How to Plant Cannabis Seeds Indoors
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Growing cannabis at home can be a fun project and a nice way to have your own cannabis plants on hand. You may want to grow cannabis indoors due to inclement weather in your area or due to a lack of green space in your yard. Start by germinating the seeds. Then, plant the seeds in soil or in a starter cube. Once the seeds have been planted, care for them properly so they grow and thrive.
- After 12 hours, place the viable seeds on a towel.
Wet one paper towel and put it on a plate. Paper towels are thick enough to retain the moisture needed to help the seeds germinate. Place one paper towel under running water until it is wet to the touch, but not dripping wet. Use a ceramic dish or plate, as it will be strong enough to hold the towels and the seeds. The paper towel should cover the dish or plate.  X Research source
- If you do not have enough space on one plate for all your seeds, soak two more paper towels and put the remainder on a new plate covered in a wet paper towel.
Wet other paper towel and place it over the seeds. Make sure the wet towel makes contact with the seeds.  X Research source
- You can try using a heat lamp near the seeds to keep them warm. Do not warm the seeds up too much, as you do not want your heat source to dry out the paper towels.
- If the seeds become too dry, they could die and never germinate.
- Be very careful with the seeds as they open. Avoid prodding, pulling, or touching the seeds, as you do not want to damage the roots.
- Any seeds that have not opened and grown roots within a few days should be discarded, as they are not viable.
- As an alternative to soil, you can use starter cubes from your local nursery or online. Starter cubes are pre-cut growing pods made of composted bark. They contain a hole where you can place the cannabis seeds and grow them in good conditions. Basic starter cubes are inexpensive and easy to use.  X Research source
- If you make planting holes that are too shallow, the seed’s roots will not have enough soil to grow well. If you make the planting holes too deep, the seed will have a difficult time sprouting.
- Do not pull or tug at the seeds when you pick them up with tweezers. If they are stuck to the paper towel, wet the towel with water to make the seeds easier to pick up.
- Do not press hard on the seeds when you cover them, as this can disturb their growth.
- If you are using starter cubes, pinch the top of the holes in the cubes closed.
- Maintain a growing temperature of 75 to 85 °F (24 to 29 °C) for the plants so they thrive.
- Stick to a regular watering schedule so the plants get enough moisture. You can plan to spray the plants in the morning and then again at night so they get the water they need.
- Grow lights range from $200 to $1,200 USD depending on the size and model.
- You can get cool white grow lights at your local hardware store or online.
Avoid touching or handling the seeds as they grow. Touching or handling the seeds can damage them and stunt their growth. With the right growing conditions and care, your seeds should sprout and poke out of the soil within five to ten days.  X Research source
More than 12 hours of light a day for about 4-6 weeks as the plant matures will be enough. Once the plant is a decent size, you may induce flowering. Switch the plant to a timer of EXACTLY 12 hours of strong light (the more sunlight the plant gets, the more energy it can devote to flowering).
Yes, it is bad for the plant to have water constantly sitting at the bottom of the pot. It could make the roots rot over time.
You can actually find LED lamps made for growing plants online. If you don’t want to bother with that, you can just get a purple light to grow them under. There are many articles online talking about the effects of colored lights on plants.
If you plan on growing short, fat plants, they should be at least 6′ apart. You don’t want the plants rubbing on each other or shading the other plants. You will also want to select a spot to ensure all plants will receive maximum sunlight.
You can start as soon as you see two little leaves budding. During that time, make sure to use distilled water when watering them.
Cannabis thrives in a comfortable room temperature when grown indoors, or a little warmer – not too dry, not too humid. If it feels too hot or too cold for you, it’s probably too hot or too cold for your cannabis plants.
You can’t. You can try keeping it by a window, but you still won’t have much success. Lights aren’t that expensive, look on Amazon.
Yes, rain water is fine for any plant. The use of distilled water is to keep from adding tap water contaminants.
Keeping the plant from “stretching” is simple. Place the lights closer to the top of the plants. There are good video examples on YouTube showing two seeds started at the same time and placed under lights at different heights. The plant with inadequate lighting actually “reaches” for the light, growing tall and thin with longer internodal gaps. The seedling with closer light grows short and squat, with less stem between leaves (internodal distance), which means a better frame and plant structure for supporting the massive buds that you want to grow. As the plant grows, raise the lights with it. (Most folks suggest somewhere in the 16-30 inch range from source to canopy.)
The cultivation of cannabis is considered illegal in many jurisdictions. Make sure it is legal to grow cannabis in your area.
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This article was co-authored by wikiHow Staff. Our trained team of editors and researchers validate articles for accuracy and comprehensiveness. wikiHow’s Content Management Team carefully monitors the work from our editorial staff to ensure that each article is backed by trusted research and meets our high quality standards. This article has been viewed 1,322,363 times.
To plant cannabis seeds indoors, first soak the seeds in lukewarm tap water for 12 hours. Discard any seeds that float to the top. Then, place the seeds on a damp paper towel on a plate with 1 inch (2.5 cm) of space between each seed. Cover the seeds with another damp paper towel. Keep the seeds in a spot that remains between 70-80°F (21-27°C), and spray the paper towels with water whenever they start to dry out. The seeds will sprout in 2-3 days. When they do, fill pots or a growing tray 3/4 of the way with loose potting soil that has a pH between 5.8 and 6.3. Press the soil down lightly, leaving some air in it. Then, use a pencil to poke 1 inch (2.5 cm) holes in the soil. Place the sprouted seeds vertically in the holes and fill the holes with potting soil. Water the soil thoroughly and place the pots or tray in a spot that’s always 75°F (24°C) or warmer. Set up a grow light over the seeds and leave it on at all times. Water the seeds every day so the soil doesn’t dry out. The seedlings will emerge in 2-4 weeks. To learn how to use cool white grow lights to help your cannabis seeds grow, keep reading!
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Do I Have To Germinate My Marijuana Seeds Before Planting?
I heard that if I don’t, then it would take longer for it to grow? Is this true? What will happen if I just plant it without doing this?
No. it is better to plant them straight into soil. too much can go wrong between germination and planting..but if you do it all at once then you can’t have any of those issues.
Some people use a wet paper towel, and I can say I have done this myself more than a few times. but there are too many times that I let the paper towel get too dry, or it gets too hot, Or the seed sprouts and I rip it to pieces before I can get it in the ground. or when you go to pull it off the paper towel it rips the teeny tiny new little root. The only issue with planting the seed straight away is that you can’t check to see what is going on. but after a few days you should see a sprout. if after 4 days I don’t have a sprout, I gently try to dig around the baby plant and see what is going on. The only issues with soil planting is that sometimes you might plant the seed too deep, in which case you will know if after 4 days you have no sprout, because when you go looking for it. you might find a tiny sick looking little seedling just stuck under the soil, in which case you just move it up a little, no harm as long as you catch it before it is too late. or you plant the seed too shallow and it sprouts out of the ground with it’s seed shell still stuck on. which is really easy to fix as well. just wet it really well adn then gently remove the stuck shell, or just leave it alone. I am a shell picker though. also if the seed shell is still on you can bury it a little more. the seed shell gets soft when it is wet and then the plant can just split it open and go on. but if the seed shell is above ground it dries out and gets hard like the original seed, and sometime the plant can’t make it out..but as long as you keep the seed shell wet it will get pushed off naturally by the plant.
It will take longer to sprout is what you mean, not exactly longer to grow. Planting right into soil would be like how nature intended. Add a little heat plus keep it moist and it will be the same as if it were growing in the ground outside almost.
Germinating before hand will just eliminate your chance of a dead seed not growing. Plus you risk contaminating your seed if you handle the seed and touch its roots when its thats small. I personally have not seen that case but it was something to keep in mind. Always wash your hands before and after you handle.
I let them soak for an hour in a lite hydrogen peroxide solution then straight to planting in my medium of choice.
It’s your choice you can germ them in a paper towel or just chuck them straight in some peeps pre soak them some don’t it’s all a learning curve
I pitch mine into a shot glass of water for 12-24 hours & then straight into the dirt.
Works like a charm.
Place seeds in a glass of water for 24 hours then place them in paper towel soak paper towel with water but not to much place paper towle on a teaplate put a bow over then place in a warm area.
Leave for about 6 hours check it has not dryed out wet agian if needed leave for 6 hours repeat until you see the tap root let that get to about 2.5cm long then plant into the soil root pointing down.
Interesting. I just noticed that one of my darker seed has a little “white root” coming out of it. Its really small but I think I will plant it. I just want a small plant with bud on it.
i use the paper towel method
2 small matching plates, fold a paper towel in 1/2 twice (2 folds) dampen paper towel (to make it easier to work with) put seeds in middle and then soak the paper towel, place second plate on top put in a warm spot and within 48 hours you should have some tap roots coming out. i have had a couple seeds take longer than 48 hours but the average is about 24-36 hours. i generally let them sit in the paper towel for ran additional 24 hours after i first see a root, then just take a pen, poke a small hole in the medium and place the seed in the hole and moisten the soil.
the biggest thing is to “moisten” the soail not saturate it, and after you moisten it you shouldnt have to add any water for a while (unless you have some really hot/dry conditions that small seedling will never use all that water) at least 2-4 days you want the soil to dry out a bit so the root has to “search” for water towards the bottom of the container
biggest thing that kills small sprouts/seedlings is death by drowning, either you cause a situation called “damping off” or you just straight up drown them either way dont over water them, they only need the bottom 1/2 of the soil to be moist so its ok if the top layer gets a bit dried out.
good luck, plant more than one if your using reg seeds (i suggest at least 4) so your not setting yourself up to get let down after 4-5 weeks of growing a plant to find out its a male. if your inside get some decent lights, CFL’s are a bit “cheaper” (not really but you can buy a couple at a time so the up front cost is spread out) than a HID light. inadaquet lighting will also set you up for a let down as you will grow a plant for 12 weeks (minimum maybe more) just to get a gram of 1/2 way smokeable herbs
lots of good info and people on this site to use to your advantage just try not to keep asking the same questions a million other people have already asked like “how do i germinate a seed” do a bit of research and when searching go right to the advanced search instead of using the quick search as it yeilds better results.