by Nebula Haze

“I need to harvest weed as soon as possible. What’s the fastest growth method? What can I do to speed up the time to harvest?”

If you want homegrown weed in hand as quick as can be, you came to the right place! Keep reading to learn how to grow the fastest cannabis harvest possible.

Many auto-flowering strains, like this Gorilla Glue Auto, are ready to harvest just 2 months from germination.

How to Speed Up Cannabis Harvest Time

Several readers have written in to ask about speeding up the time to harvest. So, how long does it actually take to grow marijuana?

Short Answer: From Day 1 of your marijuana plant’s life to harvest day, you are looking at a wide window ranging between 2-5 months. Many factors affect the total time, but the average grow takes 3-4 months. This guide shows you how to cut the total time down to a minimum of 2 months to harvest your own weed.

Learn more about the marijuana growth timeline.

With this guide, you could be harvesting homegrown weed in just 2 months!

Where can I buy cannabis seeds?

If you want to increase the amount of weed per plant, on average, you need bigger plants. Bigger plants need extra time to grow. Do you want to grow a few grams, a few ounces, or a few pounds? These yield goals impact your total time to harvest.

There’s a tradeoff between time and yields. Bigger cannabis plants often take more time to grow, but can support more buds.

7 Tactics To Get To Harvest As Quickly As Possible

Faster is not always better, but there are ways that you can speed up the time from cannabis seedling to harvest without sacrificing quality, potency, or yields.

So today I’d like to share a short guide on how you can reduce the time to a marijuana harvest, and how you can reduce the amount of time you actually spend tending your plants, while still getting an outstanding harvest.

As you may already know, the life cycle for all marijuana plants is separated into two parts: the vegetative stage and the flowering stage. Plants grow only leaves and stems in the vegetative stage. Plants grow buds in the flowering stage.

That means, at the core, there are only two ways to reduce your time-to-harvest with cannabis plants.

1. Shorten the vegetative stage
2. Shorten the flowering stage

This article covers both, giving you 7 effective tactics to shorten either one or the other!

Vegetative cannabis only grows stems and leaves.

Cannabis plants start growing buds (flowers) in the flowering stage.

If you’re serious about getting big cannabis yields as quickly as possible, then this article shows you how to shorten each stage to the minimum time while still achieving your goals for yields and bud quality, of course. Let’s get to it!

1.) Choose A Quick-Finishing Strain of Marijuana 

As mentioned above, there are two different types of cannabis strains: auto-flowering and photoperiod. Autoflowering strains are the fastest of all cannabis strains, though there are very fast photoperiod strains, too. Let me break down what you need to know when it comes to picking the “fastest” strain for each type.

Learn more about auto-flowering vs photoperiod strains.

Autoflowering: Which strains achieve the fastest harvest?

Each auto-flowering plant is on a set time schedule from when they germinate, automatically making buds on their own (hence the name). There’s not much you can do to change the time to harvest with auto-flowering strains. What matters is specifically which strain you get.

Most auto-flowering strains are ready to harvest in only 2-3 months from seed germination. Though when you choose a really fast autoflowering strain, you should expect smaller plants (and relatively smaller yields). Why? If the plant doesn’t have time to get big, it won’t be able to support as many buds as a bigger plant.

In the past, auto-flowering strains of marijuana tended to grow buds with milder potency than photoperiod strains. This can be a positive or negative depending on what you’re looking for. However, as of 2025, many auto-flowering strains are now just as potent as their photoperiod counterparts.

Here are some proven quick-finishing auto-flowering strains:

• Girl Scout Cookies Auto by Seed Supreme
• Gorilla Cookies Auto by Fast Buds
• LSD-25 Auto by Fast Buds
• Pineapple Express Auto by G13 Labs
• Purple Lemonade Auto by North Atlantic

Note: If you’re looking for a particular breeder, nearly all auto-flowering strains by Fast Buds are ready to harvest about 2 months from germination (fast strains are their specialty!).

In this auto-flowering grow, I harvested more than 2 ounces per plant in under 3 months

With many autoflower cannabis plants growing at once, even 2 ounces per plant starts to add up!

Photoperiod strains: Which strains achieve the fastest harvest?

As a photoperiod grower, you control the length of the vegetative stage. Regardless of strain. That’s because photoperiod strains stay in the vegetative stage until you “tell” plants to start flowering by giving it “long nights” (at least 12 hours of total darkness each day). This makes the plant “think” winter is coming by simulating long late summer nights. This means you can shorten your total grow time by finding ways to shorten the vegetative stage. A lot of the rest of today’s tutorial is about how to shorten the vegetative stage, and isn’t affected much by strain.

Learn more giving photoperiod plants a 12/12 light schedule so they start making buds.

Did you know? On average, photoperiod cannabis buds are more potent in THC levels.

But strain does affect your time-to-harvest even when growing photoperiod strains. That’s because the length of the flowering stage (the time it takes buds to form and be ready to harvest) is strain-specific. Choosing a fast-flowering strain means your plants spend overall less time making buds before they’re ready to harvest.

Many modern photoperiod hybrids naturally have a short flowering periods of only 6-8 weeks. These strains are sometimes listed as “Fast” or “Express”, or both. Some examples of cannabis buds that are typically ready to harvest in less than 8 weeks after they start flowering are:

• Bruce Banner Fast Version by Seed Supreme
• Crystal Candy F1 Fast by Sweet Seeds
• Honey Cream Fast by Royal Queen Seeds
• Pineapple Express #2 by G13 Labs
• Purple Lemonade FAST by Fast Buds

Hazes and Sativas often take much longer. For example, a true haze strain (like the legendary Neville’s Haze) can take 3+ months in the flowering stage before buds are ready to harvest.

Every different strain has pros and cons, but if time is a factor for you, pay close attention to the length of the flowering stage when deciding which photoperiod strain to grow. The majority of cannabis seed banks list the length of the flowering period as part of the details for each strain.

Learn how to research cannabis strains.

Once you’ve started flowering a specific photoperiod strain, there aren’t a lot of options to speed things up during the flowering stage. Well, there actually is one controversial way to shorten the flowering stage of photoperiod plants, but it also can dramatically reduce yields. I talk about that at the end of this article, but basically it involves giving flowering photoperiod plants longer nights. 

So your main option to shorten the flowering stage is simply to choose a fast-flowering strain. The flowering stage overall is less flexible to “speed up” because it’s strain-dependent. So now let’s talk about what you can do to shorten the vegetative stage, of which there are many techniques!

2.) Grow more, but smaller plants

This strategy is known as the “Sea of Green” technique. Essentially you fill your grow space with many smaller plants, instead of just one or two big plants. A bunch of smaller plants is easy for new growers to manage, plus it gives you the option of trying different strains instead of growing a lot of any one strain.

Autoflowering sea of green (2-3 months to harvest)

These auto-flowering plants were ready to harvest just 2 month from germination. With 8 plants producing an average of 2+ ounces each, the total harvest was over 1 pound.

Why many small plants instead of just 1 big plant?

Let’s say you want to grow a pound of weed, like the example above. Usually you can’t achieve 1 pound per plant unless growing outdoors, when plants have a full grow season from spring to fall, with tons of light from the sun.

Example of a 1 lb plant, grown outdoors (full grow time was 6 months).

Indoors, it’s a lot tougher to achieve a pound per plant. This next photoperiod plant produced only half as much weed, about 8 ounces, and took about 5 months from seed to harvest. Why so long? The grower didn’t initiate the flowering stage until it was already almost 3 months old.

This photoperiod plant took almost 3 months in the vegetative stage to get this big.

The grower initiated the flowering stage. At that point, the plant needed another 2 months before the buds were ready to harvest.

After reaching a large size, this plant then needed 2 months in the flowering stage.

Total grow time: 5 months

I hope this helps illustrate why growing more (but smaller) plants can help you achieve a faster harvest for a particular amount of yields. You can grow more plant mass, more quickly, when growing lots of plants at once.

But autoflowering plants aren’t the only way to do Sea of Green. Even with photoperiod plants, you can create a sea of green by initiating the flowering stage when plants are only about 4 weeks old. That gives you a total time-to-harvest of about 3 months for photoperiod strains with a 2 month flowering period.

Example of a photoperiod “Sea of Green” setup (~3 months to harvest)

Initiate flowering when plants are 4 weeks old…

Two months later you have many plants with just a few big buds. But the yields add up!

The total grow time? Only 3 months. 

Why not just 12/12 from when seeds sprout? Wouldn’t that speed harvest up even quicker? Unfortunately, usually not. If you give 12/12 earlier a photoperiod plant just grows slow and doesn’t start flowering any sooner. Cannabis plants simply are not able to start making buds until they’re 3-4 weeks old, regardless of light schedule.

That’s why it’s not recommended to give your photoperiod seedlings a 12/12 light schedule until they are at least 4 weeks old from germination. Flowering from seed is a very inefficient manner of growing. Plants flowered from seed don’t get enough time to grow many bud sites or structure to allow long buds to form. Learn what happens if you give a photoperiod plant a 12/12 light schedule from germination (also known as “12/12 from seed”).

Don’t give photoperiod plants a 12/12 light schedule from germination, or they stay teeny tiny. You should give them 18+ hours of light a day until they’re at least 3-4 weeks old to maximize your yields indoors. Photoperiod plants won’t start flowering earlier no matter what light schedule they receive, and those extra hours of light when small results in bigger plants with bigger yields. If you need to harvest plants in under 3 months, the only way to achieve that is to grow an auto-flowering strain!

This photoperiod plant got 12/12 from germination, and only produced ~1 gram of weed. Not worth it!

Give photoperiod cannabis 18+ hours of light until they’re 4 weeks old, then initiate 12 12, to maximize yields.

Learn more about growing your own Sea of Green.

3.) Give Plants 24 Hours of Light per Day During the Vegetative Stage

As long as you give your photoperiod plants more than 16 hours of light a day, they will usually stay in the vegetative stage. But if you give the plant more light than that, they have more time in the day to grow.

Light is “food” for plants, and more light is like giving them more energy to grow.

More light per day helps plants grow faster in the vegetative stage, on average.

Some growers don’t agree with the idea of giving plants 24 hours of light a day in the vegetative stage. The idea is it’s better to give marijuana plants 18 hours of light a day max, with a 6 hour dark period during the vegetative stage. And it’s true that cannabis plants grown under 18/6 tend to be more resilient to problems. If you have a sick plant, just reducing the light period and/or light intensity a little bit can help it recover faster.

Regardless, as long as you keep plants healthy, it’s a proven fact that marijuana plants given more than 18 hours of a light a day (up to a full 24 hours of light a day) grow a bit faster during the vegetative stage. However, you may consider backing down to 18/6 if your plant is sick to help it recover from problems faster.

Note: Plants can only conduct so much photosynthesis in a day. If you’re growing with extremely high-intensity lights, your plants are more likely to need a dark period compared to plants grown under lower-intensity lights. Learn more about the plant’s daily light integral (how much light it can use in a day).

Plants given more than 18 hours a day grow faster, as long as you keep them healthy!

Therefore, if a short time to harvest is of the utmost importance to you, you may want to consider going with a longer day, up to 24 hours of light per day. This extra light during the vegetative stage gives the absolute fastest growth. Again, this won’t make the plant’s flowering stage go any faster, but it enables you to start the flowering stage a little bit sooner.

Speaking of ways to get vegetative plants to grow faster…

4.) Consider growing in coco or hydroponics instead of soil

Soil tends to get the slowest vegetative growth rates of any grow medium, especially if plants must get all the nutrients from the soil. Plants that get synthetic nutrients in their water tend to grow significantly faster in the vegetative stage.

So it’s true you can speed soil growth up a bit by giving synthetic nutrients in the water, but if everything is equal, you still achieve faster vegetative growth with a non-soil grow medium.That means that you could speed up time til harvest by using Deep Water Culture (DWC), Coco coir/perlite, or pretty much any non-soil growing medium.

During the flowering stage, the grow medium doesn’t have as much an effect, but choosing a non-soil grow medium can shave weeks off your vegetative stage time (get straight to growing buds sooner!)

Coco is faster than soil. These 5-week old photoperiod cannabis plants are clones grown in identical conditions. The only difference was the top ones were grown in super soil, getting all their nutrients from the soil, while the bottom plants were grown in coco and get synthetic nutrients in their water. Both sets of plants are healthy, yet the coco-grown plants are several inches taller and wider. This isn’t due to grower skill, but just the reality of growing in soil vs non-soil. Check out the full grow journal.

Same age and grow conditions, yet the coco plants are significantly bigger (and bushier) than the soil plants.

Hydro is fastest. In my experience, top-fed Deep Water Culture hydroponics (also called ‘bubbleponics‘) has given me the quickest growth of any hydroponics system I’ve tried.

These hydro plants are only a week older than the above plants, but already big enough to support huge yields when they start flowering.

I love growing cannabis in hydro. It’s a remarkably fun way to grow, and amazingly satisfying to see such fast growth and huge yields! It also tends to take less time once you’re set up, because you don’t have to water plants or remove runoff every few days. You just top off the reservoir when water gets low, which takes seconds.

Learn how to grow cannabis in hydro.

5.) Grow Indoors 

Growing outdoors can be more convenient and vastly cheaper for those who happen to live in a place with great growing conditions since the sun and nature are doing a lot of work for you. But outdoor growing isn’t the fastest way to grow and harvest your crop. (unless growing an autoflowering strain outdoors, since they’re on a set time schedule from germination)

Learn About the “Light Deprivation” Technique for Faster Outdoor Harvests.

Outdoors, you must plant in the spring, and don’t typically harvest until late autumn. If you germinate seed in April and harvest in October, your outdoor grow takes 6 months. Given the right conditions (high-yielding strain, direct sunlight all day, good soil, avoid pests, etc) you can grow huge plants in that time, that produce pounds of buds.

Yet growing indoors gives you the ultimate control over how big your plants get, how long to keep them in the vegetative stage, and exactly when they start flowering amongst other things. You also have a lot more control over how much bud you’ll end up yielding.

With a well-chosen strain and a good setup, one can harvest a pound of photoperiod buds in just 3-4 months indoors. Outdoors, photoperiod harvests almost always take longer.

6.) Pay Attention To Your Plants and Quickly React to Problems

I know this sounds like it doesn’t need to be listed, but it’s a more important job than people think. Every time your plants get sick, it slows down their growth while they try to recover. Every problem your plant runs into can add days or even weeks to your total grow time, or just reduce your yields.

Use our free plant doctor tool to diagnose your sick cannabis plants.

Simply put: fixing all problems quickly equates to a shorter time-to-harvest and/or a bigger harvest.

Plus, by reacting quickly to problems, you will save yourself the stress of trying to deal with a huge problem that’s gotten out of control since you’ve been watching out and adjusting along the way. Problems tend to get much worse when left unchecked.

The more you tend to your plants’ needs, the better they grow, and the faster you get to harvest.

For example, the following plant problems can add time onto your grow

• overwatering, nutrient problems or a pest infestation can dramatically slow down growth, especially for young plants
• heat stress or light burn can not only slow down growth in the vegetative stage, they can prevent buds from maturing properly in the flowering stage
• accidentally re-vegging your budding plants will stop buds from maturing

Learn more about the most common cannabis plant problems right here.

Keep cannabis plants healthy so they grow quickly and flower as fast as possible!

7.) Make Sure You’re Feeding Plants The Right Type of Nutrients During Each Stage of Growth.

In the vegetative stage, it is important that you give your plants the right nutrients needed to get optimal growth.

Learn which nutrients work well for growing weed

Now if you’re starting with a good soil like Fox Farms Ocean Forest soil (a proven choice for growing cannabis), you may not need to supplement any nutrients for the first several weeks, as the nutrients you need are already in the soil. But on average, plants do grow a bit faster if they receive small amounts of synthetic nutrients in the water.

If you’re growing hydroponically (directly in water, or in a soil-less medium like coco coir), it is essential that you provide the nutrients your plant need by delivering nutrients in the water from the beginning.

You’ve probably seen ‘N-P-K’ numbers on the bottles of pretty much every nutrient line there is. These numbers are important to know since cannabis plants use more N (nitrogen) in the vegetative phase, and relatively more P & K (phosphorus & potassium) in the flowering phase. Giving your plant too much N in the flowering phase will actually slow down bud production. This means that you will harvest smaller yields of less-dense buds in addition to waiting longer for said buds.

This is why you need to choose a nutrient system that is specifically formulated for the flowering stage of a plant like marijuana. By providing the right nutrients to your cannabis plants at the right time, you’ll reduce your overall time to harvest and maximize yields.

Learn more about some of the best marijuana nutrient systems here.

Bonus Tip for Photoperiod Strains: Longer Nights in the Flowering Stage

With photoperiod (regular) strains, you can manipulate the light schedule in the flowering stage to get buds to mature faster. Although most plants will start flowering when they get less than 13 or 14 hours of light a day (that’s when plants usually start flowering outdoors), it can take them a long time to “finish” and be ready to harvest with days that long. Some strains won’t make buds while getting that much light a day.

Because of that, it’s typically recommended to give 12 hours of light and 12 hours of dark each day to get a cannabis plant to start flowering. Most strains finish maturing about 7-12 weeks after the switch to 12/12.

Growers typically put grow lights on a timer to give a consistent light schedule every day

Some Sativa and Haze strains are from the equator, and they may take a long time for buds to “finish” under a 12/12 light schedule. In that case, a grower can give a plant longer “nights” to cause the plant to finish flowering faster. In fact, increasing the number of daily dark hours can get almost any strain to finish flowering faster.

Give plants only 10 or 11 hours of light a day to get buds to mature faster

When the days are that short, the plant “thinks” winter is coming quickly and so tries to finish maturing buds as quickly as possible.

One downside is that a shorter flowering stage with less hours of light each day mean that buds get less time to fatten and you end up with smaller yields. Therefore, it’s not recommended to try to get a plant to finish flowering in less than 8 weeks, as you’ll end up with very small yields. This technique is best used if you have a plant that’s been flowering for 2-3 months and doesn’t look like it plans on stopping any time soon.

This technique reduces yields. ​The less light you give your plant overall during its life, and especially in the flowering stage, the less your yields will be in general. A strain that takes longer to finish flowering usually produces bigger yields than a short-flowering strain because it gets so many extra light-hours where it’s making energy and fattening buds.

But I felt like I had to include this information just in case you wondered if there’s a way to speed up the flowering stage for photoperiod plants!

Learn more: Why are my cannabis buds not ready to harvest yet?

How Much Time Per Week Does It Take To Grow Cannabis?

Now that you’re equipped with the information to get you to harvest as soon as possible, let’s quickly address another common question we receive about time.

Growers often write in to ask us how much time it will take per week to grow a marijuana plant. We understand that many of you have busy schedules, and want to know if growing your own weed is a realistic goal for you.

The amount of time spent growing varies greatly depending on the method you use to grow, the size you let your plants get, and the skill of the grower. But that doesn’t mean there isn’t a growing method that’s conducive to spending less time plant-tending.

The truth is, you can grow weed in only 20-30 minutes a week when you use the right techniques and get used to the process of growing. The following article reveals the best way we know to grow lots of potent bud while using a minimum amount of time to do so. We make this happen using a hydroponic style of growing known as Top-fed DWC (aka “bubbleponics”).

Click here to learn more: https://www.growweedeasy.com/high-yield-bubbleponics-technique

Keep in mind that this is a fairly advanced technique, and should only be attempted by intermediate-advanced growers or particularly brave newcomers.

Check out other ways to save time for busy cannabis growers.

Learn More: Why are my cannabis buds taking so long to mature?

About Nebula Haze:

Marijuana has made a positive impact on my life, and I believe every adult should be able to grow the weed they want. I’m dedicated to showing you how easy it can be to grow your own high-grade buds for your medical needs or recreational enjoyment.

I have made it my mission in life to make new and advanced growing information available to anyone on GrowWeedEasy.com.

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