Growers of all skill levels germinate cannabis seeds in paper towels. It is beginner-friendly and commonly used to test the germination rates of seeds.
Germinating marijuana seeds step-by-step using a paper towel:
Why germinate cannabis seeds in paper towels?
Germinating seeds on or in damp paper is popular among cannabis growers because it lets you see that your seeds have successfully germinated before planting them.
Using paper towels to start seeds offers a “happy medium” between germinating in water and sowing directly in their intended growing substrate. It lets you watch them for progress but affords slightly more flexibility in your timeline by preventing the sprouts from drowning if you cannot check on them and plant them as soon as they are ready.
How to Germinate Cannabis Seeds – Paper Towel Method
Time: 12-48 hours
Difficulty: Beginner-friendly
Step 1
Assemble the following
Clean water (distilled water is best)
Clean glass or cup (for optional pre-soaking step)
New zipper-top style plastic bag or other very clean moisture-preserving container (like a plastic Tupperware container or two plates placed face-to-face).
Paper towels or coffee filters (unbleached paper is best)
Splash-proof label and pen.
Step 2 (Optional) Pre-soak your seeds
In nature, seeds absorb water from their environment to start germinating. Growth can be slowed or stunted if there is not enough available moisture for each stage of development. Pre-soaking can help germinate seeds. By pre-soaking your cannabis seeds before placing them in paper towels, you make sure the seeds do not have to absorb all of their water from the paper itself.
To pre-soak your marijuana seeds, put about ½ cup of clean water in a container. Drop each seed into it, and if any resist sinking, use a very clean finger or other sterile tool to poke it and encourage it to be wet on all sides.
Give marijuana seeds 4-8 hours of pre-soaking time before moving on to Step 3.
[On the chance that this is all the time and effort it took for your seeds to germinate, wow! You can move on to transferring your sprouts to their future growing medium].
Step 3
In a clean environment and on a sanitary, flat surface, lay out a single sheet of clean paper towel. Dampen the paper towel to the point of being very wet but with no pooling water.
Step 4
Place your cannabis seeds in a row on the wet paper towel 1 inch (about 2cm) apart from one another and at least 2 inches (4cm) from the edges of the paper.
Step 5
Cover the seeds with another sheet of paper towel. Moisten the top sheet of paper and softly pat or press the top sheet to ensure good, even contact between the seeds and the paper.
Step 6
Gently roll or fold the two pieces of paper into a loose tube to hold the marijuana seeds in place. Place this tube into your plastic bag or other container and close it most of the way. If you live in a very arid environment, where paper exposed to air is likely to dry out quickly, close it all the way.
Step 7
Label your germination batch. Note the Date, Time, Number, Name, and Type (e.g. feminized, autoflowering) of germinated seeds.
Step 8
Place the contained seeds and paper in a safe place. This should be draft-free, out of direct light, and within a comfortable temperature range of 70-85°F (20-30°C). People often find a warm spot, like on top of a refrigerator works well.
Step 9
Set a timer to remind yourself, and check on the weed seeds after 12 hours by carefully opening the container and unrolling the paper. Avoid touching the individual weed seeds and disturb them as little as possible.
If your seeds have “tailed” (the small rootlet or “radicle” has emerged from inside the shell), rejoice! Go ahead and plant them.
If you don’t see any signs of action, check how dry the paper towels have become, and re-moisten if necessary using a mister. Re-roll the tube and put the whole set-up back in its germination-friendly environment.
Step 10
Use step 9 to inform your decision as to how soon to check on your cannabis seeds again. Give them another 12 to 24 hours to pop. If you’re still not seeing any progress at that time, consider trying a stratification or scarification technique to help stubborn seeds germinate.
Dos and Don’ts for Germinating Cannabis Seeds in Paper Towels
Do:
Work as cleanly as possible. Wear gloves, thoroughly wash your hands, or use hand sanitizer before handling your seeds and anything they touch.
Use a brand-new plastic bag or a very clean container.
Use unbleached paper when possible. It is generally firmer, providing more stability to your seeds and exposing your new sprouts to fewer residual chemicals that may negatively affect their growth.
Keep seeds of different types separate. If you’re starting more than one cannabis varietal at the same time, use a unique container for each one.
Don’t:
Let the paper towel dry out. This is one of the most likely causes for cannabis seeds to stop growing once they’ve started germinating.
Drown or suffocate your seeds. Standing or pooling water is a sure sign of too much moisture, and you should allow some evaporation and air exchange to occur by leaving a slight opening in the container.
“Cook” your seeds. Although the ideal range for germination falls within a typical household’s “comfortable” temperature, enthusiastic new gardeners sometimes think “warmer must be better.” Using a heating mat or pad can easily make it too hot for your seeds to breathe properly and dry out the paper.
Be rough on your seeds. Brand-new rootlets are very delicate and sensitive to friction. Sometimes, vigorous seeds germinate so quickly that they try to grow through the layers of paper between checks. If this happens, it is better to re-moisten and gently move the paper away from young seedlings rather than pull them from the paper.
Want to make sure there are no mistakes when germinating marijuana seeds using the wet paper towel method? For all tips and tricks, download Bergman’s Grow Bible below.
What to do if seeds seem “stuck” in their shells
Cannabis seed shells are designed to come off by pushing up through soil toward the light. Some cannabis seeds are so primed to grow that they propel themselves out of the shell even without help from the dirt.
If the seed leaves (cotyledons) are visible, but their tips are stuck together inside the still-attached protective structure, you may need to very carefully (emphasis on very) use sterile tweezers to pry the casing open to release them. They should be able to open up like a book after that.
In general, you won’t need to resort to this kind of intervention unless the sprout has already straightened out completely and is more than an inch (2cm) long before you transplant it.
Final Thoughts
Your seeds are counting on you to provide the cues that they have found a safe and supportive place to grow. Consistency and care are key to finding the best germination method for you and your gardening situation.
With the paper towel method, you can see how a young cannabis plant starts its life. As you observe the process, remember that nature has developed all of the structures inside each seed for maximum survival of the species. Isn’t it incredible that all the cannabis you’ve ever encountered, at some point, was nothing more than such a tiny little sprout?
Until next time, may you and your garden keep growing together, higher and higher!
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