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cannabis seed growth stages

Stages of the Cannabis Plant Growth Cycle

Considering a career as a cannabis Master Grower? Or maybe just looking into growing some good old-fashioned self-supply? We get down to the ground and look at the stages of the cannabis plant growth cycle.

DISCLAIMER: Please make sure to check with your local state laws first before attempting any sort of backyard cannabis cultivation.

First things first: There’s a reason we call it “Mary Jane” and not “Mario John”. Cannabis plants are either male or female. This doesn’t usually matter to most plants because they tend to have both parts present, but in the case of marijuana: only the female plants pack enough CBD oil and THC for any sort of useful purpose. Male plants are only ever needed to produce seeds via natural means.

We say “natural means” because a regular cannabis seed has a 50% chance of growing into either male or female. Feminized seeds are 90% guaranteed to grow into a female plant and come from two female parents. Most seed banks sell this type so you can start there. But how can that happen? And what if you want to make more of them?

Well, like humans, females are genetically “XX”, while males are genetically “XY”. Treating a female plant with colloidal silver turns it into a hermaphrodite and forces it to grow male reproductive parts. It stays genetically female but will now be able to pollinate another female resulting to feminized seeds (as there is no “Y” chromosome to turn it male – mutations are known to happen, though, so it’s not a 100% chance of resulting to a female plant). We’re not going to go into the different types of seeds based on strain because that’s a long topic in itself. Anyway, now that we have the right seeds, it’s time to get on to the actual life cycle:

Germination Phase

Marijuana plants are notoriously fickle. An adequate amount of heat and water is required for it to sprout, otherwise, it just remains dormant. The quality of the seed plays a big part too. It should be hard, dry and look brownish in color. Green or off-white seeds are usually undeveloped and probably won’t germinate.

It is moisture that is the general trigger for germination, and most utilize the paper towel method for this which involves placing the seeds on top of two moist paper towels on a plate. Two other moist paper towels with a plate are placed above to function as a cover and stored at room temperature.

Germination takes around 24 hours to 5 days start and continues for 1-2 weeks. The start is signified by the emergence of a distinct taproot with small leaves that the plant will need to take in sunlight and grow.

Seedling Phase

Once the seed germinates and sprouts leaves, it is now considered a seedling. It is now also time to transfer it to the soil.

If you’re planting multiple seeds, take note that spacing will need to be considered. Allow at least 2-3 feet of space from one seed to the next.

This is the most sensitive point in the life cycle and usually lasts 2-3 weeks. Make sure that the environment is clean and that you’re not overwatering it (which could result in mold). A healthy seedling will have a vibrant green hue.

Vegetative Phase

The plant is considered as a seedling until its leaves form its distinct number of blades, after that and around its 3 rd to 8 th week of life, the cannabis plant enters its vegetative state where it will grow taller and wider depending on the strain.

It’s starting to look like a proper cannabis plant at this point, and its THC levels are starting to build up directly proportional to its daylight exposure – but don’t get all excited and pluck leaves out to use first, it is still very much a baby at this phase and any cannabinoid content in it will not be enough to be of any use.

Flowering Phase

Within its second to the third month of life, the cannabis plant will reach pre-flowering and flowering periods.

The pre-flowering period is important as it will show you early on if your plants turned out male or female. Male plants will have sack-like structures where the leaves and main stem is connected. You will need to weed these out as you see them as the pollen that is released when they mature and burst will decrease the potency of cannabinoids in the female plants. The distinct “hairs” that are generally associated with strong weed are a result of female plants that have escaped pollination (which is where the term sinsemilla comes from).

The Flowering Period is when cannabis arrives at its fully potent stage with the arrival of the long-awaited buds. The longer it stays in this period, the stronger the final product is. This is the final stage in growth and if you’ve made it this far, congratulations!

Harvesting and Pruning

…at least until you harvest, of course. While the plant is technically done growing and is usable once it flowers. How long it stays usable is another matter entirely.

The “hairs” on the pistil or the pistil itself is a strong indicator. The party’s over once they start curling up and turn brown because the cannabinoid content is starting to disintegrate at this point. The magic color to watch out for is reddish to yellow. Once it reaches this, it is at its maximum potency and needs to be harvested. If you’re in a pinch, harvesting early is better than harvesting late because it at least has some content during its early phases.

Pruning and drying is also a delicate process that takes as much time as actually growing. You’ll want to cut close to the stalk and gather your spoils. Hang them upside down to dry for around 4 days to a week and they’ll be ready to be separated. You can use the leaves and stems as general edibles and they’ll pack a punch if harvested at the right time, otherwise, you can choose to throw them away, it’s the buds that you want, after all. Once this is done, place the buds in a container, making sure they’re not too cramped, let stay for around 2-3 weeks. And now you’re done! From here, its just a matter of how you want to use it.


Most commonly, the terms “veg” and “flower” are used to represent the stages that a cannabis plant undergoes through its life-cycle, but there are nuanced differences in terminology that vary from grower to grower or product to product. To have more precise language and understanding, we’ve described each of these stages for both photo-period and auto flower plants, as well as identified small differences between stages for seeds and clones.

The Language We’ve Adopted for Growth Cycle Stages

At ETHOS, we recognize the following growth cycle stages of our plants:

Seedling (Rooting Stage)

Low Intensity uMole

Medium-High Intensity uMole

Maximum Intensity uMole

Clone (Rooting Stage)

Low Intensity uMole

Medium-High Intensity uMole

Maximum Intensity uMole

1st Trimester: Pistiling

2nd Trimester: Swelling

3rd Trimester: Ripening

The reason for the difference in clone and seed veg cycles is due to a seedling’s physical inability of flowering during the first 3-4 weeks of its life, while a clone can be flowered immediately. This changes environmental variables, specifically with seedlings’ tolerance and hunger for more intense lighting. Because clones are able to flower earlier, they can be susceptible to a pre-flower state if they are not receiving adequate uMole.

In the following tables, you’ll find more information about each growth stage. The stages are the same for seeds and clones, the plants just progress through them at different rates.

Photo-period Vegetative Growth Stages

A note on vegetative growth states for clones:

I like to follow a 7-10-10 regimen, that’s 7”, 10 days, 10 days. The first 7-10 days of a clone’s life it is primarily focused on rooting; you’re waiting for the rhizosphere to develop. For us, a plant 10-14 days after transplant will typically start to show significant growth. These plants are often between 6-8” tall. Once they have put out a strong set of fan leaves, we top and remove older/original growth. During the next few weeks, you’ll top the plants again (10 days after you topped them before), wait another 10 days (sometimes 15 for slower varieties) and flip the plant into flower. I find that any more than 5 weeks in veg leads to problems unless training for specific grow situations. Some of my best grows are done by doing only a 4-week veg before I flower; this creates much more efficient plants.

Photo-period Flower Growth Stages

A note on flower stages:

In indoor grows, flowering for a photo period plant begins when the light cycles are changed. In outdoor grows, the beginning of flower can typically be determined by the time when pre-flower/flower sets begin developing.

Grandpa’s Stash in pre-flower stage. Flower onset of Grandpa’s Stash R2: Day 10-12

Autoflower Growth Stages

A note on flushing and autoflowers:

About a week before ripening, typically you will start noticing significant nutrient deficiencies regardless of the feeding schedule. If you let the plant continue, the nutrient deficiencies will become more pronounced.

As with all timelines and growth stages, keep in mind that these guidelines are a good ballpark for typical plants. There are some plants that veg slower or faster than others depending on the genetics and variables in the growing environment such as lighting, VPD, and substrate used, which will all play a factor in this timeline. Remember that these guidelines are for typical commercial growing where adhering to plant numbers, not sea of green setups.