Every grower knows that before you can harvest some big and fragrant cannabis buds, your plants need to go through several growing stages, starting with the sprouting or germination of the seeds, as it marks the beginning of your plant’s life cycle. The following weeks are when the other stages come into play, as you learn to navigate through them and provide your plants with everything they need for a successful season.
The very first step is learning how to properly sprout or germinate your cannabis plants to help them develop into strong and healthy plants. Therefore, in this article, we’ll talk about how to sprout or germinate cannabis seeds and we’ll give you some tips for completing the process successfully.
Sprouting the Seeds – The Beginning of the Life Cycle of Marijuana Plants
Seed germination (or sprouting) refers to the end of the hibernation process of the cannabis seeds and the beginning of their growth. When the temperature and moisture levels in the air start to change in the springtime, it prompts them to end their winter slumber and start developing new growth. Soon after, the first cotyledons become visible and the rest is history.
When choosing seeds from a seed bank, it’s important to choose high-quality ones as their genetic makeup will play a crucial role in the quality of your harvest. The darker the seeds, the better they are. Pale, green, white seeds, or seeds that are too dark, will likely not be viable for sprouting.
Whichever Indica or Sativa you choose, we recommend you buy feminized seeds if you can, as they only produce female plants that will give you seedless buds. This will save you the trouble of removing the male plants once their gender is revealed to prevent them from pollinating the female plants.
The germination process is the same for both photoperiod and autoflowering seeds, but you will need to meet the basic requirements so that you can start the process successfully.
What Cannabis Seeds Need for a Successful Germination Process
In order to achieve successful germination, you need to provide the cannabis seeds with the following requirements:
- Enough moisture. Moisture makes the seeds swell and increase in size, giving them an incentive to soften and start sprouting. Remember that you should keep the environment moist, but not soaking wet;
- Warmth. In nature, cannabis normally starts sprouting in the springtime, so it makes sense that the seeds would need warmth in order to sprout. Put them in a warm place with a temperature between 71-77 degrees Fahrenheit where they can sprout comfortably;
- Relative humidity. Cannabis seeds need a humid environment in order to thrive. The ideal relative humidity for germination is somewhere between 70% and 90%. Young seedlings need humidity so they can absorb the moisture from the air and continue to thrive;
- Don’t disturb them. Once you leave your cannabis seeds to germinate, avoid touching them or repositioning them when you check on them. Unless you need to add more moisture or fix something, it’s best to not tamper with them as they will be very fragile.
Different Methods for Germinating Cannabis Seeds
There are three basic germination methods that are the most commonly used by cannabis growers and all of them will be successful if you provide the seeds with their basic requirements.
The Paper Towel Method
The paper towel method may be the most well-known germination method of all. The paper towel method requires you to sprout the seeds outside the growing medium and plant them once they have developed the taproot.
For this method, you will need some paper towels and two plates. It’s best to use cheap, nonporous paper towels because the more expensive ones are more porous and the taproot can get stuck on them instead of lying on top.
- Moisten a couple of paper towel sheets and place them on a plate. Put the cannabis seeds on top but don’t crowd them, leave about an inch between them so they have enough room to sprout;
- Then, cover the seeds with another layer of moist paper towel sheets and place the other plate on top;
- Place them away from light and in a warm place (about 72 degrees Fahrenheit). The paper towels shouldn’t dry out, so you should check on the seeds regularly to moisten them again;
- The seeds will need 1-4 days to germinate, or even up to a week if they’re older seeds.
After they have sprouted, be very careful when you pot them in their growing medium. Don’t touch the white root with your bare hands because it will be very delicate. It’s best to handle the seeds gently and use tweezers.
Germinating Directly in Soil
Germinating the seeds directly in soil lowers the chances of potentially damaging the taproots when you plant them, making it the safest method. The soil will immediately provide the young seedlings with nutrients and it will maintain a stable temperature.
Growers usually start the seeds in small pots filled with high-quality soil and then transplant the plants into bigger containers once they have outgrown the small pots.
- The best way to do this is to create a few knuckle-deep holes in the soil (about half an inch deep) and lightly moisten them. The soil shouldn’t be wet as excess water will make it hard for the seeds to sprout;
- Then, place the seeds in the holes and cover them loosely with soil. Don’t pack the soil into the holes, or else the delicate taproot will have a hard time pushing through and navigating through the soil;
- Keep the soil moist by occasionally misting it with water whenever you notice it’s gone a bit dry;
- After about 4-10 days you should notice the first leaves (also called cotyledon leaves), meaning that the germination is complete.
After a few weeks, when the young seedlings have grown three or four inches, it’ll be time to transplant them into bigger pots and prepare for the vegetation stage.
Soaking the Seeds in Water
This method isn’t always successful, but given the right conditions, it could germinate the seeds faster than both the soil and the paper towel methods because the water softens the shell. It’s also good for older seeds because the water can revive them.
For this method, you will need to fill a glass with tap water and let it sit at room temperature (about 65 degrees Fahrenheit). Then, put no more than three seeds per glass and let them sit at room temperature. If all goes well, they should sprout in about 24-48 hours, but it can take up to a week for older seeds. If you need to leave them for longer, change the water every couple of days and maintain it at room temperature.
Seeds that have sunk to the bottom after 12 hours will likely germinate, while those that have stayed afloat either need more time or they probably won’t germinate. If the seeds haven’t sprouted after a week, don’t give up. Just switch to the paper towel method as a last resort. If that doesn’t succeed either, just try again with different seeds.
Germinating Seeds in Starter Materials
To simplify things, you can also use starter materials, such as cubes or plugs. These methods don’t always guarantee success, but are certainly worth trying. The process is very simple – you just add the seed in the plug or cube, add some water, and wait for the seeds to sprout. This method also saves the seeds from transplantation shock and reduces the risk of damaging the white roots.
Rockwool cubes are commonly used by hydroponic growers because they work great in hydroponic setups – they’re able to hold enough moisture and are resistant to microbial growth. They are very affordable and easy to find, but they can be a challenge for novice growers.
First of all, Rockwool cubes need to be soaked in water for at least 24 hours because their pH is much higher than what marijuana seeds need. After soaking, you will need to let them dry out for a few days before you plant the seeds there because they will likely hold a lot of water.
You should know that Rockwool is an inorganic material made from molten lava spun into thin threads and it’s not biodegradable. It’s also a health hazard and can be dangerous if you inhale small particles of Rockwool dust. Therefore, you should always protect your hands, eyes, and mouth when you handle it.
Peat pellets (or Jiffy pellets, by the brand) offer much higher germination rates than Rockwool cubes. They are made from partly decomposed vegetable matter and are compressed into small cubes. Peat pellets are not suitable for hydroponic setups where the growing medium is water, but they are great for soil or hydro mediums such as coco coir.
Peat pellets are already optimized for germination, making them very suitable for beginners. Their pH is 5.5 and they already have a small dent for the seed. They come dried when you buy them, so before you use them, you should soak them in lukewarm water to let them expand. Once they have expanded, squeeze the excess water and place the seed in the small dent in the middle.
When the seeds sprout and the white root becomes visible, you can transfer them directly to potting soil or coco coir (or even Rockwool).
What Happens After the Marijuana Seeds Have Germinated?
Unless you sprouted the seeds in the soil, you will need to eventually transplant them to their new home with the growing medium of your choice. At this point, you can transplant the germinated seeds in potting soil, a hydro medium such as coco coir or Rockwool, or a hydroponic setup.
The transplanting should be done with utmost care. Make sure your hands are clean to avoid contamination, or even better, use tweezers when you transfer the sprouted seeds to their growing medium.
Avoid placing the pots on the windowsill as the light will be too strong. Instead, opt for grow lights such as compact fluorescent lightbulbs (CFL) because they don’t produce too much heat. Place them at 6 or 7 inches away from the pot because young plants are still fragile and you don’t want to risk burning them.
Using a spraying bottle to water the plants for the first few days is ideal to prevent overwatering. Your newly-sprouted plants will still be in a fragile state so excess water can only damage them.
The Takeaway – Warmth and Moisture Are Imperative
Sprouting marijuana seeds is the beginning of your journey and will set the course for the rest of the process. In order to create the perfect conditions for the seeds, adjust the temperature accordingly and make sure there is enough moisture in the environment.
The paper towel method seems to be the most popular one, but if you’re a beginner and are afraid of messing up during the transplantation process, you can germinate them directly in soil or in Jiffy pellets.
Finally, wait until the cotyledons have formed before using any grow lights, and use them sparingly at the beginning so as to not overwhelm the young plants. Maintain good relative humidity and temperature and feed your plants – and you’ll soon start seeing progress.