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how deep do i plant a marijuana seed

Maintaining the ideal temperature (between 22–25°C/71–77°F) and moisture for germination is tricky. Leaving seeds out in the open environment or on a windowsill is far from ideal; a DIY climate-controlled cupboard would do a much better service. A warming mat is perfect for maintaining a constant temperature, but it doesn’t tackle the issue of moisture.

There is, of course, a far simpler way to germinate seeds. Ideal for beginners, the feminized starter kit by Royal Queen Seeds has everything you need to kick-start your next cannabis project.

Place one sheet of damp kitchen towel on a flat surface. Space your seeds a few centimetres apart before placing the second piece of kitchen towel over the top. You need to ensure both pieces are damp, not wet. Once again, when the white root tips reach 2–3mm, move the seeds (carefully) to soil pots. Use the same guidance found above for planting techniques.


Timescales can vary, as it all depends on how ideal your germination environment is (see the golden rules above). Even the worst grower could make a seed germinate, but it may take a few weeks and, of course, increases the risk of a weaker plant.

Start by filling pots with a premium-quality soil that has been soaked in water. Many growers also choose to lace the water with a root stimulator. Make a hole roughly 10–15mm deep. This will be your seed’s new home. Remove the seeds from their packet and place them into the pre-dug holes. Loosely cover the seeds, but be careful not to compress the soil above the seed too much. The root will struggle to penetrate solid soil, slowing plant growth. Lightly spray the top of where you placed the seed so that your growing medium stays moist.

Two or three weeks after germination, your young seedlings should be ready for their new home. At this point you have two options; transplanting them into soil pots, or taking on the challenge of hydroponics. You’ll know when the seedlings are ready to be moved because the root system should start to poke out of the bottom of the wool blocks. As long as the roots haven’t begun to engulf the bottom half of the wool block, they will seek out water and nutrients in their new surroundings and continue to grow downwards.

Your growing pots will need to be placed in a damp climate that is within the temperature range listed under our golden rules. After 4–10 days, you should see a young seedling sprout, while the roots will have begun to develop underneath the soil. The entire plant and its soil can now be transferred to a larger pot, where normal growing routines should start.

Some growers use the damp paper towel method for the germination process. Sometimes, the newly-formed root of the seed can get stuck to the paper towel. The first instinct is to pull it loose carefully, but the action could potentially damage the plant. Instead, spray it with some water to encourage the root to let go of the paper towel.

It is important not to add extra nutrients to the soil to keep the plant healthy. The potting soil already comes with the necessary amount of minerals a cannabis seedling needs to grow. The young plant is vulnerable to a nutrient burn, which causes leaves to lose the meat it requires and turn brown or yellow

Step 4 — Cover the Seed With a Thin Layer of Soil

The positioning can help the top of the plant and its roots grow out correctly. The stem could bend and not develop properly, and the roots might sprout upward. The weed seedling might not turn into a healthy adult plant.

You have finished germinating your weed seeds, and it is now time to begin planting them. Planting weed seeds involves moving a seedling from a paper towel or small container to a larger pot. There are a few items you will need and tips to keep in mind.

The final step of the planting stage is one of the quickest ones to do. All you need to do is cover the cannabis seed with a thin layer of soil. About a couple of millimeters should do the trick. The thin layer is enough to block out the grow lights or sun while giving the seedling room to grow.

So, you should plant the seed with the tip down and the crown uppermost and facing you. Once the seed germinates the crown will serve as a hinge, so that the seed will open at the tip and let out the root. In case of placing the seed incorrectly, the tap root will grow upward and the seedling downwards, which should be avoided at all costs because it is likely that the seedling will not be born.

Sean 2021-05-17
I had my seeds in the paper towel for 3 days. The tap-roots appeared(not out just showing a bit) and I planted them in the soil. 3 days have past and I haven't seen any progress. Is there a reason why this is happening?

Tim 2021-05-13
Hi, thanks for your contribution. Mandala Seeds give some helpful advice but they don’t have a monopoly on germination methods! In my 20 years germinating seeds I’ve tried all different methods and I’ve found good and bad in all of them. except for the methods using moist paper towels, I refuse to use it these days – I found that’s a great way to get mold problems and a really bad start to the plant’s life! That definitely is far too much humidity. as for ambient humidity, we don’t specify anything in this post. What we do say is that the medium in which the seeds are germinating should be at about 70% humidity for the best results. There’s nothing wrong with using a humidity dome or mini greenhouse, as long as you know when to start ventilating. of course if it’s kept sealed all the time then problems are bound to arise! These days I start all mine in a glass of water with a few drops of H202 and then once the seeds open (usually 24 hours) they get transferred to the substrate. As for the point down/point up debate, I think I’ll need to do a side-by-side comparison to settle this in my own mind. I’ve always planted them point downwards or on their side and I’ve yet to see any weird stuff like roots popping out of the surface, or doing a loop-the-loop before the seedling breaks the surface. But it’s clear that the debate needs to be settled so I’ll do an experiment and I’ll be happy to be proved wrong! EDIT: I’ve since germinated over 100 seeds as a test, 1/3 of them went in the soil with the point downwards, 1/3 sideways, and 1/3 with the point upwards. Most of the seedlings broke the surface at around the same time but it’s clear to see that the ones that I’m still waiting for are mostly those that went in with the point upwards. The next step has to be a test in a terrarium so I can actually see what’s going on but I’m almost ready to call complete BS on this “point upwards” theory, FWIW. Thanks again for your comment, all the best!

Planting the seed incorrectly

In addition, the scarce space between the plants will also mean they will compete for available light, something not recommended if we want to get the most out of each plant. The plants will produce very little lateral branching, and will center their growth on a weak main stem, with too long an internodal distance, factors that usually affects negatively on the final yield of buds.

Too often the seed is buried too deep (a problem that we have already seen in case of watering after planting the seed), so the seedling may never emerge. In the other case, if we sow too close to the surface, we can find that the seed germinates well but the stem grows weak, bending and not allowing the seedling to develop correctly.

Although it may be tempting, germinating several seeds in the same container is not usually successful. In addition to the difficulty of correctly planting several seeds in the same pot, once they are born they will compete for the little space available for their roots. Having restricted root growth does not suit cannabis plants, which will grow more weakly and with greater internodal distance.

Tim 2021-05-17
Hi Sean, thanks for your comment. As long as the soil is neither too wet nor too dry, there shouldn’t be a problem with the seeds. They can take a few days to pop their heads up above the surface once they’re planted, the root needs to work its way downwards and find a solid hold to be able to push the seed head out of the soil. Speaking from personal experience, don’t be tempted to dig around looking for them as you’ll probably do more damage than good. The only times that seeds didn’t come up for me were the times I overwatered them, it’s crucial that they get enough air at this moment and too much water can lead to them rotting quickly. Of course, if they totally dry out then they’re not going to survive either. At this stage, I’d just recommend patience, good luck! Best wishes!