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 8 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 Does it Take to Grow Cannabis Plants?
Thursday September 5, 2019
T here are many reasons to give growing your own cannabis a try. Regardless of whether you’d like to grow the herb for either medicinal or recreational purposes, tending to your own cannabis plants can be done for many purposes and may even be more affordable in the long run than purchasing marijuana at your local dispensary.
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, what it really needs is time and attention.
The Time it Takes to Grow Cannabis
Grow times for cannabis plants vary widely, but on average, are 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, whether indoor, outdoor, greenhouse, hydroponic, coco, etc. 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 Indica 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 is that they tend to be more short and bushy than sativas, making them a better fit for indoor setups or growing in a backyard garden.
Cultivation Time for Sativa Cannabis Plants
This cerebral and uplifting cannabis variety poses more challenges than growing indica. In addition to their longer ten-to-twelve week flowering period, sativas 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.
Cultivation Time for Hybrid Cannabis Plants
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. But, 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. Since hybrids 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.
If you do decide to grow your own cannabis, plan on approximately seven months from when you plant to when you can consume your homegrown stash.
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.
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.