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.
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?
Planting Autoflowering Cannabis Seeds
Planting autoflowering cannabis seeds is a relatively easy process, but to get the most out of your plants you need to follow a series of steps that are completely different from those that seasonal seeds have. An autoflowering cannabis seed needs a bit more care than normal seeds. You need to speed up the growth as much as possible so you don’t get teeny plants with no more than 5 blunts on them. We’re going to give you a series of things you’ll need to do in order to get the most out of your plants.
Germinating Autoflowering Cannabis Seeds:
The first thing that you’ll need to do is germinate the seed properly, using the paper towel method that we’ve talked about here before.
Once your seeds have germinated or opened, however you prefer to call it, you’ll need to prepare some small Teku 7×7 pots with soil, don’t use jiffy pellets or anything like that as the roots need plenty of space to grow.
Fill the pots with soil first and then water them; once the plant breaches the top of the soil you mustn’t wet it again. If you water it before the seed has come out then it will probably move up towards the surface which can cause a whole list of other issues. The best thing to do is to water first and then wait to water it again until the sapling grows a bit.
Bury the seed about half a cm to 1cm down into the soil, making a hole with a pen or a toothpick and putting the seed inside with the little root facing downwards. Cover it with a bit of soil without compacting it too much and leave it there until the plant begins to grow above the soil. What we usually do is leave it for 24h with light during this process until you transplant the seed to its main flowerpot. If you don’t have grow lights then use the most powerful one you can so that it doesn’t get too cold in the pot.
Up until this point the process has been exactly the same for seasonal seeds, but that’s about to change. You’ll need to wait for the plant to break the surface and have that little growth spurt that cannabis plants tend to get when they’re looking for light. This can take 4 or 5 days, and you’ll need to keep a close eye on them so you don’t leave them for too long. Make sure that the plant doesn’t begin to develop in that flowerpot, the maximum time you should leave the plant in it is 6 days.
Now is when you’ll need to transplant your autoflowering plants to their permanent home. Autoflowering strains that take two months prefer pots that are about 7L, whereas those that take three months much prefer pots that are 11L, no bigger.
Fill the flowerpots to the top with soil, nice and compact so that when you water the water doesn’t go all the way to the bottom, although make sure you don’t compact it too much as the plants need a good oxygen/water ratio to breath and grow; with no oxygen the roots won’t be healthy at all and you’ll end up with a dwarfed plant. You’ll need to keep the light at 20h until the end, or make sure it’s in a spot where it can get the maximum amount of sunlight hours.
Once those pots are full of soil, you’ll need to make a hole to stick your small plant in. Make it deep, as you’ll need to bury part of the trunk as well, to the point where the bottom of the trunk is just 5cm long from the soil to where the first leaves are. Then, water the edges of the pot little by little so the soil gets properly humid.
The reason you need to bury part of the trunk is because even more roots can come out of that small piece of stem, and it also gives the plant stability and strength so that it doesn’t bend and break and it can spend more energy on growing branches and foliage. The more roots it grows the more the plant will grow, which is how you can easily speed up the growing process. Once you’ve buried it, water the plant with about a liter of water mixed with a low concentration of growth fertilizer; some substrates absorb water easier than others, so it might be trial and error in your case and you’ll need to adapt the amount of water to how absorbent your soil is.
I use a liter of water with Canna Terra Professional, and no excess water comes out of the holes in the flowerpot which means it’s adequately watered. You can read all about substrates here.
From this day onwards you’re going to need to check and see if the soil is dry; until it is completely dry you shouldn’t have to water it again, and this should take about 7 days. The best way to check if the soil is dry is by lifting up the pot; if it’s still pretty heavy then it still has water in it.
The next step is watering with growth fertilizers once it’s dry after that first watering. You should be at around day 13 or 14 and you’ll have noticed a bit of growth in the last couple of days. For watering, you should make your mix in a bottle with just one glass of water per pot at this stage. The next day check and see if the pots are heavy; if they’re dry then give them another glass of water but if they’re not don’t water them again until the next day. If the soil is extremely dry the next day then you’ll need to give it two glasses of water. Up the dosage as time goes by little by little and this process of dryness and water will make the plant grow a nice root system, as well as an amazing production.
Before you realize it, it will be day 25 and your plant should be beginning to flower. It no longer looks like the plants you had before, does it? You haven’t changed the seeds, just the method. Now all you have to do is follow the typical flowering steps that every seed needs; a flowering stimulant to begin with, a flowering base, a fattening products once the buds have formed, and end it all by washing out the roots. Flowers take about 20 days to properly form and the fattening period lasts about 2 weeks rather than four weeks for a seasonal seed; once you see the flowers forming properly then you need to use the fattening product.
We’re sure that if you follow these steps you’ll be extremely happy with the results that your autoflowering plants will give you compared to other grows you’ve tried. You might even see some of the mistakes that you made corrected in this article. Many people will probably say to never transplant autoflowering plants, but those people won’t get specimens as big as you will if you follow this guide!
You can find a wide range of cannabis seeds by clicking here.
Author: Javier Chinesta
Translation: Ciara Murphy
A complete guide to planting autoflowering cannabis seeds; get the most out of your plants with these fool proof steps to growing autoflowering strains.