How Long Does It Take to Grow Weed?

New to the world of cannabis and wondering how long weed takes to grow? You’re not alone – many rookie growers wonder the same. Unfortunately, the answer to this all-too common question is far from straight-forward. Below we’ll walk you through a timeline of the average cannabis grow and teach you all there is to know about how fast (or slow) weed can grow.

Cannabis is, in general, a hardy and vigorous plant that grows very quickly – just like a weed. Indoors, for example, cannabis growers can expect to harvest their plants within just 2 months if they’re growing speedy genetics.

However, growing cannabis can also take much longer. Take on the challenge of cultivating a big sativa outdoors, for example, and you could be waiting for well over 6 months to taste the fruits of your labour.

On average, cannabis takes around 3-4 months to grow, but there are many variables to consider. Keep reading to find out what they are, as well as a detailed walkthrough of the different stages of a cannabis grow.

A breakdown of the cannabis life cycle

Cannabis plants go through 3 very characteristic stages of life:

1. Germination and seedling phase

This is when plants are at their most vulnerable and usually grow the slowest. Most growers consider their plants to have exited this stage and entered the vegetative phase once they’ve developed 1-2 sets of “true leaves” – that is, leaves with multiple leaflets or fingers (not cotyledons or seed leaves with a single leaflet).

2. Vegetation phase

During this stage, cannabis plants dedicate all their time and energy to developing healthy roots, leaves, branches, and “bud sites” – the areas from which cannabis flowers form.

3. Flowering phase

During this final stage of their lifecycle, cannabis plants develop reproductive flowers. Female plants will start flowering after their male counterparts, which tend to bloom a little earlier to ensure they are able to pollinate the females. Photoperiod cannabis strains will start flowering in response to changes in their light cycle, while autoflowering plants will flower automatically once they reach a certain age due to their ruderalis genetics. Learn more about the difference between Cannabis sativa, indica, and ruderalis here.

How long it takes for a cannabis plant to complete this cycle depends on the plant’s genetics and, particularly, how it’s grown. In general, growing cannabis indoors produces faster results than growing it outdoors because indoor growers have direct control over how long their plants spend in vegetation and flowering – at least when growing photoperiod strains.

A note on the harvesting process

If only weed was ready to smoke the minute your plants get the chop. Unfortunately, to enhance the flavour, aroma, potency, and shelf life of your buds, you’ll need to trim, dry, and cure them post-harvest.

Of course, the amount of time it takes to trim your weed will vary depending on how many plants you’ve grown and whether you’re facing the job alone or with friends. In my experience, I’ve always been able to trim my plants in a single day, but I’ve never grown more than 3-4 small plants at a time. Larger harvests may take several days (or friends) to trim.

On average, the process of drying cannabis takes about 2-4 weeks, though this can vary greatly depending on the size of your buds and the conditions in your area. Larger flowers contain more moisture and, therefore, will take longer to dry. Meanwhile, dry and warm conditions will speed up the drying process, while cold and humid conditions will do the opposite.

Where I live, for example, we get a lot of rain and high relative humidity at the end of the summer, and I’ve had to wait 3-5 weeks for my buds to dry properly. It’s important you do not try and rush the drying process, as excess moisture in your buds can cause them to rot when you store them in jars for curing.

After drying, you’ll want to cure your buds in glass jars for at least another 2 weeks. Curing helps further regulate the amount of humidity in your flowers and intensifies their aromas and flavours. While your buds can be ready to enjoy after just 2 weeks of curing, you may want to wait 4 weeks for their flavours and aromas to develop further – if you can hold off smoking them for that long, that is.

How long does it take to grow weed indoors?

Most indoor cannabis growers will veg their photoperiod plants for 4-6 weeks. Then, they’ll let their plants flower for roughly 8-12 weeks, depending on the genetics they are growing. In turn, an entire indoor grow will generally look something like this:

1. Germination and seedling phase: 2-4 weeks

Cannabis seeds usually take 1-7 days to germinate and, in optimal conditions, will develop their first true leaves within 2-3 weeks of germination.

2. Vegetative phase: 4-8 weeks

Growers will usually keep their plants under a vegetative light cycle (16-18 hours of light and 6-8 hours of dark) for 4-6 weeks. Growers who use training techniques, however, may want to give their plants 8 weeks of veg time to recover from the stress of these techniques before flowering.

3. Flowering phase: 8-10 weeks

The length of this phase varies greatly depending on the kind of genetics you’re cultivating. Since the 1990s, most cannabis seeds have been bred with the indoor grower in mind. Hence, modern strains tend to have fairly short flowering times averaging around 8-10 weeks. However, some sativa varieties can take 12 or more weeks to mature.

4. Trimming, drying, and curing: 4-6 weeks

As we mentioned above, the length of this process can vary depending on the weight of your harvest, the size of your individual flowers, and the conditions in your local area.

Total average time from seed to harvest indoors: 18-28 weeks (4.5-7 months)

How long does weed take to grow outdoors?

Generally, growing weed outdoors takes longer than indoors – not because outdoor plants go through any extra stages of life, but simply because you won’t have any control over when your plants start flowering.

On average, outdoor growers will sow their seeds in spring and harvest their weed in autumn. In the Northern Hemisphere, for example, growers will typically sow their seeds in March and chop down their plants in October. In the Southern Hemisphere, on the other hand, growers will sow their seeds around September and harvest their flowers around April.

Here’s a more detailed look at what the cannabis grow cycle generally looks like outdoors:

1. Germination and seedling phase: 2-4 weeks

Same as indoors, as outdoor growers usually start their seedlings off inside on a windowsill or using a propagator. Months: March (Nth) / September (Sth)

2. Vegetative phase: 12 weeks approx.

Once your plants have developed their first true leaves, you’ll want to start acclimatising them to the conditions outdoors. This process may take a few days, as you can’t just pop young cannabis plants into full outdoor sun from one day to another. Instead, you’ll want to bring them outside and accustom them to the heat and sun gradually. Months: April – June (Nth) / October – December (Sth)

3. Flowering phase: 12- 14 weeks approx.

Outdoor cannabis plants will start flowering after the summer solstice. The exact amount of time it takes for cannabis plants to finish flowering outdoors varies greatly depending on their genetics and local conditions. Months: July – October (Nth) / January – April (Sth)

4. Trimming, drying, and curing: 4-6 weeks

Same as indoors.

Total average time from seed to harvest outdoors: 30-34 weeks (7.5-8.5 months)

A note on growing autoflowers

Note that the grow times we’ve outlined above are for photoperiod strains, which take notably longer to grow than autoflowers. Some autoflowers, like our Sticky Orange XXL, for example, can go from seed to harvest in just 10 weeks indoors or outside.

Autoflowering seeds have been bred using Cannabis ruderalis, a variety of cannabis that flowers automatically based on age rather than in response to light cycle changes. Autoflowers, therefore, typically veg for 2-4 weeks, then automatically transition into their bloom phase which, in the case of Sticky Orange XXL for example, can last just 45-50 days (6.5-7.5 weeks).

Factors that affect the speed at which cannabis plants grow

Remember, the growth cycle timelines we outlined above are designed to give beginner growers a rough understanding of how long it generally takes to cultivate cannabis indoors or outside.

In reality, however, there’s a number of factors that can influence the length of a grow. These include:

1. Genetics

Indica plants, in general, will tend to have a faster flowering time than sativas. That’s because they originate from and have adapted to regions with shorter summers. Meanwhile, autoflowering strains, as we mentioned above, are renowned for the speed they inherited from their ruderalis predecessors.

2. The environment

Of course, plants growing in optimal conditions are going to grow faster than plants growing in a sub-par environment. Environmental stressors like cold or hot temperatures, high or low humidity, or strong winds will stunt the growth of vegetative plants and inhibit the development of buds in flowering plants.

3. Stress

Like humans, cannabis plants suffer from stress too. Some common stressors to cannabis include

Pests and pathogens.
- Over or underwatering.
- Over or underfeeding.
- Physical damage (such as braking branches).
- Training; All training techniques stress plants to some degree.

Note: If your photoperiod plants suffered from stress during their vegetative growth phase, you’ll want to let them recover before flipping them to bloom, which ultimately adds more weeks to your grow calendar.

Tips for a speedy cannabis harvest

Got a need for speed? You’re not alone –every cannabis grower wants to get to harvest with as few complications and setbacks as possible. To ensure your next harvest is as timely as possible, we recommend you:

Pick the right genetics

Start your grow off right by picking strains with growth times that suit your growing style and expectations. For example:

Sticky Orange XXL and Gorillaz are two autoflowering strains that deliver mouthwatering harvests after just 40-50 days of flowering (roughly 10 weeks after germination in total). If it’s speed you’re after, there’s no beating these two autos.

Blue Sunset is a hybrid cannabis strain that our expert breeders created in combination with Sherbinskis – the creators of Sunset Sherbet and Gelato. Stemming from Buffalo Blue x Blue Satellite 2.2 x Runtz, this candy-sweet indica-dominant plant has a 50–60-day flowering period, ideal for growers looking for a plant with an average grow speed.

As her name implies, White Gorilla Haze combines genetics from the US classic Gorilla Glue and two all-star Haze cuts – Amnesia Haze and Silver Haze. And while she can take 65-80 days to mature fully, her frosty flowers, complex earthy pine aroma, and incredible potency are well worth the wait!

Time your training properly

Planning to train your plants? The right mix of LST and HST techniques can help you push your plants to their limits and produce extra-large harvests. However, improper training can stress your plants which may stunt their growth, delay their flowering, and push back your harvest date.

When training your plants remember:

To start training early in the veg cycle, giving your plants time to recover from any stress before they enter bloom.
To read up on how to properly train your plants. Proper technique is vital to ensure your training techniques actually have the desired effect.

Create the perfect environment

Growing your plants in optimal conditions is the best way to ensure you get to harvest on time. Of course, this is much easier indoors than outdoors, where your plants are at the mercy of local weather conditions.

To provide your plants with the best possible conditions, make sure:

Your temperature and humidity levels are on point.
Check out our article on cannabis heat stress to learn all about the ideal temperature and humidity for cannabis throughout the plant’s various stages of life.
To ventilate your grow space. Check out our article on proper ventilation in indoor grow tents for more information.
You grow your plants in the best medium, such as high-quality soil. Learn about the best soil for growing cannabis here.
Water and feed your plants with care. With a solid watering and feeding routine, your cannabis plants will have all the nutrients they need to thrive. For more information on watering and feeding weed, check out this article on how to water your cannabis plants properly.
Stave off pests and pathogens. A good defence is always the best offence against pests and will help ensure you harvest your cannabis plants on time. Click here to learn how to prevent cannabis pests outdoors.

Got your own tips and tricks for a smooth and timely cannabis harvest? Share them with us and our readers below!

Disclaimer:
Laws and regulations regarding cannabis cultivation differ from country to country. Sensi Seeds therefore strongly advises you to check your local laws and regulations. Do not act in conflict with the law.

How Long Does It Take to Grow Weed?