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? 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. When it comes to how long it takes to grow cannabis, there really isn't a simple answer. Learn more about marijuana cultivation as we explore some of the general time-frames for different stages of the cannabis growing process.
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.
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 Plants?
T here are a lot of reasons to give growing your own cannabis a try. Regardless of whether you’d like to grow the herb for medicinal or recreational purposes, tending to your own cannabis plants can be rewarding for weed growing newbies and green thumbs alike, and may even be more affordable in the long run than purchasing marijuana at your local dispensary.
- Growing Marijuana: The Beginner’s Guide
- How to Grow Marijuana for Personal Use and Avoid Dispensaries
- How to Properly Distance Cannabis Plants in a Grow Room
- Closing the Yield Gap for Cannabis: A Meta-Analysis of Factors Determining Cannabis Yield
However, growing cannabis is not exactly like taking care of a potted plant, and one thing a houseplant certainly does not need is a deft hand to guide it through its grow cycles. After all, daisies will bloom if you can at least remember to give them some water and sun. Cannabis? Not so much.
To grow cannabis that can be consumed for its intended purpose, you’ve not only got to lead the plant through its many stages from germination to curing, but your plants require both attention and time. Which begs the logical question, how long does it take to grow marijuana plants? Let’s dig in.
How Long Does it Take to Grow Weed?
The very short answer is – that depends on whether you’re growing indoor, outdoor, greenhouse, coco, or hydroponic weed. Grow times for cannabis plants vary widely, but on average, expect about three-to-five months for indoor grows. However, there are many factors that could add or subtract from that range, including whether you choose to grow from a clone or a seedling, the target yield (how much consumable product) and the growing method you’ve chosen.
A very loose breakdown of a growing timeline could look like this:
Basic Cannabis Cultivation Timeline:
- Seed germination: 1-7 days
- Vegetative stage, when the plant is growing just stems and leaves: three weeks to eight weeks or more
- Flowering stage, when buds start to appear: five weeks to sixteen weeks or longer
- Harvesting, drying, and curing: two to four weeks
But the number one determinant of growing time depends on whether you’re growing sativa, indica, or hybrid cannabis strains. Let’s take a look at some average grow times for each.
Cultivation Time for Different Cannabis Plants
For those looking to grow cannabis more quickly or achieve higher yielding strains, indica is the way to go. With a shorter flowering period – about eight-to-twelve weeks – plus a generally higher end yield, growers often prefer them because they can be cultivated in more frequent cycles indoors, while outdoor growers can time several growing cycles before the weather turns cold.
Another benefit of growing indica seeds is that they tend to grow shorter and bushier than sativas, making them a better fit for indoor setups or growing in a backyard garden.
This cerebral and uplifting cannabis variety poses more challenges than growing indica. In addition to their longer ten-to-twelve week flowering period, plants grown from sativa seeds tend to produce a smaller yield (although this is certainly not true of all sativa strains).
Sativas can also grow to be very tall, up to 20 feet in an outdoor setting, which makes them difficult to conceal from neighbors in an outdoor grow setting. Even when confined inside, they may still grow long and lanky, a challenge for anyone trying to manage a small grow space.
A genetic mix of both indica and sativa strains, the growing time for hybrid marijuana strains may vary depending on which way the genetics lean.
Since hybrid seeds are a true blend of both sativa and indica, cultivators often prefer to grow them because of their higher output, generally faster growing time, and consumer appeal.
On average, hybrids tend to grow faster in the vegetative stage like a sativa, but may have a shorter flowering period like indica, about six-to-ten weeks.
Frequently Asked Questions about Cannabis Plant Growth
What is the fastest you can grow weed?
One seed company says they have a strain that can go from seed to harvest in 49 days. Before you buy seeds from any company, be sure to do your own research on quality and reputability, and make sure you’re getting a strain that suits your consumption habits and preferences.
Is there a way to speed up cannabis growth?
There are a couple of hacks that could speed up cannabis growth, including growing autoflowering hybrids, growing from clones instead of seeds, growing hydroponic weed, and changing up the stressors put on the plant (although this option is probably best left to more experienced growers).
Do you have any experience growing cannabis at home? How long did it take you from seed to harvest? Share your stories in the comments below.
Erin Hiatt is a New York City-based writer who has been covering the cannabis industry for more than six years. Her work – which has appeared in Hemp Connoisseur Magazine, PotGuide, Civilized, Vice, Freedom Leaf, MERRY JANE, Alternet, and CannaInvestor – covers a broad range of topics, including cannabis policy and law, CBD, hemp law and applications, science and technology, beauty, and psychedelics.
Erin’s work and industry insights have been featured on the podcasts The Let’s Go Eat Show, In the Know 420, and she has appeared as a featured panelist on the topic of hemp media. Erin has interviewed top industry experts such as Dr. Carl Hart, Ethan Nadelmann, Amanda Feilding, Mark A.R. Kleiman, Dr. James Fadiman, and culture icons Governor Jesse Ventura, and author Tom Robbins. You can follow her work on LinkedIn, WordPress, @erinhiatt on Twitter, and @erinisred on Instagram.