outdoor winter grow

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. ]]>