You’ve probably noticed by now that there are a few different methods you can choose to germinate your cannabis seeds.
Not all of these methods have the same success rate, and your precious cannabis seeds are expensive to buy.
Therefore, you really want to choose the germination method that’s going to give your seeds the best chance to become beautiful, bud producing plants.
So what is the best way to germinate weed seeds? Read on to find out…
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Best Way To Germinate Weed Seeds
First, take a look at the comparison table below to get an idea of some general success rates for each germination method.
We’ll explore each method in more detail below.
|Germination Method||Success Rating|
|1. Starter plugs & Seedling Cubes||5/5|
|2. Planting directly into the soil||3/5|
|3. Soaking seeds in water||4/5|
|4. Paper towel method||3/5|
1. Starter Cubes & Seedling Plugs
Germinating with starter plugs or cubes is easy and the most reliable method on this list.
What Plugs Should You Use?
Options for starter cubes are seemingly endless, but the majority are made of either Rockwool or peat.
The differences are subtle but very important depending on how you plan to grow your plants after germination.
Peat plugs are an organic option, and sometimes contain a small starter nutrient charge which helps young seedlings after germination.
Rockwool cubes, composed of fibrous wool-like material provide great water and air exchange, which is ideal in hydroponics.
Peat plugs hold more water than air compared to Rockwool cubes, so they aren’t ideal for hydroponic growth.
So, Rockwool or peat? The primary difference comes down to how you will grow the plant after germination.
For hydroponics, Rockwool is the better choice.
For soil/coco/etc., peat plugs generally fare better, but ultimately germination will be nearly identical for these two germination mediums.
Important – If you choose to use Rockwool, make sure to pre-soak the cubes. Use clean (chlorine-free) water that has been set to a pH of 5.5 for 30 minutes to 1 hour. This process lowers the high pH that Rockwool cubes naturally have, your new seedlings will thank you!
How To Germinate With Plugs:
Step 1: After buying your plugs or cubes, soak them in water until they are fully saturated.
Step 2: Place your seed(s) into the pre-cut holes in the plugs. Use some of the plug material to gently cover the opening.
Step 3: Put the plugs into a square box or tray and cover it with a plastic dome. This ensures a high humidity environment, which increases germination success, and helps seedlings along after germination.
2. Planting Directly Into Soil
This method is as old-school as it gets, drop your seeds in some dirt, add water, and you’re done.
If only it were that easy!
Unfortunately, it’s not quite so simple.
There are lots of factors that go into this method, and each must be nearly perfect for germination to occur.
How to germinate seeds directly in soil:
Step 1: Purchase quality soil from a reputable source. You want to soil with good drainage, this allows for air exchange; seeds need moisture but you don’t want to drown them.
IMPORTANT: Never use dirt from outside. It will contain no shortage of nasty stuff (diseases, pests) which will kill or stunt your seedlings.
Step 2: Now, you need to plant your seeds at the right depth. A good rule of thumb is to plant seeds 2 times deeper than the width of the seed.
Step 3: Provide water for your seeds by soaking your container in a tray containing about an inch of water. This allows the soil to be moistened uniformly, preventing over-watering. This also keeps the seed in the perfect place for germination to occur.
Check out this method in action:
This method allows you to start your seed directly in your planting medium, but if you aren’t careful with this technique, you can run into trouble.
Seeds need air and water to germinate, if there’s too much of one, the other falls short, preventing germination.
If planted too deep, the energy available to the seedling won’t be enough for it to break the surface.
This will essentially starve and kill your seedling.
If you don’t plant deep enough, the seedling may dry out, or never become moist enough to germinate.
3. Soaking Seeds in Water
This method is not so much away to fully germinate your seeds, but rather ensures rapid and reliable germination.
As mentioned in the previous methods, seeds need water to germinate.
This method involves placing seeds in a container filled with water rather than into a plug or the soil.
How to start germination with water:
Step 1: Place your seeds in a container of clean water and allow to soak overnight, or for at least 12 hours.
Tip: Soaking seeds allows the seed to begin absorbing water. Water absorption is the first step in germination and is required for seeds to germinate.
Tip: Do not soak seeds for more than 24 hours, they can become oxygen-deprived and die. Shorter soaking times are always preferred.
Step 2: After soaking at least 12 hours, use sterilized tweezers or clean hands to remove the seeds. Immediately place the seeds into your medium, such as a plug or soil.
Tip: At this point, gently tap your seeds if they are still floating, and monitor which sink and which float. Sunken seeds indicate they are full of water, which is what we want. Floating seeds have not absorbed water, and likely won’t ever, meaning that they are unlikely to germinate.
Check out this method in action:
Why does this work?
This method increases germination rates because the seed is primed, it’s already absorbed water and broken dormancy, so is ready to push out its first roots.
4. Paper Towel Method
The paper towel method is similar to soaking seeds in water, but this method will germinate your seeds to the point where the taproot has emerged.
How to germinate seeds with paper towels:
Step 1: Place a folded wet paper towel into a plastic container, or on a plate.
Step 2: Place your seeds on the paper towel with adequate space between them. Cover the seeds with another folded wet paper towel.
Tip: Don’t wet the paper towel to the point where it’s dripping and sopping wet. Just lightly wet each paper towel until damp.
Step 3: Put a lid or plastic wrap on the container, or another plate on the plate. Seal the container but leave a small hole for air exchange.
Step 4: Place your plates or container in a warm (70-80F / 21-26C) and dark environment
Like soaking the seeds in water, this method provides lots of water to the seeds to start germination.
But it also allows enough air exchange for the seed to produce a taproot and begin growing into a seedling.
Check out this method in action:
This method helps to increase the chances of germination and seedling success but can introduce some extra issues.
- Once seeds have germinated, they may grow into the paper towel, making removal difficult and potentially damaging the fragile seedlings.
- The paper towels and the container you use for germination must be sterile. This is nearly impossible, so you are likely to grow more than seedlings (i.e. fungus) with this method.
- The extra handling of sprouted seedlings is the biggest issue with this method. Even if you’re very clean and careful with your seedlings, it is extremely easy to damage or contaminate them. Contamination and early damage can ultimately stunt or kill your baby plants.
So what is the best way to germinate weed seeds?
After examining each method, if you absolutely had to pick one, it would be starter cubes and seedling plugs.
If you consider everything that can go wrong when germinating seeds, this method does the most to remove potential pitfalls.
- It’s relatively fool-proof because the cubes can only hold so much water, so no overwatering.
- The pre-drilled holes are not too deep or too shallow for cannabis seeds.
- The cubes/plugs hold moisture for long enough time to allow for the seeds to take up water. They also won’t dry out too quickly.
- They provide a soft medium for young roots to push through.
But the best way to germinate weed seeds would really be a combination of these methods.
Use either the paper towel or water soaking method to get your seeds to uptake water.
Next, transition them to either soil or plugs.
This gives you the advantages of each method, with the least downside of each.
Here are a few extra tips to follow when trying to germinate your cannabis seeds:
- Keep temperatures in the area you are germinating seeds between 70-80F (21-26C)
- Germinate seeds in total darkness
- Don’t use hard tap water (ppm above 120), it can damage the seed
- Avoid using chlorinated tap water, it can damage or kill microbes that help young seedlings develop
- Don’t add nutrients to the water when germinating seeds, the seeds already contain all the nutrients they need
- When seeds germinate, don’t put them under intense light (HID or sunlight), the seedlings will burn and/or dry out
- Provide non-intense light (i.e. T-5 fluorescent light) for seedlings as soon as they emerge, this will prevent stretching