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.
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.
Marijuana light cycle: 12 hours a day
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.
Marijuana light cycle: 16 hours a day
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.
Vegetative stage length: 3-16 weeks
When should you grow marijuana?
Seedling stage length: 2-3 weeks
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.
How to Grow a Pound of Cannabis – Step-by-Step Instructions from Seed to Harvest
If you choose the right strain, you could be smoking your own buds as soon as 3 months from germination!
These cannabis plants were vegetated for about 9 weeks before being flipped, in the exact same setup as above, and produced over 10 ounces each. Besides an extra week of veg, the biggest difference between this grow and the one above was simply the strains.
Check out examples of new grower shopping lists to learn exactly which supplies you’ll need.
Time Needed to Grow Weed, From Seedling to Harvest
I personally recommend at least 4 weeks in the vegetative stage with 18+ hours of light each day for the best results. Plants that are forced to start flowering sooner than 4 weeks don’t yield much compared to how much work you put in. That being said, keeping plants relatively small does have some benefits!
Medium (8-12 weeks)
Your plant will likely double in size (maybe a bit less, maybe more) from when you first put it into the flowering stage; this is known as the Flowering Stretch. So make sure you end the vegetative stage before your plant reaches half the final height you want, or your cannabis plants may outgrow your grow space during the flowering stage!
Before You Start Growing Weed
Ultimately, How Long to Harvest Marijuana Depends on the Desired Yields, Strain and Grow Style
To give you an idea as to what your FINAL marijuana plant may look like depending on how long it spends in the vegetative stage…
You want to get an auto-flowering strain. These cannabis plants automatically start making buds after about a month from germination, and are ready to harvest by the time they’re 2 or 3 months old.
Depending on how you set up your grow, it can take anywhere from 2 months to 6 months or more to grow a marijuana plant from a seedling to the point where the plant is ready to harvest. Some methods, such as growing hydroponically indoors, give your flexibility to get a harvested plant in as little as 2-3 months. Growing outdoors generally takes longer than growing indoors and is more dependent on when you plant your seeds and how long your growing season is.
Zkittlez Auto is ready to harvest 8-10 weeks from germination. Every time I grow this strain the smell and bud effects are excellent
Many other breeders also produce great auto-flowering strains (Dutch Passion, FastBuds, Barney’s Farm, etc.), but the following breeders stand out for consistency.
This gives you the freedom to choose the exact strain you want without any worry about how long it will take. This gives you the freedom to grow some strains that otherwise are inaccessible to growers who are worried about timeframes.