Now that you have some seeds, let’s take a look at what to do with them. There are 2 common ways to germinate cannabis seeds: outside of a grow medium (with a cup of water or a damp paper towel) and the old-fashioned way (just dropping a seed into a grow medium).
Germinating with a Cup of Water (Optional)
The cup of water method is exactly that: get a cup of water at room temperature, put the seeds into the water, and then keep them in there for up to 36 hours. This works because a high moisture environment is the trigger for a seed to start the germination process, and what better way to let the seed know that it’s ready to germinate than to dunk it with water? Just be sure to check on the seed every 12 hours to see if it has cracked open, and if so, it is ready to be planted. If by 36 hours, the seed has not opened yet, you will need to take the seed out of the water, as a seed can drown if it is soaked in water for too long. From here, you can either choose to plant the seed into a grow medium or proceed with the paper towel method by pouring everything into a paper towel on a plate and draining the excess water off the plate so that the seed can get some air.
Paper Towel Method
Germinating with a Paper Towel (Optional)
The paper towel method involves placing the seeds on top of a paper towel, covering them, and then wetting the towel so that it is damp but not soaked. Now, leave it in the dark at room temperature for a few days, checking on it every 12 hours, and moisten the paper towel if it starts to get dry. When the seeds have cracked open, they are ready to be planted. While most seeds will crack open in a few days, it could take up to a week for a seed to germinate.
With these two methods, the biggest benefit is being able to confirm early on that a seed is able to germinate. This way, you save time from having to wait longer to know if a seed is bad or not. Also, by immersing the seed in water to start, you guarantee the seed has the correct environment it needs to germinate. While this almost always happens when a seed is planted and then soaked with water in its grow medium (such as when planted in soil), sometimes the grow medium gets dry too fast, or the seed isn't enclosed enough by the damp grow medium for germination to trigger. So, by using a cup of water and/or a damp paper towel, you will guarantee the highest success rate for germination.
How to Plant a Cannabis Seed
You want the seed to be between 1/4 to 1/2 an inch inside the grow medium, just barely below the surface, so the plant will not have any trouble reaching the light but will be deep enough so the roots will not be exposed. If you are using an already germinated seed, try to plant it with the taproot facing down. However, after dropping it in, if it is facing up, don't worry about changing it as the plant will automatically know which way is down and the roots will turn accordingly as it grows.
Growing in Soil
The rule of thumb when starting a grow with soil is that the less soil you start with, the easier it is to manage. Here we will be covering how to start a grow with 3 different sized containers: a small peat pot, a 16 ounce plastic cup, and a standard full-sized pot.
Peat pots are pots made from peat moss, and they come in all shapes and sizes but are generally on the small side. These are commonly used because of how easy they are to work with since, while they are solid and able to hold soil, they are also fully biodegradable; the roots are able to grow through it, making it a breeze to transplant into a larger pot without having to remove the plant from a peat pot. This makes starting with a peat pot one of the best beginner options available. With less soil, the plant is much less likely to drown from over-watering; although, you will need to water more often.
Large disposable plastic drinking cups are also an extremely popular choice because of their wide availability and good balance between size and ease of use. With a plastic cup, you'll need to drill holes on the bottom of it to drain out excess water, fill it with soil, and then pop in the seed. Transplanting from a plastic cup to a larger pot takes a little more work because plastic cups are larger than most peat pots, but with the larger size, you can keep the seedling in a plastic cup much longer, all the way into the first weeks of the vegetative stage, before transplanting.
Finally we have an average-sized plant pot. Commonly made of plastic or clay, for cannabis pots made from breathable fabric are the recommended choice as they provide more air to the roots and prevent the roots from becoming root bound, which is when the roots reach the edge of a solid pot and then continue to grow in circles around the pot walls, which slowly suffocates the plant as the new roots slowly constrict the old roots. With a fabric pot, you just need to fill it with soil and pop in the seed, and while this is the laziest option, since no transplanting is needed as long as you start with a decent-sized pot. This is also the least forgiving option, as it is easy to accidentally drown the plant with too much water, so more care will need to be taken to ensure the soil is dry before watering again.
No matter what size you opt for, in terms of how much to water, there's no real water timeline guide. Based on the humidity, temperature, soil density, and the material of the pot, the water in the soil could evaporate in days or take a week to do so. The general rule of thumb is that if the top ½ inch of soil is dry to the touch, or for smaller pots when you pick up the pot and it feels like there is no water in it based on the weight, then it is time to water again with just plain water.
Growing with a Seed Starter Kit
Whether or not you decide to germinate a seed before planting it, the next step will always be to choose a place to plant the seed, and no other option is easier than starting with a seed starter kit. Seed starter kits are small self-contained small grow mediums specifically made to help germinate a seed, and they will hold the seed until it becomes a seedling, with the 3 most common options being rockwool cubes, rapid rooters, and peat pellets.
Rockwool cubes are a combination of rock and sand turned into lightweight fibers that work well in both soil and hydroponic setups because of its solid form that's able to provide a lot of air to the roots. They generally come out of the factory with a high pH so, to start, you will want to pre-soak them in a pH of 5.5 water for a few minutes to balance out the pH of the cube. From there, just pop a seed into the pre-made hole, and it’s good to go.
Rapid rooter plugs, and all the similar seed starter kits that look like it, are a mixture of organic materials bonded together into a sponge-like consistency. These are by far the easiest seed starter medium to work with. They are sold in moist packaging, so if the rapid rooter is already wet to the touch, you just need to drop a seed into the pre-made hole, and that’s it. If it has dried out, soak it with water, shake off the excess water, and drop in the seed.
Finally, there are peat pellets, which are pellets of dried sphagnum peat wrapped in a fine netting that allows roots to pass through them. To set one up, all you need to do is hydrate the pellets, watch them expand in the netting, poke a hole on top, and drop in a seed. These pellets are sold in multiple sizes, and for cannabis, we recommend getting at least the 42mm size or larger.
Since rockwool cubes and rapid rooters come in a solid form, both can be used for hydroponic and soil setups. Peat pellets, on the other hand, can only be used with soil, as the small bits of peat will float out of the netting when in contact with water. All seed starter kits also retain water very well, so you will want to water sparingly and only if the seed starter kit feels dry to the touch.
Jiffy Peat Pellet
When to Start Adding Fertilizers
Cannabis seeds are able to support themselves with just plain water until after the first round leaves have appeared, so we recommend using no fertilizers until after that point. There are some fertilizers that specialize in helping with germination and early root development, and if you want you can use these early on but the plant should be just fine on its own without it. Once the first true leaves have started to develop if you are not working fertilized soil you can slowly start including a grow fertilizer at a slow pace, utilizing only 25% of the recommended amount until the plant is in the vegetative stage.
Transplanting to a Larger Pot
After germinating a seed, no matter what you used as the grow medium, unless you started the grow with a medium- to large- sized pot you will need to eventually transplant the seedling to a larger pot. The best time to do so is when the roots begin to outgrow the grow medium that it is in. This is easy to tell with any of the starter grow kits, as well as with peat pots, since the roots will start to appear outside the grow medium, but if you are using a small plastic cup/pot, the easiest way to know when to transplant is when the fan leaves start to grow larger than the cup/pot size.
When transplanting, if you are using a seed starter kit or a peat pot, just dig a hole in the soil and drop it in. Also, with seed starter kits, be sure that the hole is deep enough so the soil completely covers the seed starter kit. This is because all seed starter kits are made from a variety of materials that will absorb water and dry at a different speed when compared to soil especially if exposed to air; the most effective way to mitigate this is to bury it. If you are using a plastic cup/pot, then wait until the soil is dry first so it does not cling onto the walls of the cup/pot. Give it a good shake to loosen it up, turn it upside down while keeping the main stem between your thumb and index finger so that it does not fall to the ground, and let it slip out into your hands. From there, just dig a hole into the soil of the larger pot and put it in. After transplanting, be sure to completely wet the pot with water; this will help the transplanted roots and grow medium integrate with the new soil around it.
Finally, if your cannabis plant seedling is long and stringy due to low lighting conditions or excessive heat, which causes it to stretch, then be sure to plant most of the long stem under the soil. This will help stabilize the plant and have the added benefit of slightly lowering the overall height of the plant.
What Method Do We Recommend to Start a Grow?
While the cup of water and paper towel methods both provide peace of mind by confirming that a seed has germinated as early as possible, my favorite method of starting a grow is by dropping a seed into any seed starter kit, as all of them take up very little space, are easy to work with and can confirm that a seed has germinated almost as fast as the cup of water / paper towel method without all the extra work.
Did this guide help? This article was taken directly from The Absolute Beginner's Guide to Growing Cannabis book, so if you like the advice above you'll love the rest of the book, which includes a lot of exclusive content not found anywhere else. You can find both the e-book and paperback copy on Amazon, and it's free with a Kindle Unlimited subscription!