How To Grow Cannabis In Winter (Yes, It's Possible!)

Winter is here, and we’re getting a lot of questions from growers about cultivating weed during the coldest months of the year. And while it’s far from optimal, it is possible to push out a winter harvest. Keep reading to learn how.

CAN YOU GROW WEED IN WINTER?

Most cannabis varieties, especially sativas, typically like warm weather, plenty of sun, and some humidity. However, that doesn’t make it impossible to grow weed in colder climates or during the winter. Doing so is just a little more challenging.

HOW TO GROW WEED OUTDOORS IN WINTER

The easiest way to grow cannabis in winter is to move your plants indoors. Here, you’ll have to control variables like the light cycle, temperature, and humidity to create the ideal environment for your plants to flourish.

However, that’s probably not the answer you were looking for when you landed on this article—chances are you want to know whether you can grow cannabis outdoors in winter. And the answer is still yes, given you live in an area with mild winters. Here are five key considerations every wintertime grower must reckon with:

START WITH THE RIGHT GENETICS

If you want to grow cannabis outdoors in winter, forget about photoperiod strains and opt for autoflowers if at all possible. Photoperiod varieties require a change in light cycle in order to flower, and you won’t get that when growing outdoors in winter. In fact, if your plants are flowering toward the end of winter, they’ll likely start re-vegging once the days get longer—not good.

Autoflowers, on the other hand, will flower naturally based on age, regardless of how much light they get. Plus, all autoflowering varieties contain ruderalis genetics, which are naturally better suited to colder climates.

START YOUR PLANTS INDOORS

We recommend this to any outdoor grower, regardless of season. Cannabis seedlings are fragile and won’t last long outdoors in winter. If you’re planning for a winter harvest, start your seedlings indoors in a warm, humid environment. Also, consider investing in a seed starter kit to support your seeds as much as possible from day one.

Once your plants have started vegging (usually 2–3weeks after sprouting through the soil), keep them indoors until they’ve grown at least a few nodes and a sturdy stem. It can also be a good idea to introduce your plants to the outdoors gradually for the first week or so, taking them back inside when the weather gets rough.

KEEP AN EYE ON TEMPERATURE

Cannabis is a pretty hardy plant, but the cold is capable of killing your plants and ruining your winter harvest. Soil temperatures below 16°C will adversely affect the health of your roots and stunt their growth, affecting the health of the entire plant in turn. Above the soil, cannabis can put up with colder temperatures, but frost will kill off even the healthiest vegetation.

When growing weed outdoors in winter, make sure to pay close attention to the temperatures in your area. If possible, grow in smaller pots of about 10–12l that are easy to manoeuver, and consider moving your plants indoors when temperatures drop below 16°C.

WATCH OUT FOR RAIN

Another big threat to cannabis is humidity and rain. If you have experience growing weed, you’ll know that overwatering is a surefire way to kill your roots and attract pests, diseases, and mould.

Once your plants are mature, they’ll be much more hardy. But during the seedling phase, and the first few weeks of veg, cannabis plants are quite fragile. If your location gets a lot of rain in winter, consider moving your plants indoors during consecutive rainy days, or keeping them under some kind of cover like a tarpaulin.

CONSIDER A GREENHOUSE

Greenhouses are really popular in Europe, especially in areas where outdoor growers have to battle lower temperatures and high rainfall during winter. And while building a greenhouse obviously takes some initial investment, it’s one of the best ways to grow cannabis in winter because it gives you a lot more control over the temperature and humidity. Greenhouses also help your plants stay protected from strong winds, rain, and frost.

THE BEST COLD-RESISTANT CANNABIS STRAINS TO GROW THIS WINTER

Selecting the right genetics is always important when growing cannabis. But when you’re planning an outdoor grow, finding the right strain can truly make or break your harvest.

Below is a selection of some of the hardiest, cold-resistant strains to grow this winter:

• Sticky Beast Automatic (Zamnesia Seeds)

Sticky Beast Automatic is one of our best-selling autoflowers, bred by the experts right here at Zamnesia. A three-way cross between Bubble Gum, OG Kush, and Critical Auto, this is a profit-yielding auto that’s easy to grow, resilient, and produces some top-shelf buds. Developed in the Netherlands, Sticky Beast Automatic is a hardy plant that can battle the cold, and moves from seed to harvest in just 8 weeks.

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Sticky Beast Automatic (Zamnesia Seeds) feminized

(529)

Parents: Bubble Gum x OG Kush x Critical Automatic

Genetics: Indica-dominant Auto

Flowering Time: 10-11 weeks from seed to harvest

Potency: 16%

CBD: 3%

Flowering Type: Autoflowering

• Quick One Automatic (Royal Queen Seeds)

Created by the award-winning breeders at Royal Queen Seeds, Quick One is a fast-flowering indica-dominant auto. It’s ready for harvest within just 8–9 weeks post-germination and produces modest harvests of up to 45g/plant outdoors and 275–325g/m² indoors, although you can expect lighter harvests in winter. Anyone seeking a lightning-fast auto to pump out a solid stash of bud this winter would be wise to consider this cultivar.

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Quick One Automatic (Royal Queen Seeds) feminized

(140)

Parents: Strong Indica x Ruderalis

Genetics: Ruderalis/Indica/Sativa

Flowering Time: 8-9 weeks from seed to harvest

Potency: 13%

CBD: Medium

Flowering Type: Autoflowering

• GG#4 Auto (FastBuds)

Gorilla Glue is a US strain that’s now become a household name in many places around the world. GG#4 Auto by FastBuds crosses the classic with ruderalis to create a potent, resilient auto that’ll impress even the fussiest grower. If you want to grow some top-shelf US genetics this winter, there’s no better option out there than GG#4 Auto.

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GG#4 Auto (FastBuds) feminized

(390)

Genetics: 35% Indica / 65% Sativa

Flowering Time: 9-10 weeks from seed to harvest

Potency: 24%

CBD: 0-1%

Flowering Type: Autoflowering

• Taison Auto (VIP Seeds)

This unique auto combines Purple Kush with autoflowering genetics from Russia. The result is a really beautiful plant that develops dark purple, almost black buds. The smell and taste of this strain are very reminiscent of Purple Kush, and it delivers a knockout, Kush-style stone. Thanks to its genetics, Taison Auto is really hardy and well-suited to cold climates, making it an ideal winter grow.

TIPS FOR GROWING CANNABIS IN COLD WEATHER

Like we said earlier, while cannabis normally prefers warm and humid climates, it's not impossible to grow weed in winter, it just takes a little extra work. To help you through your next winter grow, here are some other simple tips for growing cannabis in cold climates:

• Grow autoflowers and indica-dominant strains

Indica varieties tend to originate from colder climates with shorter summers and harsher winters, hence they are genetically better suited to winter climates. Autoflowering indicas make things even easier as they are cold-resistant, fast, and don't rely on a specific light cycle.

• Plant early

Try to plant as soon as possible to avoid the harshest months of winter snow and rain.

• Have clear expectations

This is really important; remember that the weed you grow outdoors in winter will be different from what you’d normally grow. Don’t expect big, dense buds or heavy harvests when growing in subpar conditions.

• Consider moving indoors

The best way to grow great bud in winter is to move your grow indoors, or at least into a greenhouse if possible. While it’s more hands-on and involves investing in more gear, the increase in harvest quality and size are well worth it.

Steven Voser

Steven Voser is an independent cannabis journalist with over 6 years of experience writing about all things weed; how to grow it, how best to enjoy it, and the booming industry and murky legal landscape surrounding it.

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