Marijuana Germination: 3 Basic Methods Compared

31 August 2020

Poor marijuana germination rates are the first issue that inexperienced growers face. Recently, a customer said he failed to germinate any of the seeds he had bought from me and complained. I decided to show him that my seeds were all viable and could be germinated successfully even with the crudest methods imaginable. Here’s how it went.

I took three caps from glass jars, three cotton disks, and 10 weed seeds.

marijuana seed germination temperature celsius 25C

Into one cap, I just poured a little tap water (of drinking quality) and dropped three of the seeds on the surface.

Then I soaked all the disks in the same tap water. I placed one disk into a cap without squeezing out the excess water and put three seeds on top. And then I squeezed the remaining two disks so that they were moist, but not wet through. I put the remaining four seeds there.

I placed all three caps on a window sill and covered them with a book because marijuana germination requires darkness. The temperature was about 77° Fahrenheit (25° Celcius). It’s well within the acceptable temperature range for marijuana.

weed seedling germination basic methods

After 64 hours, the results of my marijuana germination experiment were as follows:

On the surface of water – 2/3 germinated
On top of the soaked disk – 0/3 germinated
Between soaked but squeezed out disks – 4/4 germinated

Also, between the disks, the tap roots were the longest.

cannabis seeds germination rates experiment day 3

Interpreting the Results

What is the rationale behind this experiment? All too often, novice growers ‘drown’ their seeds in too much water. The thing is that embryos inside the seeds need oxygen to start growing. If you deprive them of oxygen, all processes stop. It happens when you put them too deep in the soil and water excessively. The same thing can happen when you don’t squeeze out the cotton disks.

So basically, pot seeds can be successfully germinated on the surface of water because below them there’s moisture and above them – oxygen, and there’s nothing to stop them from popping. I thought that by the same principle they would also easily germinate on the surface of a wet cotton disk, but the experiment has proven me wrong.

The method of germinating marijuana seeds between cotton disks demonstrated the best results in my experiment. No wonder this is the standard method for thousands of weed growers worldwide.

I also plan another experiment where I’ll be germinating one batch of seeds between squeezed out disks and the other one between disks that are dripping wet – just to show you how detrimental too much water is for the process of germination. Stay tuned.

Marijuana Germination in Soaked vs Moist Medium

Ha-ha! Great hypothesis! I’ve finished the experiment, and it was the exact opposite of what I had expected. As you can see on the photos below, the seeds that were germinating between wet-through disks have higher germination rates (5/5) and have on average longer tap roots (some of which are already covered by a lot of tiny ‘hairs’).

cannabis seeds germination between cotton disks or paper towels
On the left, you can see the seeds that I kept between cotton disks that were thoroughly squeezed out (they were pretty dry after 3 days). On the right, there are seeds germinating between very wet disks.

So I propose another hypothesis (hope it’s not as far off the mark as the previous one): excess moisture is okay provided that seeds have free access to breathable air. It’s what happens to plants in DWC where their roots float in water all the time, but get all the oxygen they need in the form of bubbles from air stones. So, if you use very wet cotton disks (or paper towels), don’t press them too tight against each other. Let there be a bit of space between them for embryos to breathe.