseases such as mould, botrytis (grey rot), or powdery mildew. It is crucial to choose varieties that have natural resistance to these diseases, such as Critical + 2.0 or Auto Fat Blueberry. It also helps to choose varieties with well-spaced, airy buds that can keep these annoying guests at bay in high humidity conditions.

 

Indica dominance

The compact and robust structure of indica strains is one of their main advantages for cold climates. These plants tend to grow shorter and with densely populated branches, which helps protect them from winds that could damage more slender varieties. And this dense foliage not only contributes to their leafy appearance, but also acts as a natural heat insulation layer.

 

Great resin production

The dense and resinous buds that some genetics produce not only contribute to their potency but also offer some protection against cold and humidity. Cannabis trichomes exist to protect the plant from environmental hazards such as cold, pests, or strong ultraviolet rays. Therefore, you can take advantage of the low temperatures to increase resin production using the plants’ reaction to stress. As a result, your harvest will be tastier, more potent, and of much higher quality.

 

Genetic stability

If you grow cannabis in an ideal environment, such as a controlled grow room, the strain’s phenotype will be fully expressed. But if you don’t have a stable variety, then it’s quite a different story. For example, genetics like Northern Lights, White Widow, or Afghan Skunk are known especially for their incredible yielding capacity even in cold temperatures. They derive from a robust genetic line that has been bred and refined over a long period, helping to ensure a consistent quality.

 

Purple strains

Another good reason to grow marijuana in cold climates is that you can get to witness the vibrant colours of the purple and blue varieties, such as Purple Kush or Gelato #33, which take on deeper tones when the cold is more intense. Exposure to low temperatures can induce oxidative stress in the plants, leading to an increase in the expression of genes associated with anthocyanin synthesis. This positive regulation results in a greater accumulation of these pigments, which work similarly to an antifreeze to safeguard cellular integrity, and which also cause an intensification in the colouring, with magnificent tones seen in the last weeks of flowering.

 

 

As you can see, growing cannabis in cold climates is not only possible, but can also be rewarding and even visually dazzling, provided you choose the right seeds and adopt the correct growing practices. Prioritise hardy and stable genetics that are adapted to cold temperatures and have a fast flowering cycle; and use a greenhouse, thermal covers, or mulching to optimise the growing conditions. With these strategies, you will maximise your chances of harvesting quality buds even in the most challenging situations. Good luck with your next grow and stay warm out there!