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 cycle 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. 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. If you’re growing outdoors, you’re at the whim of the seasons and will have to wait until the sun starts to go down in fall for it to flower and then to harvest.
When should you grow marijuana?
If you’re growing outdoors in the Northern Hemisphere, growers usually get their seeds between February and April, and you should start your seeds by the end of April. Some growers will start their seedlings inside in a more controlled environment because seedlings are more delicate, and then put their seeds in the ground outside once they’re a little bigger. 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.
Harvest 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, and growers in the Pacific Northwest will have to pull down their crops earlier than those in Northern California.
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
The Spring Equinox is a good reminder that it’s time to kick off the outdoor growing process and start germinating your seeds.
As the sun reaches up high in the sky, your cannabis will want to as well. Make sure all of your plants are outside by the Summer Solstice.
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 wait until around the Fall Equinox to start harvesting.
Everything should be cleaned up, dried, and curing well before the Winter Solstice. Now’s a good 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.
Take meticulous notes on when and how you perform each step, as well as what the weather is like. Other notes can include how much water you give plants, at what intervals, and how much nutrients you give them. Pictures will also give you a better sense of how your plants look along the way.
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)
Seed germination length: 3-10 days
Marijuana light cycle: 16 hours a day
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 needed for the plant to become 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.
Seedling stage length: 2-3 weeks
Marijuana light cycle: 16 hours a day
When your marijuana plant becomes a seedling, you’ll notice it developing more of 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 (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 very 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 length: 3-16 weeks
Marijuana light cycle: indoor—16 hours a day; outdoor—at least 6 hours of direct sunlight (“full sun”), plus several hours indirect sunlight
The vegetative stage of cannabis is where the plant’s growth truly takes off. 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 higher level of nitrogen at this stage.
If you need to determine the sex of your plants (to discard the males), they will start showing sex organs a few weeks into the veg stage. It’s imperative to separate males so they don’t pollinate the females.
Flowering stage length: 8-11 weeks
Marijuana light cycle: 12 hours a day
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 16 to 12 hours a day.
Within the flowering stage, there are three subphases:
- 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 stage, as it can upset their hormones
- Plants should be trellised so buds will be supported as they develop
- Consider giving plants bloom (phosphorus) nutrients
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.
Pat Goggins and Trevor Hennings contributed to this article.
Knowing where your cannabis plants are in their life cycle will dictate when to prune, train, and trellis your plants, and when to harvest. Learn more about marijuana growth stages today.
How Long Marijuana Plants Take to Grow
Are you not sure how long marijuana plants take to grow? Well, the first thing we recommend is to have patience, something that applies to pretty much everything in life. Plants need enough time to grow and develop correctly, and time is what can tell a nice productive plant from a pile of branches lacking in both foliage and yield.
Today we’re going to talk about normal growth times and the different stages that your plants will go through. Maybe some of these questions sound familiar to you;
- How long does cannabis take to germinate/flower?
- What can I do to make my plants flower earlier?
- Can I speed up the growth?
- Which is the fastest, highest yielding plant?
These questions are probably best answered with the age old phrase, time is gold. Obviously a lot of the answers are quite subjective and we can’t give any absolutely concrete times, but we’ll do our best in this article to provide you with a general idea of how long a marijuana plant takes to grow.
Firstly, we’ll begin by dividing the plants’ life cycle into a series of phases:
Germination is defined as the period and process through which the seed changes from a seed to a sapling.
If you’re planting cuttings, then the germination period is known as the cloning and rooting period.
Germination techniques are varying in method, although the one we tend to use the most and is the most recommended involves damp kitchen paper as a base for the seed; many people use other methods, like damp cotton, straight into the earth or a jiffy, or in water.
Some growers even use germination stimulators that work with the seeds initial metabolism and reduce the germination time to about a day in most cases.
Of course, time is relative. It will depend not just on the strain, but the actual quality of the seed itself. Some determining factors are the age of the seed, how fertile it is and how it has been kept.
Saplings tend to take around 24-72 hours to sprout, although sometimes it can take 5 days and in extreme cases it can take up to 15 days. Make sure to pay attention to the water and humidity conditions, as well as the temperature which should be at around 21-24ºC.
This is also called the vegetative phase. It’s the main period of growth that your plant will go through, and probably the most important.
After managing to get your sapling to sprout and transplanting it (into soil or a jiffy), the growth period begins. Just like the name says, your plants will grow the most it’s ever going to grow and stretch upwards during this period, allowing it to get the correct shape and size to proceed to the next stage; flowering.
Like many of you probably already know, your plants will need more light during the growth phase than any other phase. Generally, 18 hours of light and 6 hours of darkness are recommended per day. A proper balance between light and dark is the key element to a successful growth period. The light is obviously very important in as far as photosynthesis, but those hours of darkness are incredibly important as well, as during that time there’s an exchange of essential elements in your plants’ metabolisms.
This period will take more or less time depending on the seed, strain and growing method. Autoflowering plants will be much faster than feminized plants and indoor crops are generally much faster than outdoor crops. Also, if you use a stronger light your crops will generally grow faster than those with less powerful bulbs.
It’s difficult to put a number on how long the growth period takes due to environmental and external factors (fertilizers and the grower’s expertise) that can interfere with crops. Generally, indoors autoflowering plants take about 3 or 4 weeks (21 to 25 days) and around 6 to 8 weeks, maybe more, for feminized strains.
Outdoors regular and feminized seeds tend to take around 8 to 9 weeks, but by growing indoors you can mess around with the timings to make them begin flowering earlier.
This is your cannabis plants’ last period. When it starts will depend obviously on the growth period, but the plant must also have the necessary characteristics developed to allow it to grow buds.
This means that sometimes, a month after germination your plant might still look weak or small, which means that you’ll have to let it continue its growth period for more time.
It’s also important to note that autoflowering strains will flower at their own whim; you’ll need to change the light period once they start showing signs. However, seasonal seeds will need to be helped into the flowering phase by a change in light period. To be exact, you’ll need to switch them to a 12/12h light period which induces your plants into the flowering phase.
I know we said that the growth phase’s timing was relative, but true relative is how long a flowering period can take. There really are no rules apart from certain ones preached by seed banks about their strains, although in most cases these rules are simply guidelines.
The important thing to keep in mind when trying to figure out when the flowering period is coming to an end and you need to wash out the roots is how the buds look. Although times stated by seed banks can give you a general idea, the best way to find out is to watch your bud grow until they’re buried in pistils.
Once they’ve developed that fair, the harvest time will be indicated by the maturity and oxidization of the pistils and trichomes, which become that nice amber/honey color.
Indoors, autoflowering strains will generally finish up at around 8 weeks of flowering, and feminized versions can take longer depending on the growth period, and it’s normal for them to take anywhere between 10 to 12 weeks, and in a lot of cases even more.
Drying and Curing:
This stage isn’t even classifiable like the plant’s life cycle, although we can tell you that it’s a process that will take a while and it’s just an important as the plant’s periods when it comes to gett ing top quality taste, aroma, effect and potency.
First, you’ll have to differentiate between drying and curing; the first thing you’ll need to do with your freshly-cut harvest is dry it.
Basically, you’ll have to place your harvest, cut and trimmed, in a dark, cool and dry place in a drying mesh or sock (don’t forget to clean your plants roots out thoroughly towards harvesting time). All you’ll have to do is move the buds around the mesh or sock every day so they don’t become inclined to one side or another.
This process can take a while depending on placement and terrain; from two to four weeks. The sign of a properly dried bud is being able to bend it without breaking it, but while also hearing that nice crispy sound.
After the drying process comes the curing process, like a good cheese.
It simply involves placing all of your buds in a container and leaving it to sit with a periodic opening to let the air flow. Curing can be done in different containers; plastic, glass or wood, although wood is faster than glass and glass is the most recommended as it doesn’t emit or contain any sort of toxic substances.
The container in which you deposit your harvest will need to be kept in a dark, cool and dry place. The only thing you’ll need to do will be to open the container for about five minutes a day so that the humidity can leave your bud, and you end up with a perfectly chlorophyll-free product.
This process can take anywhere from two to six weeks. The main indication of a proper curing is that the bud crunches when pressed in slightly, if you bend the stem it breaks water than bends, and the intense green color should fade, as well as the leafy green smell.
According to these estimates, marijuana takes about three months to grow completely for autoflowering versions, and four to five or more months for feminized strains depending on crop method and expertise. Don’t forget that drying and curing will take a month or two more.
We’re going to insist on the fact that depending on how you grow your plants as well as the strain you choose to grow, each phase will be longer or shorter, and therefore so will the entire life cycle. Feminized strains will take longer to be harvestable, and autoflowering strains will take less time. There’s also a new version called the “fast version” that the Sweet Seeds seed bank has developed. Also, indoor crops will take less time to be harvestable than outdoor crops.
And don’t forget that patience is a virtue for every grower out there!
Author: Kiko Nieto, GB Collaborator
Translation: Ciara Murphy
Everyone's wondered how long marijuana plants take to grow at some time, and the answer is quite relative but we'll do our best to give you a general idea!