How Long Does It Take To Grow Marijuana?

by Liam | Last Updated: July 8, 2020

How long does it take to grow marijuana? With more and more states legalizing cannabis over the last few years, many people are starting to grow cannabis for the first time.

One of the top growing questions is “how long does it take to grow a cannabis plant” and have the end result of an incredible weed product?

The different stages? How many weeks in the veg stage? Or the flowering stage? Or how about auto-flowering cannabis plants? So many questions to comprehend!

How long does it take to grow marijuana

In this article we talk you through:

For a new grower, all this can be overwhelming. But it’s not as difficult as one would think.

All you need to do is break down the stages, keep a documented journal or calendar, and all the worries and concerns will drop away.

But to answer the question, “how long does it take to grow marijuana”, you can roughly estimate about three to five months from seed germination to the end of the curing a crop.

Keep in mind, the five months until the final step (curing) is complete is on the low side. The longer you let the cannabis buds cure, the more potent the THC levels can be. So, five months is a conservative time frame.

So for those people, or new growers, expecting instantaneous results, you need to sit back and let the “growing Gods” do their magic to produce the best possible harvest and crop.

Things To Consider

When buying or researching cannabis seeds to grow, always take the recommended stage time frame into consideration. Especially if you are growing different strains together. It may take some adjusting, but you can grow different strains with different time frames together. Keep track and recording all the data of a grow is paramount for a successful harvest.

How Long In Vegetative Stage

First you need to germinate the seed(s), which can take anywhere from one to seven days.

I have had seeds germinate in three days, while others take a second germination process; meaning it could take up to fourteen days to actually get the seed to start sprouting.

So be aware of this and have the time set aside to allow this late sprouting seed to “catch up” to the ones that germinate sooner.

You should always consider the seed producers’ vegetative recommendations; but those are not exact. It is more or less a guideline.

Depending on your growing conditions (i.e. Tent, lighting set up, temperature and humidity levels) it may take a week less, or longer than what is suggested.

As you grow more and more plants, or crops, you will get to know the plants and the conditions in which you are growing. 

If you are using clones to start a new crop, then you will by all means cut the vegetative stage down a few weeks.

Most clones are generally two to three weeks advanced in the vegetative stage; so many new growers may want to buy, or receive, clones.

So instead of having the vegetative stage being up to eight weeks (when sowing seeds), your crop will be about four to six weeks. 

During the vegetative stage, the plants are growing taller, developing branches and more leaves and the potential for more buds.

If you shorten this stage, your plants may tend to me shorter, smaller and may only produce a minimal amount of cannabis. Allowing the plant to grow to its full potential will take six to eight weeks. 

Sometime during this stage, if you started your seed(s) or clone(s) in a plastic cup, you will need to transplant to a larger container.

Once the plastic cup is full of roots (usually around two to three weeks), a five gallon, or larger, pot is needed to allow the roots to flourish and grow.

How Long In Flowering Stage

You can average the flowering stage to be anywhere from seven to nine weeks.

Again, you should use the recommendations of the seed producer, but also keep in mind your growing conditions play a key role.

While the strains’ genetics also are important, you  will know by the size and development of the bud when the plant is getting ready to harvest.

Having an LED Microscope that magnifies the trichromes is extremely helpful in determining the best time to harvest the cannabis.

Usually around week seven of this stage, you start inspecting the trichromes development and look for a combination of cloudy and clear in them.

If you harvest the buds too soon the THC levels will be low.

The best time to harvest is when the trichromes are at 70% cloudy. In the early development of the trichromes, they are clear.

But as the harvest continues, the trichromes will begin to fill up; displaying the cloudy appearance.

Auto-Flowering Strains

These strains are considered the easiest to grow; and may be the perfect ones for a beginner grower to start with. The upkeep is minimal.

Auto-flowering strains are geared to grow and develop within a specific time versus lighting requirements (24/7 hours with lights on during veg stage and 12 hours on/12 hours off during flowering stage).

Auto-flowers can be set to an 18 hour on/6 hour off light schedule from seed germination to the end of the flowering stage. No need for light timers. 

Another benefit is that auto-flower strains grow fast and can be ready to harvest in as little as 60 days (eight and a half weeks total).

There is also no need to transplant the auto-flower plants. They stay in the same container from seed to harvest; so make sure to have an adequately sized (5-10 gallon) pot to start the seeds in.

Please contact us if you have any questions. Thanks for reading!