The complete guide to germinating cannabis seeds
Before you can be met with bountiful hauls of dank buds, there are several stages of cannabis growing that take precedence. Unless you can successfully germinate cannabis seeds, you won’t have a plant to harvest. Give your seeds the best possible start in life by reading our definitive guide to germination.
THE ART OF GERMINATING CANNABIS SEEDS
Often overlooked, it is all too easy to assume that the vegetative and flowering stages of cannabis growth are the most critical parts of the plant’s life cycle. However, with the chance of failure high unless you know what you’re doing, poor planning when it comes to germination can make or break your next grow. Giving your cannabis seeds the best possible start on their journey to bulging buds is a surefire way to encourage a healthy and robust plant.
Small, fragile, and in desperate need of a helping hand, there are several ways you can germinate your cannabis seeds. All methods have varying degrees of success, with both advantages and disadvantages. It is important to note that even with advanced growing expertise and top-of-the-line equipment, you may still end up with a few failed seeds. This is a natural part of dealing with a living organism. At Royal Queen seeds, we only sell feminized cannabis seeds, so there is no need to worry about removing male plants.
WHAT TO LOOK OUT FOR IN CANNABIS SEEDS
Regardless of where you get your seeds from, it is best to give them a slight (and delicate) inspection before planting. Most of the time, all seeds will germinate; however, poor-quality seeds will produce a weaker plant. Unfortunately, that is something you will not find out until well into the vegetative and flowering stages.
To avoid disappointment, seeds that have a darker colouration stand a better chance of germinating, while pale green or white seeds are likely to fail. Even if dark seeds look slightly damaged, they should be planted anyway. There is a good chance they will still germinate, even if the outer shell is somewhat crushed.
GERMINATION TEMPERATURE PLAYS A CRUCIAL ROLE
Before we jump straight into the germination methods, there are a couple of germination golden rules. For the best results, we recommend staying within these guidelines, no matter how you choose to germinate. That being said, of all the factors to consider, temperature is one of the most critical. Seeds will always seek out even the smallest amount of moisture, but they use temperature as a sign that they need to do so.
• The ideal temperature is between 22° and 25°C (71–77°F)
• Your growing environment should be damp/moist, but never wet
• Relative humidity range should be between 70% and 90%
• Seeds favour fluorescent lighting (Cool White code 33)
• Minimise the amount of seed handling you do
• In hydroponic/rockwool plugs, the ideal PH value is 5.8–6.2
WHAT IS AN EXPECTED GERMINATION TIME?
Three fundamental principles will trigger that first small taproot to appear: warmth, moisture, and darkness. With the promise of moisture, a single root will take shape before slowly developing into the cannabis plant we know and love. In the right conditions, seeds will begin to develop within 12–36 hours of moisture being introduced to them.
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.
CHOOSING YOUR GERMINATION METHOD
GLASS OF WATER APPROACH
Arguably one of the least effective methods, but it is still viable. Incredibly simple to facilitate, beginner growers may opt to germinate their seeds in a glass of water. Half-fill a glass or bowl with water that is approximately 22°C (71°F).
After 3–5 days, the seeds will start to open, and you should see tiny white tips appear. Once these roots reach 2–3mm in length, use extreme care to transfer them from the water to pre-prepared soil pots.
The soil pots will need small holes (roughly 10–15mm deep) for the newly germinated seeds to be placed into. Once the seeds are secure, you will want to place a fluorescent light 13–15cm (5–6 inches) away to encourage growth. Finally, don’t risk overwatering your seeds at this early stage. Use a plant mister to make sure they stay damp but not soaking wet.
WET KITCHEN TOWEL METHOD
Probably one of the most common methods of germination. The kitchen towel method comes in several iterations. Some growers use cotton wool pads or absorbent pieces of paper. For this guide, we will be using kitchen towel as it is readily available and holds moisture relatively well.
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.
PLANTING DIRECTLY INTO SOIL
Planting directly into your growing medium prevents having to move seeds when they are at their most fragile. That first root tip is covered with microscopic filaments that are easily damaged. Given that both a cup full of water and moist paper towels are more prone to temperature fluctuations from their environment, planting in soil is a much safer option.
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.
If you don’t like the idea of pre-soaking your soil, you can use a spray to moisten the holes before you plant each seed. With enough moisture surrounding your seeds, you can still encourage a root to develop.
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.
USING STONE WOOL BLOCKS
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.
You will need to invest in a few pieces of unique equipment, but by using stone wool blocks, you can create a perfect utopia for germinating cannabis seeds. Soak the stone wool blocks in the same way you would a soil medium. The wool will retain the moisture and prevent the need to water during the early stages of germination. After the wool blocks are soaked, stick them in a plastic tray that also has a lid. Large cake tubs are ideal.
The dome of the plastic container will create your seeds’ own mini tropical climate. If you then place all the components in a temperature-controlled cupboard, you will have created a self-perpetuating supply of moisture—no need to touch the seeds again until they are ready to be transferred to your final growing medium as a young seedling. Using the stone wool block method, your seeds should germinate in one to two days.
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.
ROYAL QUEEN SEEDS FEMINIZED STARTER KIT
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.
The Royal Queen Seeds Feminized Starter Kit contains:
- 3x RQS Critical feminized seeds
- 20x Easy-Start seedling pots
- 1x Propagator Pro
- 1x pack of Bacto
- 1x perlite
- 1x fluorescent lights
- 1x instruction manual
- 4x AA batteries
- 1x Royal Queen Seeds catalogue
*You will also need a measuring cup and a stirrer (not included in the kit).
1. Gently remove the foil from the back of the seed packet and place them carefully into a dry container.
2. You will need a shallow container that is large enough to accommodate the seed tray. Fill the container with one litre of lukewarm water (22–25°C/71–77°F). Pour in the packet of Bacto enzyme, allowing it to dissolve before setting the seed tray into the container to soak. The seed tray only needs to be immersed for 5–10 seconds. Do not discard the Bacto mixture after the seed tray has been soaked.
3. After removing the seed tray from your shallow container, poke a 10–15mm deep hole into the soil of each pot, and delicately transfer your seeds from their dry container into each hole. Remember, one seed per pot.
4. Using the supplied propagator, sprinkle a 15mm-thick layer of perlite into the bottom of the tray.
5. Place your seed tray into the propagator, adjust the walls, and position the lid. The lid comes with an on/off switch for the already-attached lights.
6. Check the water level in your reservoir once a day. Your aim is to maintain an even level. After 1–7 days, the seeds should have sprouted, with visible leaves appearing. Once the seedling is 3mm tall, transfer it to your final growing medium.
IF IN DOUBT, THINK SPRINGTIME CONDITIONS
No matter which method you choose, always think about what conditions would naturally be like in spring. In their natural environment, cannabis seeds would start to sprout in-line with the seasonal change from winter to spring. Moisture is still high, and temperatures will be naturally rising. Always ask yourself the question, “Does my germination setup replicate spring conditions”. If the answer is yes, there is a good chance germination will be a success.
GIVING YOUR SEEDS THE BEST POSSIBLE START IN LIFE
In most cases, germination will go off without a hitch. However, there are a few troubleshooting issues we can help with.
The first is lighting. Your seed/young seedling will only need fluorescent or CFL grow lights, at least to begin with. While plants need light to thrive, too much of a good thing will damage cannabis in its first few weeks.
Position lights about 15cm from seeds. Once your seedling has developed its first proper leaves (they will have jagged edges), you can move the lights as close as 5cm. If you are concerned about damaging your seedling, place your hand between the leaves and your lights. If you cannot hold your hand in place for ten seconds without it being too hot, move the lights 2cm away. Repeat until you are comfortable with the temperature.
As young seedlings grow quite quickly, you will need to keep adjusting lights to get the best results. After two weeks under fluorescent lights, you will be able to switch to high-powered HPS or MH-style grow lights.
Don’t panic, where possible roots will always grow downwards. It is not necessary to try and reposition the seed yourself. Disturbing the seed at this crucial time will do more damage than good. In most scenarios, what you are actually seeing is not a root protruding from the top of the seed, but the stem of a cannabis plant.
If you are ever unsure, always wait a few days for the first leaves (cotyledons) to appear. As long as a seed’s requirements have been met, the seedling should sort itself out. The best approach is not to panic; follow the golden rules and your young seedling will be ready to transfer to a larger pot in no time.
GERMINATION AND BEYOND
WHEN DO YOU START FEEDING?
It will depend on the growing medium you are using, but in most cases, you will not need to supply any nutrients for the first 2–3 weeks. There will be of plenty of nutrients available in the soil, and even coco will only need nutrients added after a week or so. If you do opt for coco or hydroponics, nutrients should be added at 0.25x their regular strength. Once the first set of leaves appear, increase this in increments of 0.25 per set of leaves. For beginners, we would always recommend using a soil medium. It allows you to get to know the intricacies of growing cannabis more efficiently, and can be the least punishing if you make mistakes.
An easy way to spot if more nutrients are needed is to observe the leaves. The serrated leaves will start to turn pale green as nutrient stores are depleted. Left long enough, leaves will eventually turn yellow. This is a definite sign that more nutrients are needed. Your plant will not die if the leaves turn yellow, but it is a timely reminder to feed your young seedling.
Nitrogen is the most commonly needed nutrient during periods of high growth. Once the seedling has been fed, the colour of the leaves will return to normal. Depending on how long you waited to take action, this can take a few hours or a whole day.
SIT BACK AND RELAX
The first few weeks of a seedling’s development require very little interference. Nutrients, as we have mentioned, will need minor tweaks, as will lighting. However, now that your seed has germinated, you have a few weeks of grace. Sit back, relax, and enjoy your cannabis plant taking shape.
Once those initial weeks have passed, you can treat your seedling like it is in the vegetative stage, and switch to strict lighting routines and full-intensity light. During germination, always remember the golden rules, and if in doubt, ask yourself if you have created “springtime conditions”. If you are confident everything is on track, all you need to do is observe and marvel at the creation of your very own cannabis plant.
Royal Queen Seeds Produces Some Of Europe’s Best Cannabis Seeds, Ensuring Hobby Growers Everywhere Have Access To The Finest Marijuana Strains Around.
Royal Queen Seeds Produces Some Of Europe’s Best Cannabis Seeds, Ensuring Hobby Growers Everywhere Have Access To The Finest Marijuana Strains Around.
Part. 2: The Vegetative Phase. The germinated seeds peak out above ground and immediately spring up.
Part. 3: The Cannabis Blooming Phase. Just another couple of months of blossoming we will be ready to get our sheers out of the cupboard.
Part. 4: The last weeks of flowering stage. After weeks of mounting excitement the long-awaited moment the harvest is finally within arm’s reach.
Part. 5: Harvest Time. Learn every step of the cannabis harvest and post-harvest process.
Time then to whip out our packages of seeds and get to work. But how do you best set to work, to get these tiny, fragile seeds to grow without problems into small plants?
Fail-Proof Cannabis Germination Method
How to Germinate Marijuana Seeds So They Grow Fast
Plus, how to care for new cannabis seedlings…
We have a cannabis seedling germination page which has everything you need to know about all the different germination methods, but this tutorial is different. In this tutorial I’m going to share exactly how I do my seeds from beginning to end! Just follow these instructions and you’ll end up with healthy, fast-growing plants that germinate in just a few days. It’s basically fail proof!
- Soil or Coco (learn how to germinate seeds in hydro)
- A Container
- Rapid Rooters
1.) Get Cannabis Seeds
There are a few different ways to get cannabis seeds, with the most common being ordering seeds online and growing seeds you find in weed that you buy. Learn how to research and find the right strain.
Here’s a picture showing several healthy and viable cannabis seeds
When it comes to new growers, it seems like the most fool-proof method (at least for me, and many of the new growers who write in) is the Paper Towel Method! It’s so simple, but there’s something about wet paper towels that a young seedling loves 🙂 Learn About Other Ways to Germinate Seeds!
Paper Towel Method – Place your seeds inside a folded wet paper towel (Important: use cheap brand!)
This method is hard to mess up if you follow the instructions! Place your seeds inside a folded wet paper towel, and place it between two plates so that the seeds don’t dry out. Surprisingly, the really cheap paper towels work the best because the seeds and roots lay on top without getting stuck to anything. This is important! The more expensive “cloth-like” paper towels (like Viva brand) aren’t good for germination because the roots actually grow into them instead of laying on top.
Wet a paper towel (use the cheapest brand you can find). If growing multiple strains, you may want to label the paper towel so you know which is which. Place each seed on the wet paper towel next to their label.
Cover with another wet paper towel
Add another plate on top to keep the paper towels from drying out
- Check on your seeds every 24 hours but try not to disturb them. When they’ve germinated, you’ll see the seeds have cracked and there are little white roots coming out.
- They should germinate in 1-4 days, though some seeds can take a week or longer (especially older and smaller seeds).
- Keep them warm if possible. One thing you can do to get seeds to germinate a little faster is to keep them in a warm place (75-80°F). Some people use a seedling heat mat but in most cases that’s unnecessary. I leave mine near a sunny window. I usually put a thermometer in the same place to make sure it’s not too hot or cold (or just check the plate with your hands)
Here are those seedlings about 2 days later. Be extra careful when removing the paper towels. Don’t let the seeds roll around or you won’t know which is which! This is when you’ll be glad you used cheap paper towels, as they are much easier to peel off without disturbing your seedlings.
You can see some of the seeds sprouted, but some of them haven’t yet. That’s totally normal! Each seed is different. If this happens to you, you have two choices. You could plant the ones that have already sprouted and let the other ones stay in the paper towels until they germinate. Or you could just put all the seeds in Rapid Rooters now, and hope for the best as far as the slow-sprouting ones. It’s up to you. Letting the unsprouted seeds stay in the paper towels longer improves the germination rate in my experience, but it’s simpler (easier) to move them all at once.
3.) Place Germinated Seed in a Rapid Rooter
Now it’s time to get your Rapid Rooters! Alternatively, you could place your sprouted seeds directly in the final growing medium (coco or soil). I think these help them get started, but I’ve grown many successful plants by just putting the germinated seed directly in its final home.
Rapid Rooters are nice, but not necessary
The Rapid Rooter should be cut open lengthwise. I use big scissors but you could also use a knife.
Gently place the germinated seed inside, root down. Place the seed close to the surface so it doesn’t have far to go.
If you have a root that is curved or bent, don’t try to straighten it out. Open the Rapid Rooter and lay the germinated seed down gently. It will naturally lay on its flattest side. When you slowly close the Rapid Rooter, the bent parts of the root will end up in the “crack” of the Rapid Rooter that you cut to split it open from the side.
Most seedling plugs will go back into place easily, and you’ll barely be able to tell it’s been opened. I love Rapid Rooters because the texture of them causes the seeds to stay in place and not “fall down” further into the hole once you’ve got the Rapid Rooter closed.
4.) Prepare Your Soil, Coco or Hydro Tub
While that’s happening, set up your soil, coco or hydroponic tub if you haven’t already. It will still be a few days until your seedlings arrive, but you want to make sure to have everything ready before the seedlings need to be planted.
If in soil or coco, water your container right after putting your sprouted seed in the Rapid Rooter. This will give it some time to dry out before you install your seedling, so your new roots will have the perfect wet-but-not-too-wet environment in a few days! Remember, seedling roots love a good mix of air and water.
You won’t be watering this thoroughly again for a while to avoid overwatering a young seedling, so by watering thoroughly now, you know there will be some amount of water throughout the whole growing medium.
5.) Water the seedling in the Rapid Rooter until you see a root out bottom, 1-2 days.
Make sure to always keep the Rapid Rooter moist but not soaking wet and give plain, pH’ed water.
Since your seed has already sprouted and been in placed into the right growing position, it’ll often pop its head out within just 12-24 hours! Sometimes you see just the leaves, but often you actually see the seedling push the shell above ground.
Don’t touch the shell! Like a butterfly coming out of a cocoon, the seedlings gain strength during the process of pushing off the shell.
If you manually remove the shell for the seedling too early, you may feel like you’re helping, but sometimes the leaves have trouble opening afterwards. This is because there’s a “film” that can get stuck on the leaves, which would typically come off with the shell but may get stuck to the leaves if the shell comes off early.
Plant leaves still usually “break free” from the film eventually but it just goes to show that sometimes the best thing you can do for your seedlings is have patience and leave them alone. Shells usually falls off naturally as the seedling grows.
That being said, if you have a seedling that’s stuck in a shell for multiple days, sometimes you may need to go in and help. But try to let the seedlings break free from the shells themselves, if possible.
Don’t use a dome on seedlings unless it’s very dry where you live. If you do use a dome, consider keeping a vent open and watching the humidity. A young seedling doesn’t require as high humidity as clones (which are what the domes are designed for), and seedlings tend to get “wet feet” and stop growing as fast in constantly wet conditions.
Water your seeding in the Rapid Rooters until you see a root coming out the bottom. Keep Rapid Rooters moist but not wet. During this time, give seedlings bright, but not too bright light. A fluorescent (CFL) bulb kept several inches away works well! I’ve left mine on the kitchen table next to a sunny window, and that’s also worked fine for me as long as it doesn’t get too hot.
You should see a root come out the bottom in just a day or two!
After you see your first root, it’s time to…
6.) Put Seedling in its New Container!
Dig a hole half the size of the Rapid Rooter, and place your seedling directly inside. You can bury the Rapid Rooter all the way, but having it stick up into the air gives the seedling roots a little extra oxygen while they’re small.
Example of cannabis seedlings growing in coco coir, about to get seedling-strength nutrient water! If these seedlings were in soil, I would be giving just plain, pH’ed water for the first few weeks.
Water immediately with 1-2 cups of water. Give 1 cup in a bigger than 3-gallon container, especially if it still feels wet from when you watered before. Give 2 cups water in a smaller container or drier medium. The reason you would give more in a smaller container (which seems sort of a paradox) is because the moist medium will dry much faster in a smaller container, while a big container will hold onto the water for longer. You’re just trying to avoid putting your seedlings in a situation where their roots stay very wet for more than a day or two, but you also want to avoid letting them ever dry out.
- Coco – water with seedling-strength nutrients, and make sure to pH your water to 5.5-6.5 right before giving it to your plants. Coco does not naturally contain any nutrients, so if you don’t give some from the beginning in the water, each plant only has what was contained in the shell and Rapid Rooter! Seedlings in coco coir grow far faster if you start them off with seedling-strength nutrients from the beginning!
- Soil – water with plain, pH’ed water at 6-7 pH, no nutrients, for the first 3 weeks or so – your plants will be able to live off the nutrients in the soil, and adding extra might be overload and nutrient burn them.
- Hydro – install into your system by putting the Rapid Rooter into your net pot. Learn more about growing hydro. Typically you either water your plants every day until the roots reach the reservoir, or you have a drip feed which waters the plants for you.
How to Water Seedlings in the Beginning
- Don’t water plants until soil or coco is dry up to first knuckle. You want to water your plants every 2-3 days if possible.
- If the growing medium feels dry again within 1 day, give double the amount of water the next time. Otherwise give the same amount again.
- Repeat, until you can give enough water to at least a little runoff, and have it dry in a few days.
- Try to maintain a schedule with you watering your plants every 2-3 days.
- If your growing medium takes longer than 3 days for the top inch to dry, it means the soil is staying wet too long, and plant roots aren’t getting enough oxygen. It also puts your plants at risk of getting fungus gnats. Try giving less water at a time until plant is drinking more. It’s possible you may have a problem with drainage in your medium (what is good soil?) or for some reason water is having a hard time coming out the bottom of the container, for example if there no drainage holes. You also should always make sure to remove runoff water instead of letting the plant sit in it.
- If the medium is drying in less than 2 days, it means you need to give more water to the plant at a time, or possibly transplant to a bigger container if the plant has outgrown its old one.
- Complete guide: How to water cannabis plants perfectly every time
- If seedlings are droopy, how can I tell if it’s caused by overwatering or underwatering?
Autopsy: Why Aren’t My Marijuana Seeds Sprouting?
If your seeds still aren’t sprouting and growing properly, consider the following factors.
If there’s no germination at all…
- Temperature may be too hot or cold – aim for 75-80°F
- Too wet – seeds and seedling roots should always be moist, but should not be soaking wet
- Too dry – if a root dries out the seedling can die!
- Bad seeds – It might not be you, it could be the seeds themselves! Even if you purchase from a good breeder, sometimes you still get duds. How can I tell if seeds are viable?
If seeds sprout, but then stop growing…
- Temperature is too hot or cold – aim for 73-78°F
- Too wet – new seedlings don’t like “wet feet” so make sure your Rapid Rooter or growing medium nevers looks shiny or muddy, as that means there’s too much water! For this reason, it’s also usually recommended to avoid using a humidity dome with seedlings unless your air is dry. Although clones love humidity domes (they need water from the air because they don’t have any roots to get water), seedlings like it a little more dry or roots tend to get mushy.
- Too dry – less common unless you live in a very dry area, but sometimes your medium dries out too fast if you’ve got a heavy-drinking, fast-growing seedling!
- Too much light – if the seedlings get blasted with high levels of light right away, it can shock them. They may need some time to adjust to higher light levels. Simply starting your grow light a little further away that normal is usually enough.Think sunny window at first, and start ramping up after a week of healthy growth.
- Not enough light – if seedlings are growing long and stretchy without growing new sets of leaves, it means it wants more light.
- No light for more than a day – if the sprouted seed doesn’t get light within 24 hours after sprouting, it may die. Once seeds are sprouted, get them in a Rapid Rooter and under at least some amount of light as soon as possible!
- Roots damaged – If somehow your roots got damaged, it can sometimes stop the seedling from growing
Unfortunately sometimes you will never know why certain seeds just don’t thrive! It’s all part of nature 🙂
This marijuana germination tutorial is different. Get exact steps from beginning to end (with pictures!) so your germination goes fast and seedlings start strong!