Ultimate Guide-How Long Does It Take To Grow Weed?

How long does it take to grow weed is a very commonly asked question. Usually it takes about 3-4 months to grow the average cannabis plant – but with the right tools and strategy, you can grow the weed plant you want in as little as 8 weeks.

However, the timeline can vary significantly depending on the cannabis strain you choose, as different strains can influence the overall cultivation period and growth stages.

Let’s take a look at the question of how long does it take to grow weed and the time needed for each step.

How Long Does it Take to Grow Weed – Growing Timeline

The timeline below lays out a seven-stage process of a typical grow schedule. If you’ve been searching online for “how long does it take to grow weed?” you’ve likely run into a range of time periods. How fast plants grow depends on several factors, including genetics, environment, and cultivation techniques.

Generally, a marijuana plant can take 14 to 32 weeks to grow, which translates into about four to eight months to grow. This is for growing a marijuana plant from seed.

The length of time it takes to grow a weed plant can be broken down into multiple phases from seed to harvest:

• Getting your equipment (1 day to 2 weeks)
• Getting your clones or cannabis seeds (1 day to 4 weeks). Cannabis seeds are essential for starting the grow, as they determine the genetics and potential of your plants.
• Germinating your seeds (12 hours to 8 days). Seed germination is the initial stage where seeds sprout and begin the germination process. Proper conditions—such as moisture, warmth, and darkness—are crucial for successful seed germination and healthy early growth.
• Seedling phase (1 to 4 weeks)
• Vegetative phase (2 weeks to 6 months)
• Flowering phase (6 weeks to 3 months)
• Harvesting phase (1 to 3 days)

With the right approach, growers can grow plants from seed or clones through each of these stages.

Step 1: Getting Your Growing Equipment = 1 day to 2 weeks

If you know what you are looking for then this could happen quickly. We will help you with this later on as we set up the grow-rooms and do some grows with different styles and grow mediums.

Step 2: Getting Your Clones or Seeds = 1 day to 4 weeks

Getting clones (cuttings from healthy mother plants) is easy to do in areas that allow cannabis cultivation. But in states or countries where it is illegal to grow, obtaining healthy clones can be a challenge.

Seeds, on the other hand, can be ordered on the internet and generally take 2 to 4 weeks before they arrive by mail. Growers can choose between regular, feminized, or autoflowering seeds, each offering different benefits. The type of cannabis seed selected will influence the grow timeline, as autoflowering seeds flower automatically and typically have a shorter cycle compared to photoperiod strains.

Step 3: Germinate The Seeds = 12 hours to 8 days

If starting with clones this can be skipped. The average time to germinate is 2 or 3 days. Make sure to check your seeds every day because seedlings can sprout in as little as one day.

During the germination process, it is important to keep the growing medium or soil moist (but not waterlogged) to promote healthy seedling development. Moist soil helps ensure proper growth and successful germination.

You’ll know your seed has germinated when your seed has popped and displays a tap root formation.

Check out our guide on the best method to germinate marijuana seeds using paper towels and water.

Step 4: Seedling Phase = 1 week to 4 weeks

Once again, can be avoided if using clones and not seeds. As your cotyledons begin to take shape,  so will your cannabis leaves in a single leaflet form. Generally, growers can give their seedling a light amount of nutrients after the third set of leaves begins to appear.

Healthy cannabis growth during the seedling stage is crucial, as it sets the foundation for successful development in later stages of the plant's lifecycle.

Step 5: Vegetative Phase = 2 weeks to 6 Months!

Yes, that is correct. This stage in the plants life has a huge fluctuation in how long it needs to take. You, as the grower, hold all the power and get to choose how long this phase is. Vegetative plants respond to environmental conditions such as temperature, humidity, and wind, and can also be shaped by training techniques to optimize their growth.

Once you change the light cycle that the plant receives to 12 hours of light, and 12 hours of darkness per day, the plants will switch to the next phase, which is flowering.

If you want to, you can switch the lights to 12/12 right away and force your plants to flower! The sooner you change to 12/12, the faster your plants will flower, and the sooner you can move on to the next crop.

But, keep in mind, the less amount of time you keep your plants in the vegetative phase, meaning getting at least 18 hours of light per day, the smaller your plants will be, and the less marijuana you will have to use.

If you are concerned with how big your plants will grow, maybe because you only have a small space to grow in, you can grow cannabis that only grows only a few inches tall, and you could even grow it the entire time in a little plastic cup if you wanted to!

Keep in mind that buds do not form for at least 2 to 3 weeks in the vegetative phase when beginning with seeds. During this phase, the plant develops the structures that will later support cannabis flowers, and the number of potential bud sites is established.

Most growers allow their plants to stay in the vegetative stage from a few weeks to a few months so they get big enough and will end up with a sizable harvest. Plants tend to grow larger and develop more bud sites with longer vegetative periods, which leads to bigger yields. Bigger plants produce more buds!

But, many growers choose instead to grow small plants and to harvest more often with smaller yields each time.

We recommend at least 3 weeks or more in the vegetative stage with at least 18+ hours of light each day for optimal yields. Even 24 hours of light per day is sometimes better, with certain strains.

The more light, the more buds!

Keep in mind that cannabis plants usually double in size from vegetative phase to when they are done flowering.

This means it’s sometimes best to change to 12 hours of light and 12 hours of darkness once the plants are one-half the size that you feel your grow room has adequate space for.

During the vegetative phase, you can use a number of cultivation training techniques such as super cropping, crimping, topping, tying, bending, sea of green (SOG), screen of green (SCROG), and trellising to alter the growth, direction, height, and quality of your crop. These training methods can increase the number of bud sites on plants grown, resulting in higher yields.

Autoflowering strains, however, have a different vegetative time period than regular feminized seedlings.

Autoflowering strains will have at least two to three weeks of vegetative growth before they automatically start showing any bud formations regardless of photoperiod.

Step 6: Flowering Phase = 6 weeks to 3 months

In nature, cannabis plants start to flower in the fall months, when they are receiving less light. The decrease in light signifies to the plants they are nearing the end of their life cycle and it's time to begin flowering. Cannabis plants start flowering in response to changes in light cycles, and photoperiod plants require a specific number of hours a day of uninterrupted darkness to start flowering.

Indoors, this action is done by changing the amount of light the plants receive to a schedule of 12 hours of light, and 12 hours of uninterrupted darkness. The plants will require less nitrogen during this time than they have had in the previous vegetative phase.

As cannabis transitions from vegetative growth, it enters the pre flower stage and pre flowering stage, where plants begin to show their sex through the development of pre-flowers at the nodes. This is a critical time to identify whether you have a male or intersex plant, as removing them early prevents pollination and ensures only female plants remain to produce buds.

Most cannabis plants flower for around 8-14 weeks, which is known as the flowering period. Depending on the strain, some may flower a lot longer than others. Pure indica plants usually finish around 8 weeks of flowering, while pure Sativa strains usually finish around 12-14 weeks.

Some Sativa strains have been known to flower for 16 weeks or longer.  For this reason, indica strains are most commonly the kind that is grown indoors.

Most growers like to grow, harvest, sell, and get back at it as quickly as possible to turn a faster profit. If you are not in it for the profit, sativa strains can be fun to grow.

You could let them grow real big and tall if you have the ceiling space or outdoor area for them. Make sure to research the strain you're growing so you have a general idea of the flowering time and the expected flowering stages.

Autoflowering strains can have a short flowering stage and begin to flower after just three weeks. Unlike photoperiod plants, which rely on changes in light schedule to start flowering, autoflowering strains start flowering automatically after a set age. Autoflowering strains can be ready to harvest 5 weeks after. That means that you can grow an autoflowering seed in just eight weeks.

Keep a close eye on any new sex organ formations to determine the sex of your plants within the first two weeks of flowering. During the pre-flowering stage, look for signs of male plants or intersex plants, such as pollen sacs, and remove them promptly.

You will be able to tell whether your male plant needs to be carefully extracted from the grow site or whether you have a female on your hands. Removing male plants is essential to prevent pollination and ensure only female plants produce buds.

It’s important to separate the males from the females to prevent the pollination of females.

Pruning too early into the flowering stage can affect the hormones of the plant and the number of buds produced. Managing bud sites and supporting flowering plants during this time can improve growing buds and overall yield.

Ultimately the flowering phase will depend on the genetics of your strain. The process of bud development and bud growth is crucial during this stage, as proper care and nutrient management will maximize yield and potency.

Fast-flowering strains can grow in a period of between six to eight weeks. Fast-flowering strains include:

• Girl Scout Cookies (GSC)
• OG Kush
• Original Glue (Gorilla Glue #4/GG4)
• Granddaddy Purple (GDP)

A medium flowering growth rate can take between eight to 12 weeks. Most strains will have a medium flowering time. Medium-flowering strains include:

• Sour Diesel
• Wedding Gelato
• Strawberry Lemonade
• Pineapple Chunk.

Long flowering times between 12 and 14 weeks occur in most sativa, landrace, and Haze strains. Long-flowering strains include:

• Colombian Gold
• San Fernando Valley OG
• Chocolate Thai

Environmental factors such as stress or incorrect light schedules can cause cannabis plants to flower early, so maintaining stable conditions is important for healthy bud development and optimal harvest.

Step 7: Harvesting = 1 to 3 days

Harvesting times can vary depending on your strain’s height, yield, and overall quality, as well as your experience with drying, curing, and trimming. To determine the right harvest time, closely examine the growing buds for signs of maturity, such as pistil color and trichome clarity.

Quality cannabis buds can dry in about four days but usually take a week or more for a slow and full drying process. Your bud should be dry enough to avoid mold, but not too dry.

Curing can take anywhere from a couple of weeks to a little over a month. Some users may leave their cannabis curing for up to two months or even six months for some strains. The curing process involves storing buds in airtight containers and periodically burping them to enhance flavor, potency, and prevent mold.

Curing is another long and slow process intended to maximize the effects of your bud, especially for medical users.

Trimming times can depend on your experience. Of course, hand trimming will be more time-consuming than using a commercial and automatic trimming machine. How many plants you have will also affect the time and effort required for trimming and drying, as larger harvests require more work at each stage.

How Long Does It Take To Grow Weed? Why the Answer Isn't Simple

One of the most common beginner questions is: how long does it take to grow weed? The truth is, there isn’t one single answer. A cannabis plant’s timeline is shaped by genetics, environment, growing medium, and the choices the grower makes along the way.

Cannabis growers use different strategies for growing indoors and growing outdoors, which impacts the overall cannabis growth timeline. Growing indoors allows for more control over environmental conditions and can shorten the growth cycle, while growing outdoors depends on natural factors like seasons and climate, often resulting in a longer timeline.

In general:

• Indoor weed: 3–4 months from seed to harvest
• Outdoor weed: 5–7 months depending on the growing season
• Autoflower seeds: 70–90 days regardless of light cycle
• Photoperiod strains: 4–8 months depending on veg and flower time

“Growing cannabis is a partnership with the plant. You can guide and support it, but you can’t rush nature. Patience and consistency are the real secrets to great weed.”— Gavin Kushman, CTU Strain Expert

Stage-by-Stage Breakdown

When people ask, how long does it take a weed plant to grow, they're really asking about each stage. Let's explore them.

1. Germination (2–7 days)

• Seeds sprout their taproot and push toward the surface.
• For growers wondering how long does it take a weed seed to grow roots, the answer is usually within a week if moisture and warmth are steady.

2. Seedling Stage (2–3 weeks)

• Delicate leaves form.
• Plants need gentle light and high humidity.

3. Vegetative Stage (4–12 weeks)

• Explosive growth in leaves and stems.
• Indoor growers can shorten this stage for faster harvest, while outdoor weed plants may veg for months until natural light shifts.

4. Flowering Stage (6–12 weeks)

• Buds form and resin production begins.
• How long does it take weed to grow indoors during flowering? For most photoperiod strains, 8–10 weeks. Autoflowers may finish in 6.

5. Harvest and Curing (2–4 weeks)

• Harvesting is only part of the journey. Drying and curing take another few weeks to achieve smooth smoke and full potency.

Indoor vs. Outdoor Timelines

Indoor Weed

• Faster turnaround because growers control light cycles.
• How long does it take to grow indoor weed? Around 100–120 days from seed to jar.
• Hydroponic systems can cut time further.

Outdoor Weed

• Seasonal — seeds planted in spring finish in late summer or fall.
• How long does it take weed to grow outdoors? Typically 150–180 days.
• Larger plants, often higher yields, but subject to weather and pests.

How Long Does It Take to Grow Weed From Seed?

From seed to smoke, expect 4–8 months depending on method. Autoflowers shorten that window dramatically:

• How long does it take to grow weed from seed indoors? Roughly 3–4 months.
• How long does it take to grow a weed seed outdoors? Around 6 months from planting to curing.

Factors That Change the Timeline

1. Genetics
2. Indicas: faster growers, shorter flowering times.
3. Sativas: taller, often need 12+ weeks of flowering.
4. Autoflowers: complete cycle in ~70 days.
5. Indicas: faster growers, shorter flowering times.
6. Sativas: taller, often need 12+ weeks of flowering.
7. Autoflowers: complete cycle in ~70 days.
8. Environment
9. Indoor = controlled, quicker.
10. Outdoor = seasonal, slower, but bigger yields.
11. Indoor = controlled, quicker.
12. Outdoor = seasonal, slower, but bigger yields.
13. Medium
14. Hydroponics accelerates growth.
15. Soil grows take longer but are more forgiving.
16. Hydroponics accelerates growth.
17. Soil grows take longer but are more forgiving.
18. Grower Skill
19. Beginners often extend the cycle due to mistakes.
20. Experienced growers can hit target timelines more reliably.
21. Beginners often extend the cycle due to mistakes.
22. Experienced growers can hit target timelines more reliably.

How Long Does It Take Weed Plants to Grow Big?

If you're chasing size:

• Indoors: veg for 2–3 months and train plants with topping or SCROG to maximize yield.
• Outdoors: with a full season, plants can reach 6–10 feet tall and yield pounds.

Step-by-Step Beginner Roadmap

1. Choose Seeds: Photoperiod or autoflower.
2. Set Up Space: Indoor tent with lights, or outdoor plot with sun.
3. Germinate Seeds: Paper towel, water glass, or soil method.
4. Seedling Care: Small pots, gentle lighting, humidity dome if needed.
5. Vegetative Growth: 18–24 hours of light indoors, proper nutrients, training.
6. Flowering: 12/12 light indoors, or wait for shorter days outdoors.
7. Harvest: Use a jeweler's loupe to check trichomes (cloudy/amber).
8. Drying & Curing: 7–10 days of drying, then cure in jars for 2–4 weeks.

Plant Care and Maintenance

Proper care and maintenance are the foundation of healthy cannabis plants and successful cannabis cultivation. During the vegetative stage, your plants are focused on building strong roots, sturdy stems, and lush foliage—setting the stage for robust bud production later on.

For indoor growers, providing the right hours of light is essential. Most cannabis strains thrive with 18 to 24 hours of light per day during the vegetative stage, which supports rapid growth and helps young cannabis plants develop a dense canopy.

Make sure your grow space has proper air circulation and maintains a stable temperature and humidity to prevent issues like mold or excess moisture.

Outdoor growers should select a spot that receives at least 6 hours of direct sunlight daily. The more sunlight your cannabis plants get, the more energy they have for healthy growth. Keep an eye on your local climate and be prepared to protect your plants from extreme weather or pests.

No matter where you grow, a balanced nutrient regimen is key. During the vegetative phase, cannabis plants need higher levels of nitrogen, along with phosphorus and potassium, to fuel their vigorous growth. Water your plants when the top inch of soil feels dry, and avoid overwatering to keep roots healthy.

By paying close attention to your plants’ needs—light, nutrients, water, and environment—you’ll set the stage for a thriving cannabis grow and maximize your harvest when flowering begins.

Common Mistakes That Delay Growth

• Overwatering seedlings
• Using poor genetics
• Harvesting too early
• Inconsistent light cycles indoors
• Pest infestations outdoors

Special Cases

• How long does it take to grow weed inside hydroponically? Often 90 days from seed to harvest.
• How long does it take for weed to grow outdoors in tropical climates? Year-round grows possible, but mold and humidity are risks. The summer solstice marks the point when daylight hours begin to decrease, signaling the end of the vegetative stage and the start of flowering for outdoor marijuana plants.
• How long does it take weed to grow in greenhouses? Typically 4–6 months with hybrid benefits of indoor control and outdoor sun. In certain conditions, a marijuana plant can live for multiple years, but it is usually cultivated as an annual for harvest.

Frequently Asked Questions : How Long Does it Take To Grow Weed?

How long does it take to grow weed indoors from seed?

About 3–4 months, depending on strain and training methods.

How long does it take to grow a weed seed into a mature plant?

Anywhere from 70 days (autoflower) to 8 months (sativa outdoors).

Is outdoor weed slower than indoor?

Yes, outdoor weed plants rely on seasonal light, while indoor plants can be harvested multiple times a year.

What's the shortest grow time possible?

Autoflowers in hydroponics can finish in ~70 days.

Can I force plants to grow faster?

You can shorten veg indoors, but rushing flowering reduces yield and potency.

How long does it take to grow weed that's ready to sell?

Commercial operations typically run 3–5 month cycles indoors, or one large outdoor harvest per year.

15 Interesting Facts About Growing Weed

1. Most cannabis strains require a light cycle change to induce flowering, generally using a 12/12 light schedule.
2. The total duration for autoflowering strains is 2 to 3 months, while photoperiod varieties can take 4 to 8 months outdoors.
3. The vegetative stage of cannabis growth lasts from 4 to 16 weeks but is typically around 4 to 8 weeks for indoor grows.
4. Outdoor cannabis plants are generally ready to harvest in mid-to-late autumn, depending on the local climate and conditions.
5. The vegetative phase for indoor cannabis typically lasts 4-8 weeks, while outdoor plants may have a much longer vegetative period due to acclimatization.
6. Outdoor growers generally start planting in spring and harvest in autumn, while indoor growers can start any time.
7. Nutrient levels, especially nitrogen during vegetative growth and phosphorus and potassium during flowering, influence cannabis plant health and yields.
8. Training techniques can enhance light exposure to lower branches, promote bushier growth, and ultimately increase yields.
9. Monitoring and managing pests and diseases throughout the growth cycle is essential for maintaining plant health and preventing losses.
10. The drying process should ideally be a slow process to preserve potency.
11. Curing cannabis usually takes 2 weeks to over a month.
12. Excess residual moisture increases the risk of mold growth during curing.
13. Proper curing can minimize harsh tastes and enhance smoothness of smoke.
14. Buds should be dried in a controlled environment with humidity around 50%.
15. Trimming cannabis is a necessary step prior to drying and curing.

How Long Does It Takes To Grow Weed-Recap

The strain you're growing, the cultivation technique, and the environmental circumstances can all have a big impact on how long it takes to produce cannabis from seed to harvest.

For some autoflowering strains, the complete growth cycle might take anywhere from 8 weeks to 20 weeks or longer. For some photoperiod strains, the entire growth cycle can take as long as 40 weeks.

The question “how long does it take to grow weed” has dozens of answers. From seedling to smoke, the timeline can be as little as 70 days with autoflowers or as long as 8 months with traditional sativas outdoors.

The best growers focus less on the calendar and more on the signals their plants give. As Gavin Kushman puts it:

“Your plant will always show you what it needs. The real grower's job is listening.”

With patience, preparation, and proper care, growers can master the cycle and produce cannabis they're proud of.