Learn how marijuana seedlings develop by checking out the pictures of marijuana seedling growth day by day, With identification tips included 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. Jack Frost Landscapes & Garden Center blog for updates on sales and products as well as gardening tips and tricks, recipes, crafts, and more!
Marijuana Seedlings: Their Anatomy, Growth, and Identification
Your day-by-day and week-by week guide to marijuana seedling plants‘ progress from emergence to vegetative stage
In this post, we’ll talk about the normal growth of marijuana seedlings. It will give beginner growers a pretty good idea of what to expect day by day and help you keep your cool and not react with panic whenever you suspect trouble.
We understand that taking care of marijuana seedlings can be a nerve-racking experience. But it shouldn’t be. Just look at the pictures in this post and compare them with your little plants to see if they are doing okay. And if in doubt, consult our guide to seedling problems and how to solve them.
Table of Contents
Marijuana Seedlings from Day 1 and Onwards
So you’ve germinated your seeds between wet paper towels or using some other method and placed the sprout into a grow medium, like soil, or soil mix, or coco, or rockwool. We recommend covering the sprout by the medium completely, so that its tap root has something to push off from when it’s trying to dig deeper. And when the tap root has established itself in the medium, it pushes the seedling out of the medium and its ‘helmet head’ comes up.
If the medium is moist enough and coarse enough, the shell can peel off on its own. Otherwise, the seedling can be stuck in the shell and needs your help (see the link above to remedy this and any other problem). Below the shell, there is a thin film covering the cotyledons. Sometimes, it sticks and doesn’t let the cotyledons open, even after you have successfully removed the shell.
This is day 1 for three OG Kush Auto seedlings. Only one of them has cast off its shell on its own.
We have removed the shells from the seedlings on the right and in the center. The one in the center still retains the film though.
Sometimes, you will see the weed seedlings sprouting yellow. Don’t worry: it’s perfectly normal. The green color in plants is due to chlorophyll, a natural chemical that plants produce in the presence of light. And this process needs time. Give your yellow sprout a couple of hours under light, and it will start to turn green.
The First True Leaves
When the seedling sprouted, the pair of cotyledons will be ‘glued’ together – the way they used to be inside the seed, but soon they will move apart, and you will see the first tiny pair of true leaves tucked between them. Of course they will be whitish or yellow, too, at first.
On day 1, the cotyledons will be most probably pointing down, but on day 2 they will definitely straighten themselves (and so will the stem), and the first leaves with serrated edges will start to turn green and grow imperceptibly. These first leaves will have only one ‘finger’ each. The second pair – three fingers, the third – probably five.
Most of the Growth is in the Root Zone
The growth in the first week may seem painfully slow to you, but don’t you worry: the plants will pick up pace eventually, and right now a lot of progress is happening underground where the root system develops. The main root, called tap root, tries to reach as deep as it can.
That’s why it’s recommended to use deep pots or tall party cups for cannabis seedlings. But secondary roots also actively grow at this stage which will be evident to you if you use rockwool or jiffy pellets: the root tips will grow through their sides.
Control the Height of Your Marijuana Seedlings
Marijuana seedling height is controlled by the amount of light it receives. If everything is just right, the seedling is sturdy and not too tall: probably 2-3-4 inches the first several days, and hardly much taller when it is 1 week old or even 2 weeks old.
The seedling’s main business at this time is root development and the growth of leaves, not the overall height. If you see that each successive pair of leaves eventually grows bigger than the previous one, your young plants develop beautifully. At day 10, the span of the second pair should be the same as the span of the first one.
When Does the ‘Veg’ Begin?
It’s hard to point to the exact moment in time when a young plant stops being a seedling and begins its vegetative stage. You’ll see it happen when your cannabis starts to get noticeably bigger overnight. It may just grow higher, or rapidly develop side branches, or its leaves will get very large very fast. When you witness this sudden spurt in growth, congratulations: the vulnerable seedling stage is over and the plant has started vegging.
On day 1, one out of three OG Kush Auto seedlings has yet to ‘unglue’ its cotyledons.
This is Day 1 for Cream Caramel that managed to cast off the shell while emerging from the soil. It’s still yellow because it hasn’t yet been exposed to light.
Cream Caramel seedling at day 2. The cotyledons and the first pair of true leaves are already green. The stem is brownish-purple, but it’s perfectly normal.
OG Kush Auto at day 3. The seedling is in the process of straightening up.
This Six Shooter seedling is at day 4, and you can already see the second pair of true leaves.
OG Kush Auto at day 6. A bit stretchy and bent as a result, but oherwise healthy.
OG Kush Auto at day 8. Firts pair of leaves a bit wavy, probably due to overwatering at some point.
On Day 10 or so, the spans of the first and second pair of true leaves should be the same. This Six Shooter is actually 13 days old which means that its growth has been too slow.
A very sick seedling. Besides yellow, dry, and brittle leaves (due to too aggressive LED light), you may also notice that the second pair of true leaves, though developed, is much smaller than the first one. This assymetry is a clear sign of major trouble.
Green Crack by Fastbuds at day 11 develops nicely. However, there is evidence of mild heat stress.
This 2 week old Auto Euforia seedling has leaves with 1, 3, 5, and even 7 ‘fingers’.
With noticeable side shoots at every node, this young cannabis plant shouldn’t be called a seedling anymore. Now it’s entering the vegetative stage and will develop rapidly.
The Color of Healthy Marijuana Seedlings
Generally, your seedling’s leaves should be medium green, not too light and not too dark. If the green color is too deep, it can mean that there’s too much nitrogen (N) either in the medium (soil mix), or in the plant food that you’re feeding your cannabis.
If the green color is just a bit too dark or too light, maybe it’s the genetics (see below). And when the leaves are turning purple or you see purple veins, purple stem, or even red stem, it also can be attributed to genetics. However, sometimes the cooler temps, especially at night or during the lights-off period, may lead to reddish hues in stem or purple leaves. White stem (usually with some greenish stem color) doesn’t mean there are any troubles.
Yellow is the Color of Trouble
The yellow coloration is a different story. Most often, it’s a sign of trouble, so don’t be complacent and resolve the issue a.s.a.p.
The only exception is when you see yellow veins or yellow in the middle of leaves first thing in the morning. It’s because the growing parts of the seedling haven’t yet been exposed to light. Watch them for a couple of hours, and, most probably, these new leaf parts will produce enough chlorophyll to turn the healthy shade of green.
This picture was taken at lights on. The new tissue in the middle hasn’t received any light yet, that’s why it’s yellow.
Another case of normal yellowing is when cotyledons die off at some moment. They are necessary in the first few days of a seedling’s life, before true leaves develop. Then cotyledons become redundant, get yellow and dry. This is inevitable and happens sooner if the cotyledons are far from light or shaded by true leaves above them.
This plant is probably 3 or 4 weeks old. The cotyledons have already served their purpose, and now it’s time for them to die.
Marijuana Seedling Identification: How Much Can You Really Tell?
Some people are very impatient to identify their marijuana seedlings. Maybe, you’ve bought a mix of different seeds, and they are not marked in any way, so you can’t tell the difference between them. Or a friend has given you a bean or two, or you decided to try some bag seeds. So, what can a seedling tell you about your future rewards, if any?
Frankly, marijuana seedlings don’t reveal much. The only thing that you can tell with any confidence is whether your seedling is an Indica or a Sativa. Often, you can see the difference in the very first set of true leaves. Indica leaves have darker green color compared to sativa leaves that are more light. Indica leaves are also shorter, broader, and ‘rounder’.
Judging by broad, round leaves, this seedling has dominating Indica genes.
This Green Poison Early version has narrow, light green leaves that point to its Sativa heritage.
The Identification of Sex in Marijuana Seedlings
As for the seedling gender, you can’t tell male from female. Only when a young plant starts flowering, or, to put it more correctly, when it shows preflowers at the nodes, you can determine if they are female hairs or male fists.
This seldom happens earlier than at 3 weeks (in the quickest of automatic strains). For photoperiod varieties, you can only wait until the vegetative growth really kicks in and the first preflowers appear. Alternatively, you can speed up this process by switching your light schedule to 12/12, which can be done even from day one. However, it will be a significant stress for your seedlings if they start flowering like this and then you decide to revert them back to veg with 18 hours of light and 6 hours of darkness.
This plant has clearly shown its sex. It’s a boy. Note that you wouldn’t see male or female flowers in a seedling; only in mature plants.
A much younger cannabis plant has already shown male flowers.
Yet another plant (mature) showing male flowers at the nodes.
This young plant, probably 3 weeks old and not very healthy looking, shows the first white pistils (female hairs) on top. The yellow color in the middle probably means that the picture was taken at lights on.
Identifying a Keeper by Smell
There is one more thing that you can do to understand what you actually grow: you can slightly rub the leaves and smell them. The aroma should be rich and pleasant for you. That’s what breeders do who germinate hundreds of seeds and want to decide early on which ones to keep and which to discard. And, of course, you should look for marijuana seedlings that are healthy and vigorous, not sickly and small.
Not much of identification guide, we know, but it is what it is.
So now you know enough about marijuana seedlings to stop worrying and enjoy the process of growing. And if you want to make sure that your sprouts receive all the proper L&C, check out our article describing the ideal conditions for your weed seedlings and how to take good care of them.
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.
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.
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.
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.
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.
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
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.
Stages of Growing Cannabis
Cannabis, weed, marijuana, kush, ganja – whatever you want to call it, it’s now legal to own and grow in the state of Virginia. So what does this mean for those interested in growing it?
Growing Cannabis for the first time can be quite overwhelming. A quick Google search will lead you to hundreds of results with more information than you can ever sift through. There’s so much to learn – lighting, pH, soils, training methods, curing, and so much more. Where does one start?
It’s really easy to fall down the rabbit hole of information online. The sheer amount of information can almost hinder you when you’re first getting started. I think it’s easiest to just get started and learn as you go.
Starting with gaining a general understanding of the stages of growing Cannabis is a great place to begin before you try growing for the first time. It will help you have a decent idea of what to expect along the way.
How long does Cannabis take to grow?
How long Cannabis takes to grow can vary based on the variety of the plant and conditions it is grown in. On average, from seed to harvest, it takes anywhere from 10-32 weeks (about 3-8 months). It’s a quicker process if you start with a clone (rooted cutting) 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.
Stages of Growing Cannabis
Every plant begins with a seed. Cannabis seeds should be germinated just like any other seed. They can take anywhere between 3-10 days to germinate, although it can happen in as few as 24 hours or as long as 2 weeks. To germinate, you can place the seeds in a damp paper towel, which you should then place in a dark place, such as inside a drawer. Check on them after a few days to see if the primary root, called the radicle, has emerged. This will look like a little white “tail” coming out of the seed. Once germinated, move them to damp soil.
Alternatively, you can place the seeds directly in damp soil to germinate and grow, without having the trouble of moving them. For this method, I would recommend a seed starting mix. These are usually lighter and fluffier than traditional potting soil, which gives your fragile germinating seeds a start on the right foot. We carry Coast of Maine Sprout Island Blend Organic Seed Starter Mix. It has additional perlite that aerates the soil and helps prevent damping off. It also has mycorrhizae, worm castings, lobster meal, hen manure, and kelp to get your plants off to a healthy start.
2. Seedling Stage
Once your seed has germinated, it’s now time to move the germinated seed from its paper towel to a growing medium. If you started them in a seed starting mix, you will want to move them from the seed tray to a larger pot with a high-quality potting mix, such as the Coast of Maine Stonington Blend Grower’s Mix. This is a super soil, that works especially well for growing Cannabis. It contains mycorrhizae, kelp, alfalfa meal, fish bone meal, worm castings, perlite, manure, peat, coir, and lobster compost that feed your plant throughout the growing cycle, with no need to use additional nutrients.
Plants are considered seedlings for about 2-3 weeks after germination. During this time, the plant should be moved to a spot with direct sun, if growing outdoors. If growing indoors, set your grow lights to run for 16 hours a day.
3. Vegetative Stage
After the seedling stage, Cannabis plants move to a vegetative stage. This is the time when the plant focuses on leaf production. It will not produce flowers at all during this stage, as the plant needs to grow plenty of leaves to take up enough photons (sunlight) to create the necessary energy to produce large flowers. The vegetative stage can last anywhere from 3 to 16 weeks, depending on the variety.
During this stage, indoor plants need 16-18 hours of light per day, and outdoor plants need at least 6 hours of direct sunlight (“full sun”), plus several hours of indirect sunlight. They will also need plenty of Nitrogen during this point, as Nitrogen is the nutrient that promotes healthy leaf growth.
The flowering stage is the last stage of the Cannabis plant life cycle. This is the time when your plant will stop putting as much energy into leaf growth and will instead focus that energy on creating the flowers (buds), which are used for medicinal and recreational purposes.
Stages of Flowering – Source: Katie Plummer
Cannabis is triggered to flower when the hours of light it receives are reduced. 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 harvest. If you’re growing indoors, you get to play mother nature and can force your plant to flower at any point. When you’re ready for plants to start the flowering stage, change your lights to a 12/12 cycle ( 12 hours with the light on and 12 hours with it off ). You will see signs of flowering in 1-3 weeks . On average plants will be ready to harvest after 8-11 weeks of flowering.
Your plant will be ready to be harvested once flowers are compact and the pistils turn orange/brown. These pistils look like “hairs” coming out of the flowers.
To dry your Cannabis, hang sections of the plant upside down in a dark, cool space, such as a closet. You want to aim for 55-65% humidity and 60-70°F in the spot that you’re drying your plants in. Prolonged periods of light, friction from handling, and humidity/dampness can degrade resin glands, so you will want to avoid all of these.
During the drying process, plants lose roughly 75% of water weight, which increases the cannabinoid to weight ratio. It also helps equalize moisture content, preserve cannabinoids, and shed chlorophyll.
Cannabis is ready to trim once the stem snaps when bent, typically after 3-7 days of drying.
After your plant has dried, it’s time to trim! Trimming makes your fingers very sticky, so wear gloves if this is something you want to avoid. Simply trim off the larger leaves and stems. You can leave smaller sugar leaves if you’d like, as these still contain a good amount of cannabinoids and terpenes that provide the medicinal properties of Cannabis. It’s all personal preference of exactly how much you trim off. And you can save all the trimmings to make edibles, tinctures, salves, and more.
Curing is an essential part and the last stage in growing Cannabis. It helps the buds achieve full aroma. Curing is as simple as placing your freshly trimmed buds in a glass jar with a lid, like a mason jar. You’ll then want to place the jar in a cool, dark place, such as inside a drawer or in a cabinet.
During the first week of curing, you will want to “burp” your jars. This means you should open the containers once or twice a day for a couple minutes to allows moisture to escape and replenish the oxygen inside the container. After the first week, you only need to burp containers once every few days.
You should allow buds to cure for at least 2 weeks, but some people choose to cure for as long as 6 months. This helps stop the loss of moisture and to preserve flavors and aromas.