Knowing where your cannabis plants are in their life cycle will dictate when to prune, train, and harvest your plants. Learn more about marijuana growth stages today. It typically takes between 3-4 months to grow weed. Let’s take a look at the question of how long does it take to grow weed and the time needed for each step. Good weed comes to those who wait. But just how many months do you need to grow cannabis, and when can you harvest your first yield?
4 stages of marijuana plant growth
Cannabis plants go through a series of stages as they grow and mature, and those different growth stages call for different amounts of light, nutrients, and water.
It’s important to know these stages and how long each lasts to know what the plant needs and when. Knowing where your cannabis plants are in their life cycles will dictate when to prune, train, and trellis your plants, and when to harvest.
How long does it take to grow a marijuana plant?
Generally speaking, it takes anywhere from 10-32 weeks, or about 3-8 months, to grow a weed plant from seed to harvest. It’ll be quicker if you start with a clone or an autoflower seed.
The biggest variability in how long a marijuana plant takes to grow will happen in the vegetative stage—after the seedling phase and before flowering.
If you’re growing indoors, you can force a weed plant to flower after only a few weeks when it’s small or after several weeks when it’s big.
When growing outdoors, you’re at the whim of the seasons and will have to wait until the sun starts to go down in the fall for plants to flower, and then to harvest.
However, one way outdoor growers can control the flowering cycle is by using light deprivation techniques.
What are a weed plant’s growth stages?
The growth stages of marijuana can be broken down into four primary stages from seed to harvest:
- Germination (3-10 days)
- Seedling (2-3 weeks)
- Vegetative (3-16 weeks)
- Flowering (8-11 weeks)
Cannabis seed germination
Seed germination length: 3-10 days
Marijuana light cycle: 18 hours a day indoors; full, direct sun 6 hours a day outdoors
The first marijuana plant stage begins with the seed. A cannabis seed should feel hard and dry, and be light- to dark-brown in color. An undeveloped seed is generally squishy and green or white in color and likely won’t germinate.
Once your seed has germinated, or sprouted, it’s ready to be placed in a growing medium, like soil. The tap root will drive down while the stem of the seedling will grow upward.
Two rounded cotyledon leaves will grow out from the stem as the plant unfolds from the protective casing of the seed. These initial leaves are responsible for taking in sunlight so the plant can grow healthy and stable.
As roots develop, the stalk will rise and you’ll begin to see the first iconic fan leaves grow, at which point your cannabis plant can be considered a seedling.
Can you speed up the germination process?
No. Cannabis seeds are delicate and don’t like to be moved around. They need a warm environment that doesn’t fluctuate in temperature, and not too much water. Once you put them in soil, we recommend leaving them be.
Quality seeds typically have high germination rates, but you may get some duds that don’t sprout. Let them do their thing; helping them along can decrease their chance of survival.
Seedling stage in cannabis plants
Seedling stage length: 2-3 weeks
Marijuana light cycle: 18 hours a day indoors; full, direct sun 6 hours a day outdoors
When your marijuana plant becomes a seedling, you’ll notice it developing the traditional cannabis fan leaves. As a sprout, the seed will initially produce leaves with only one ridged blade.
Once new growth develops, the leaves will develop more blades, or “fingers” (3, 5, 7, etc.). A mature cannabis plant will have between 5 or 7 blades per leaf, but some plants may have more.
Cannabis plants are considered seedlings until they begin to develop leaves with the full number of blades on new fan leaves. A healthy seedling should be a vibrant green color.
Be careful to not overwater the plant in its seedling stage—its roots are so small, it doesn’t need much water to thrive.
At this stage, the plant is vulnerable to disease and mold. Keep its environment clean and monitor excess moisture. Be sure to give it plenty of light.
Even if growing outdoors, a lot of growers will start their seeds inside under an artificial light to help them through this delicate stage of marijuana growth.
If you buy a clone from a grower or breeder it will be a seedling, so you can skip the seed germination phase.
Vegetative stage in cannabis plants
Vegetative stage length: 3-16 weeks
Marijuana light cycle: 18 hours a day indoors; full, direct sun 6 hours a day outdoors
The vegetative stage of cannabis is where the plant’s growth truly takes off, and it typically lasts 3-16 weeks. At this point, you’ve transplanted your plant into a larger pot and the roots and foliage are developing rapidly. This is also the time to begin topping or training your plants.
Be mindful to increase your watering as the plant develops. When it’s young, your plant will need water close to the stalk, but as it grows the roots will also grow outward, so start watering further away from the stalk in the soil so roots can stretch out and absorb water more efficiently.
Vegetative plants appreciate healthy soil with nutrients. Feed them with a high level of nitrogen at this stage.
Cannabis plant flowering stage
Flowering stage length: 8-11 weeks
Marijuana light cycle: 12 hours a day indoors; full, direct sun 6 hours a day outdoors
The flowering stage is the final stage of growth for a cannabis plant. This is when plants start to develop resinous buds and your hard work will be realized. Most strains flower in 8-9 weeks, but some can take even longer, especially some sativas.
Outdoors, flowering occurs naturally when the plant receives less light each day as summer turns into fall.
Indoor growers can trigger the flowering cycle by reducing the amount of light marijuana plants receive from 18 to 12 hours a day.
There are three subphases of the flowering stage:
- Flower initiation (week 1-3): The plant will continue to grow and females will develop pre-flowers—pistils, or white hairs, will grow out, which are the beginnings of buds.
- Mid-flowering (week 4-5): The plant itself will stop growing and buds will start fattening up.
- Late flowering/ripening (week 6 and on): Trichome density will increase and plants will get very sticky; keep an eye on the color of the pistils to tell when to harvest.
There are a number of changes to consider once plants go from the vegetative stage to the flowering stage:
- Don’t prune when plants are flowering, as it can upset their hormones
- Plants should be trellised or scrogged so buds will be supported as they develop and air can flow through plants
- Consider giving plants bloom or phosphorus nutrients
What does the pre-flower stage look like?
Pre-flowers are the beginnings of cannabis plant sex organs. If you’re growing regular seeds, you’ll likely have a mix of male and female plants and will need to determine the sex of your plants to discard the males. It’s imperative to separate males so they don’t pollinate the females.
Pre-flowers appear at the nodes of the plant, where a branch grows out of the main stalk. Females will develop an oval-shaped bract with hairs or pistils sticking out, while males will develop round pollen sacs.
Learn more about pre-flowers and cannabis plant sexing in our anatomy article.
How to tell when a cannabis plant is ready to bloom
When growing outdoors, weed plants will start flowering, or blooming, after the summer solstice, when the daily amount of light starts to decrease. Plants will start developing pre-flowers, as mentioned above, telling you that flowering has initiated.
When growing indoors, growers make the decision to force blooming or “flip” plants into flower by cutting off the amount of artificial light they receive.
What to do when cannabis plants flower early or late
The amount of time it takes a plant to finish, or be done flowering and ready for harvest, will depend on what strain it is. Typically, indicas finish flowering early and sativas finish flowering late.
Note information from the breeder when you buy seeds to grow to get a sense of how long it takes to flower. You may have to harvest some plants early and some late depending on their finish times.
For late-flowering strains, keep an eye on the weather and make sure cold weather doesn’t ruin your plants before they finish.
When do buds grow the most?
Buds typically grow the most toward the end of the flowering life cycle. You probably won’t notice much budding out at the beginning of the flowering stage, and it will slow down toward the end of the cycle, when buds become fully formed.
Once buds have reached full maturation, it’s time to harvest your marijuana. How long it takes to harvest buds depends on many factors, including harvesting methods and how many plants you harvest.
How long can a marijuana plant live?
Weed plants are annuals, meaning they grow and live for one season and then die. Wild cannabis plants grow seeds and drop them when they die, which will grow into new plants the following year.
When harvesting, plants are cut down and die in order to get their buds. New seeds need to be planted in order to grow more plants.
If left unharvested, weed plants will eventually wither and rot within a few months after the peak flowering phase.
When should you grow marijuana?
If you’re growing outdoors in the Northern Hemisphere, growers usually get their seeds between February and April and start germinating seeds by the end of April.
Many start growing seedlings inside in a more controlled environment because seedlings are more delicate, and then put the seedlings in the ground outside once they’re a little bigger and the weather is warmer.
If you’re growing clones or autoflowers, you have a grace period of another month or so. Plants usually need to be outside, in the ground, by the end of June.
Harvesting happens sometime between September and November. This depends on your local climate, as well as the weather that particular year—one year it could be the end of September, the next, end of October; growers in the Pacific Northwest will have to pull down their crops earlier than those in Northern California because of cold weather.
If you’re growing weed indoors, you can grow whenever you like. Keep in mind that the outside environment will affect your grow space—you may need to add heaters in the winter or fans and ACs in the summer.
Other than that, you can start seeds whenever you like and flip them into flower whenever you like, depending on how big you want the plants.
Important dates for growing marijuana outdoors
Many growers begin germinating seeds as early as February and March in order to have big plants come harvest time, but the Spring Equinox is a good reminder that it’s time to kick off the outdoor growing process and start germinating your seeds if you haven’t already.
Many farmers wait until after Mother’s Day in May to put their plants outside. Just make sure all of your plants are outside by the Summer Solstice at the latest.
The weather will start to turn and the sun will begin descending in the sky as your plants fatten up with sweet, sticky buds. It might be tempting, but the Fall Equinox is about when to start harvesting. It’ll depends on your climate and the year—it could happen a little before or after.
Everything should be cleaned up, dried, and curing by Thanksgiving, and in some places, even by Halloween.
As winter approaches, it’s prime time to make your own cannabutter, topicals, or tinctures with all that trim from the harvest. Kick your feet up, relax, and hunker down for the cold, it’s been a long growing season!
Notes on marijuana growth phases
We can’t stress enough that the timeframes in the above graphic are ranges of time for the Northern Hemisphere. You’ll need to adjust them based on your specific region and local weather and climate.
Be sure to keep a grow journal to track the progress of your plants. Looking back on your notes will help you learn from mistakes and maximize the quality and quantity of your buds next year.
Take meticulous notes on when and how you perform each step, noting:
- How much water you give plants, and at what intervals
- Nutrient amounts
- When you top and prune
Pictures will also give you a better sense of how your plants look along the way.
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. 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. 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 seeds (1 day to 4 weeks) (12 hours to 8 days)
- 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)
Step 1: Getting your weed 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.
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. 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.
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. 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. 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. 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.
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 its time to begin flowering.
How long does it take to grow cannabis?
Good weed comes to those who wait. But just how many months do you need to grow cannabis indoors?
The average time for most indoor cannabis plants is roughly four months, but that could fluctuate depending on dozens of factors.
While it’s tough to say when your cannabis strain will mature, you could get a general timeline by reviewing marijuana’s primary stages of development. New growers should get comfortable with these phases to monitor their plant’s progress and schedule their time.
From germination to recreation: the average life cycle of cannabis plants
Traditionally, cultivators recognize four distinct phases in a cannabis plant’s life cycle before harvesting:
- germination: 1-14 days
- seedling: 2-3 weeks
- vegetation: 2-8 weeks
- flowering: 8-10 weeks
You could, however, eliminate the germination and seedling phases if you start with clones rather than seeds. In this overview, we’ll assume you’re beginning with a batch of healthy, feminized seeds.
It also assumes that the seed you have chosen is photoperiod sensitive, meaning that it’s flowering cycle is driven by how much light the plant is exposed to.
1. Germination phase: get your seeds going
You could plant cannabis seeds directly in soil, but most cultivators prefer coaxing out taproots before putting seeds in their growing medium.
Establishing these first roots gives cannabis seeds extra strength during the delicate seedling phase. It also allows growers to “weed out” any weak seeds beforehand rather than wondering whether they’d take root in soil.
The simplest way to jump-start germination is to wrap seeds in a slightly damp paper towel and cover them with a plate. You could also place seeds in a glass of purified water. The important thing is to keep these seeds far from light.
You also should take extra care to avoid contaminating seeds with your fingers. Some cannabis cultivators use tweezers to avoid any unintentional cross-contamination.
Usually, you’ll see white roots sticking out of your seeds in less than one week. There are some rare cases where it could take longer than two weeks, but you probably shouldn’t wait any longer than 14 days.
Monitor your seeds every day for signs of progress, and place them in starter pods once they show signs of development.
2. Seedling phase: growing baby buds
Seedlings should be ready to transplant into your main soil pot after two to three weeks (Shutterstock)
As your cannabis seedlings first reach for life, they will be incredibly fragile. During this early stage, you must use gentle lighting like a dimmed LED or a CFL bulb for 16 hours per day. 1
You should also only mist your cannabis seedlings with pH-corrected water.
Initially, seedlings will have tiny rounded leaves called cotyledons. However, as your plant grows, you should notice the true “cannabis” fan leaves emerge. Generally, people know they’ve transitioned from seedling to vegetation by the number of leaves on their plants.
When you see about four sets of about five fan leaves, your plant should be strong enough to transition to a larger pot. Typically, your seedlings should be ready to transplant into your main soil pot after two to three weeks.
3. Vegetation phase: time to flourish
The vegetation phase is all about growth. During this stage, your plants will rapidly reach upward and grow many stems and fan leaves. To help fuel this growth, vegetative plants need extra nitrogen in their feeding schedules. 2
Arguably, lighting is the most consequential element during vegetation. Since cannabis is a photoperiod plant, it will transition to flowering when you limit the daily amount of light. 3
Interestingly, you could transition from vegetative to flowering any time you want. There’s even a training technique called Sea of Green that takes advantage of this biological feature.
The downside of transitioning out of vegetation early is you’ll have fewer buds. By giving the cannabis plant plenty of time to grow, you’ll enjoy more bud sites, and thus a higher return. If you learn training techniques like bending or topping, you’ll increase your total yield even further.
To keep your strains in vegetation, you need to maintain a light schedule of at least 18 hours on. You could keep this going for as long as you want, but most strains are ready to switch after four to eight weeks. It all depends on how strong your flowers are growing, what strain you’re using, and what kind of yield you want.
4. Flowering phase: see the ‘fruits’ of your labor
In preparation to begin producing flowers, cannabis plants can double their size during early flowering (Shutterstock)
To transition from vegetation to flowering, you need to flip your light schedule from 18/6 to 12/12. The shortening of daylight hours mimics the natural seasonal change from summer to fall and triggers major changes in the plant’s hormones. 4
This causes the plant to shift its focus from growth and development of roots and shoots to the production of pistils as the female plant awaits pollination, which in nature would result in the eventual production of seeds before the plant dies during the winter.
Monitoring flowering plants is similar to vegetation, but you’ll need to transition to flowering nutrients and slightly lower your ambient temperature (~ mid-70s F). You also have to be extra vigilant for signs of mold or hermaphroditism during flowering.
You can determine the sex of a cannabis plant during flowering by looking at the nodes. Male plants have ball-shaped pollen sacs, while females have thin pistil-like strands. If you have a hermaphrodite, it will have both of these features, which means the pollen could disrupt bud production.
The length of the flowering stage largely depends on your strain’s average grow time. The only way to know when to harvest buds is to monitor their size and the color of their trichomes.
For most strains, it takes eight weeks to go through flowering, but it could easily last an additional two or three weeks with sativa strains.
It’s also important to consider that even though this stage is called flowering, that doesn’t mean the plants will solely concentrate on making buds. In preparation to begin producing flowers, plants can double their size during early flowering, so plan your grow space accordingly.
When’s a good time to harvest cannabis?
There’s no set time you should harvest buds from a flowering plant. Instead, you have to rely on your sense of sight to choose when’s a good time to clip your nugs.
Using a high-quality magnifying glass or a jeweler’s loupe, take a close look at the trichomes on each of your buds. Cultivators usually want most of these trichomes to have a milky-white, opaque appearance.
Clear trichomes are too young, and they will have minimal THC concentration. On the opposite extreme, orange-haired trichomes contain an oxidized form of THC known as CBN. 5 While some people enjoy CBN’s supposedly sedating effects, most prefer to clip their nugs when most trichomes are milk-white.
Want professional-quality cannabis? You’ll need patience!
Cultivators could use a few tricks to speed up the growing process, but most feminized seeds will take roughly four months to reach maturity. If you’re an impatient cultivator, you could opt for feminized autoflowering seeds, but remember these cultivars have a lower overall yield and often lower cannabinoid production.
For those not keen on the tradeoffs associated with autoflowers, consider starting with clones or focusing on indica strains to shave off significant time from your schedule. On average, indicas reach full-flowering weeks before sativa strains.
As a final tip, growers should research their preferred cannabis strains in online growing forums. Each hybrid has a unique growing pattern, and there’s a wealth of strain-specific information now available online. Knowing the estimated time for your cultivar is the best way to get an accurate read on how long it will take to grow cannabis.