can weed grow in cold weather

Growing Marijuana In Cold Weather

Published : Dec 19, 2018
Categories : Cannabis cultivation

Some think that growing weed with good yields in Northern climates is only possible during the short months of summer. But this isn’t true. You can also grow cannabis in cold weather if you know how to go about it. Read on to learn how you can grow marijuana in cold weather!


Most of us are not so lucky as to live in a warm climate like Southern Europe or California. Growers in those locations can cultivate their ganja all year round without much trouble, but the short summers and long winters in our climate (Northern Europe) aren’t exactly ideal if we want to grow cannabis. Then again, growing cannabis in cold weather is possible if you know how to go about it. Even better, the chillier temperatures in our climate can actually have some advantages for growing weed.

Those places around the world where cannabis grows out in the wild have plenty of sunshine, fertile soil, and an optimal outdoor temperature of 20–28°C. In Northern Europe, including the UK, the Netherlands, Germany, and many other parts of Europe, we can feel lucky if we get such optimal outdoor growing conditions for a few short weeks in summer. Then again, this doesn’t have to be a problem if we grow indoors.


The colder weather in fall and winter isn’t just a concern if you grow cannabis outdoors. Low temperatures can also affect your grow indoors. Your plants may avoid the threat of frost if they are away from the elements inside your home, but the lower temperatures combined with high humidity can still cause problems. For example, this can greatly increase the risk for mould and bud rot. However, whether your plants can get over the colder months will depend on several key factors. One of them is what type of grow lights you use.


If you’re growing cannabis indoors, as many do, the cold temperatures in fall and winter can actually be an advantage. This is true for growers who still use HID grow lights with MH or HPS bulbs. Although LED grow lights are becoming increasingly popular, the “old-fashioned” HID lights are still widely used among many. They are also the most affordable type of grow light, and cannabis growers have used these lights to successfully grow cannabis for a long time.

The problem with HID lights, however, is that these light fixtures create a ton of heat. This means that indoor growers often require special cooling systems in their grow room to keep the plants at a comfortable level. Not so during the colder months of the year! The colder temperature outside and the hot HID lights can make it so your plants can grow in just the right temperatures. This means no extra heating or cooling required for your grow room, which can help save a lot of money. Some growers take the colder months of the year as an opportunity to add more HID lights to their grow room for higher yields.


Modern LEDs are now almost, if not equally as powerful as HID lamps, yet they use only a fraction of the power of HID lights. This can add up to significant savings on the grower’s energy bill over time.

One difference to HID is that LED lights create significantly less heat. In general, this is seen as an advantage. During the warmer months of the year, LEDs won’t heat up your tent as much as HID, so you won’t need additional cooling for your grow room. Likewise, LEDs allow you to output lots of light and therefore maximise your harvest without risking heat stress or burning your plants.

On the other hand, LED lights can be a clear disadvantage in winter. Since they produce almost no heat, they can’t warm up your growing area as HID lamps do. This means you’ll likely require an extra heater so that your plants can thrive when it’s colder.

The same is true for CFL (fluorescent) grow lights that are still widely used for vegging. Just like LEDs, these lamps hardly create any heat, so you will possibly need some heating solution to keep your plants happy and healthy.


Contrary to what some might say, it is possible to grow weed with good results outdoors in cooler climates. You can in fact grow outdoor marijuana all year round if you plan your grow well. For example, it can help to know the weather particular to your area so you can time your harvest to beat mould and frost. Here are our tips on how you can grow marijuana in cold weather.


How well a cannabis strain does in certain conditions is highly dependent on its genetics. In other words, some strains are just better suited to growing in less optimal conditions than others. One problem in our climate zone isn’t so much the colder temperatures per se, but the rainy weather in fall. If a cannabis strain requires a particularly long flowering period that would extend into the rainy months, this can lead to mould, which could destroy your precious harvest in a short time.

As such, you want to select resistant outdoor cannabis strains that have a chance of surviving in these conditions. Fast-flowering strains as well as autoflowering varieties are particularly well-suited for growing in our climate zone due to their speedy lifecycle. Unlike strains that may flower well into late fall, these fast-flowering strains will be ready much earlier. If you are growing photoperiod strains, make sure that you choose varieties with a flowering period of 9 weeks or less.


Seedlings and young cannabis plants can be particularly sensitive to colder temperatures. Instead of planting your seeds outside, start your cannabis indoors and wait until they are strong enough for transplanting. Put them outside in late spring when there is no more risk of frost.


Building upon what we said earlier, autoflowers can be perfect for less than optimal conditions outdoors. Most autoflowers will only spend 30 days or less in the vegetative phase, and will then start to go into flowering on their own. Their entire lifecycle from seed to harvest can be as short as 8 weeks. This way, you can plan your grow perfectly so that you can harvest right before frost or rainfall. What’s more, autoflowers don’t rely on hours of light exposure like photoperiod strains do. This means you can set them outside to grow and flower independently of the season.


Better safe than sorry! If you’re growing outdoors, you never know what might happen. Even with the best planning, something unforeseen such as frost, unexpected storms, or animals taking a liking to your plants can always occur. If you keep a mother plant or two indoors in veg, you can ride out bad weather and other unexpected things. Should something happen to your crop, not all is lost because you always have a backup!


Let’s say you found a nice spot somewhere in a forest or in some other lovely outdoor location. If you can, don’t plant your outdoor crops directly in soil, but use pots instead. This way, you can easily move your plants should it turn out that the “sunny spot” you found in spring doesn’t look so great later on in the year. With your plants in pots, you will also have the option of bringing them safely indoors when frost or heavy rain is predicted.


To ensure your plants can survive any threat of frost, make sure to place them in a spot that gets direct sunlight in the morning. The reason for this is that it is better when plants can slowly defrost after a night of chill. This way, your plants may even be able to survive nights that drop below their healthy threshold for development. Growing spots near a lake or river can also be very good. They are naturally a few degrees warmer, so there is less risk for frost at night.

Tip: If frost is expected, water your plants in the evening. This protects the roots from freezing.


If you love to grow cannabis, you are not limited to the few warmer months of the year. No matter if you grow indoors or outdoors, with the tips from our guide, you can make sure that the colder temperatures won’t spoil the fun.

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You can grow marijuana in cold weather with great results. Here are tips for healthy plants and plentiful harvests during the colder times of the year!

Hot Tips For Growing Marijuana In Cold Weather

Growing marijuana in cold weather doesn’t have to be a misery. Allow us to demystify and share with you the secrets of cropping cannabis in the cold. Ganja farming in cooler conditions actually has one or two huge advantages.


We all know cannabis is an adaptable and incredibly versatile plant, that’s why it’s cropped all over the world. The optimal conditions for cannabis to thrive in the wild is planted in fertile soil with good sunlight, a mild breeze, and with consistent temperatures of 20-28°C.

Unless you happen to live in Australia, California, Colombia, Jamaica or someplace safe around the Mediterranean, the growing season is short and the weather is less than predictable.

Indoor cannabis cultivation is booming globally and in freezing northern latitudes it really is the only viable option. That being said, tremendous outdoor cannabis crops are also harvested in the cooler climates of Canada and Eastern Europe annually.

Amazing marijuana really can be cropped all year round, the trick is to tailor a grow plan that factors in the likelihood of inclement weather, that is particular to your area and if cropping outdoors thorough knowledge of the local climate, environment and sun cycles is crucial.

A little luck doesn’t hurt any either.


Every cannabis grow is dictated by the genetics the grower chooses to crop, whether you choose to cultivate with a batch of clones or start from scratch with seeds, the genes determine the crop’s ultimate potential.

Choose your cannabis strain especially carefully if you intend to grow outdoors in cooler regions. Indoor growers, that have their grow show perfectly dialled in from nutrients to environmental controls, can theoretically grow any strain any time of the year.

But that’s in theory, the reality is heavy snowfall and subzero temps, that can strike in the death of winter, will upset even an indoor grandmaster tuned grow show.

Should temperatures fall below 15°C, cannabis plants are effectively in the danger zone. The risk posed by pathogens and pests increases exponentially. Growth will cease and then leaves will discolour if the cold does not abate.

Outdoors only the hardiest most resistant cannabis strains have a chance of surviving a cold winter. And it’s a slim chance really not worth taking, if sleet and/or snow are likely. It’s better to be a flexible ganja farmer, than stubborn with no stash.

Even hardcore outdoor weed warriors will keep a mother plant or two indoors in vegetative growth to ride out the roughest weather. At the very least covering with plastic sheeting or housing inside a greenhouse is recommended.

Autoflowering strains are hands down the best varieties for the cold weather marijuana cultivator. Outdoor growers need to crop fast if conditions are less than perfect and to avoid the worst winter weather. Autos can be cropped from seed to stash in as little as 8 weeks from germination.

Ruderalis genetics make autoflowering strains extra tough and fast flowering. In fact, they will usually enter the bloom cycle in 30 days or less as they are not photoperiod dependent. This ability facilitates both out of season cropping and those restricted by a short summer.

Mold is the greatest threat to flowering cannabis in cold weather. High RH and low temperatures make a perfect breeding ground for fungus. Stay ahead of the worst weather and stick with fast flowering hybrids and autoflowering strains, that can be harvested before rains ruin the buds.

Use pots, that can be picked up and moved easily rather than getting stuck in the mud by sowing in the miserable patch that was sunny for two weeks in spring.


Old school HID systems emit a great deal of heat, as well as light. Keeping cannabis plants in vegetative growth with an MH bulb under an 18+ hour light cycle is actually easier in cold weather and a simple method to preserve mother plants and/or cuttings during the winter months.

Flowering with HPS lighting and vegging with MH bulbs usually requires serious air cooling. The old school grower can turn cold weather to his/her advantage and save some cash on the air conditioning bill at the same time. Some even add extra lights to boost yields when the weather gets cooler.


LED lighting systems are rapidly overtaking HID bulbs as the cultivation lamps of choice for Millennial weed growers, but the technology is still to be perfected. LED lights run cooler, because they emit almost 75% of their energy as light. This is fantastic most of the time and usually makes for easy environmental control in the grow tent.

However, LEDs can run too cold during the winter months. The simple solution is to turn up the heat. Unfortunately, this might negate the electric bill savings made by running the low wattage drawing LEDs.

High RH may also be an issue with LED systems in cold weather, a dehumidifier may also need to be added to the grow show and definitely during the bloom phase.

CFLs are more or less redundant during prolonged periods of cold weather, even the highest wattage bulbs available, with 300W, cannot generate sufficient heat to curb a frosty winter.

Bud rot is a real threat for growers cropping in cold weather with next generation lighting like LEDs and CFLs. Hydroponics and LEDs can be a recipe for disaster in cold weather, as both root rot and bud mold can be real threats if feed water is below room temp and RH exceeds 60% during flowering.

Maintaining environmental control year round is the only long-term solution; keep an eye on those thermometers and make adjustments when necessary. It’s a whole lot easier to heat a grow room in winter, than it is to cool a sweltering HID grow show in high summer.

Old school HID growers may be able to avoid turning on the heating during the dark cycle if they run their lights during the cold winter nights. Daytime temperatures are usually a little higher, so it might be possible.

LED aficionados face the prospect of running the heating virtually nonstop. Perhaps a combo of HID and LED is the smartest compromise in freezing conditions for the modern indoor cannabis grower.

We almost forgot to mention cropping cannabis in cold weather has the huge advantage of increasing the chances of certain strains displaying beautiful lilac and deep purple shades every weed grower covets most.


With the best grow system in place for your needs, you will hopefully achieve superior results. Since you are taking such care for your set-up, you may also want to choose the magic ingredient carefully. As curators of the finest seeds, Royal Queen Seeds knows the strength of seed you choose is crucial to the whole process. We also happen to know which strains are likely to thrive best in colder climates. We have put together a list of 5 strains that have the resilience, adaptability, and other qualities needed to deliver healthy yields in colder temperatures. All of these seeds are available to order from us now.


You will find few cannabis plants as resilient as our Critical strain. It will even grow well in cold climates of the north. The flowering time of around 7 weeks ensures speedy results. The sho rt height is also easily manageable in restricted growing conditions. An indoor Critical plant will only grow to 80–140cm. The buds have a sweet, earthy smell, and will amount to yields of about 550–600g/m².

This hybrid owes its sativa properties to Skunk and its dominant indica side to Afghan landraces. Afghan plants get their lineage from highly potent and resilient plants of the Hindu Kush mountains. Therefore, you are going to enjoy pure tingling sensations that relax both body and mind, thanks in part to a THC content of around 18%. You won’t know what your grow is missing until you give our Critical seeds a try.

Cold weather cannabis cultivation can be perilous but it's by no means impossible. We've got the red hot tips to help you crop dank weed in the dead of winter.