How to Germinate Cannabis Seeds
An in-depth guide on how to germinate cannabis seeds. Discover different techniques on how to germinate marijuana seeds to ensure a successful cannabis crop.
Everything has a beginning.
Cannabis seeds, like all seeds, must undergo the germination process before it can grow into a weed-yielding beauty.
Countless cannabis germination guides litter the internet. However, none go as in-depth as our seed germination tutorial. Read along to learn how to germinate marijuana seeds like a pro.
You’ll discover everything you need to know about the art of germinating marijuana seeds. From the necessary equipment to different germination methods and everything in between, we’ve got you covered.
The Chemistry Behind Cannabis Seed Germination
Cannabis seeds require the right conditions to sprout.
Without the proper temperature, moisture level, or oxygen saturation, weed seeds will not germinate. Although you can readily germinate seeds outdoors, nothing beats controlled germination indoors.
Let’s take a look at the three primary elements that influence the germination rates of marijuana seeds.
Water is the key player in the process of germinating marijuana seeds.
The outer-layer of the cannabis seed acts as a protective casing that provides a two-fold defense — prevent damage to the inner embryo and prevent minimal moisture from premature germination.
However, if the marijuana seed is saturated with water, it will eventually absorb the moisture and kick-off the germination process.
Once the embryo activates through water saturation, it requires oxygen to jump-start the respiration process. Oxygen fuels respiration, which unlocks food stored within the embryo.
After the respiration process, the embryo consumes the food stores, which in turn produces energy. Energy is the necessary product that propels the germination stage onwards.
Even if cannabis seeds have access to water, oxygen, and energy, it’s all for nothing unless it has access to warmth.
As long as cannabis seeds experience 72-78°F during the initial germination process — they’ll burst forth from the ground and spread their primordial leaves under the sun or artificial light.
The three most important elements for successful weed seed germination
Why It’s Important to Germinate Weed Seeds Indoors
At its core, the germination process lays the foundation of cannabis plants.
Overall, marijuana plants will underperform without proper germination techniques compared to those that experienced ideal conditions during the germination process. Therefore, it’s always best to harness an indoor environment when germinating marijuana seeds.
What to Look For Before Germinating Marijuana Seeds
Before you begin the germination process, there are a few things you must look for.
Let’s take a brief look at each.
Damaged Marijuana Seeds
Ordering feminized or autoflowering cannabis seeds online is the best way to acquire top-shelf genetics.
The seeds, however, may experience a few bumps on the road during the shipping process. With this in mind, you must look over each seed to ensure there isn’t any damage.
As long as each weed seed is undamaged, the germination process will be smooth.
The Cannabis Seed’s Age
Next, it’s a good idea to write down the date on each seed pack once received.
By doing so, you’ll have a clear understanding of a seeds’ age. Like all things, cannabis seeds lose their luster as the years go by. Cannabis seeds may remain viable for decades. However, germination rates decrease over time.
Therefore, you should only germinate seeds that are properly stored for a maximum of 6-months.
The Cannabis Seeds Color
Lastly, you must check the cannabis seed’s color.
Cannabis seeds come in different sizes and exhibit various markings across the outer seed coat. However, the seed’s color is an excellent indicator that represents seed maturity.
In other words, light green to pale white seeds are immature and are likely unviable. Therefore, always make sure that your cannabis seeds are light to dark brown color before germination.
Take a close look at the seeds that you receive for damage or discoloration
Should You Use a Seedling Heat Mat?
Many new cannabis cultivators ask if they should incorporate a seedling heat mat into the equation.
Although seedling heat mats are excellent tools to ensure fast germination, they are not always necessary. Seedling heat mats work by producing a gentle warmth that won’t rapidly dry cannabis seeds during the germination process.
However, they may be overkill if you utilize them during hot days, such as those during the summer months. Alternatively, they are essential during colder months during the winter. Therefore, you can choose to harness a seedling heat mat based on the time of year that you choose to germinate marijuana seeds.
Three Easy Methods To Germinate Cannabis Seeds Indoors
Now that you have a broad understanding of germinating marijuana seeds let’s get some weed seeds poppin‘ with a few different step-by-step tutorials.
You’ll have a better idea of which germination technique to choose once you’re done reading this section.
1. How to Germinate Marijuana Seeds in Soil in Five Easy Steps
If you want to germinate weed seeds au natural — there’s no better option than using soil.
Here’s a list of what you’ll need to germinate cannabis seeds in soil:
- Feminized or autoflowering cannabis seeds
- Eco-friendly “starting” container
- Heat mat (optional)
As you can see, the list above isn’t extensive in the least. In other words, germinating marijuana seeds in soil is incredibly affordable.
First, fill an eco-friendly starting container with soil.
The golden rule? Don’t pack down the soil. Remember, the soil you choose must exhibit a loamy consistency. Hardpack soil does not allow proper water drainage and oxygen circulation, which, as you learned previously, are critical components for the seed germination process.
Furthermore, if you choose to use a heat mat, place the eco-friendly containers on top to warm the medium adequately.
Label each container.
The last thing you want to do is forget what seed you placed into each container — especially if you’re germinating multiple cannabis strains at once.
Now, it’s time to sow the cannabis seed.
Create a small hole that’s roughly 0.25-inches (6mm) deep. Gently place the seed inside the hole and cover it. It does not matter which direction you put the seed — believe us when we say that the seed and gravity will sort things out.
It’s important to note that each eco pot should contain a single cannabis seed.
Gently pour a small amount of water into the area where you buried the cannabis seed.
At this point, you must ensure that the cannabis seed never dries out. Once the germination process begins — there’s no turning back. Therefore, allowing cannabis seeds to dry will guarantee inadequate germination or premature death.
Ultimately, you must monitor the soil and continuously apply water until the seed sprouts.
The final step is patience.
The moment the seed is planted, most beginners ask: how long does it take to germinate cannabis seeds, or how can I germinate my seeds fast?
Healthy cannabis seeds typically break the surface within 2-4-days. Older seeds, however, may take upwards of 12-days to sprout.
The germination phase is an incredibly vulnerable moment for cannabis seeds. Therefore, Do not — we repeat — do not dig up the seed to “check on it.”
This is what you can expect after you successfully germinate your cannabis seeds in soil
2. How to Germinate Marijuana Seeds Using Paper Towels In Five Easy Steps
One of the most popular germination techniques is the paper towel method.
Here’s a list of what you’ll need for this low-budget method:
- Feminized or autoflowering seeds
- Dinner plate
- Paper towels
- Spray bottle
- Heat mat (optional)
Now that you’ve gathered the necessary supplies let’s get crackin‘.
Place two to three sheets of paper towels on top of a clean dinner plate. If you decide to use a heat mat to increase the temperature, place it under the dinner plate.
Label the dinner plate with the name of the cannabis strain of choice.
Place up to 10-seeds per plate.
You must make sure that a minimum of 1-inch adequately separates the seeds.
Spray water on the seeds until the paper towels are completely saturated. Once done, place a new layer of 2-3 paper towel sheets on top of the seeds. Use the spray bottle to soak the new paper towel addition.
Remember: the paper towels must always remain saturated with water. If allowed to dry, the cannabis seeds will fail to germinate.
The germination process should occur within 24-48-hours. After 48-hours, gently peel back the upper paper towel section. If the seeds germinate, you will see cracked-open seeds with an emerging radicle.
At this point, it’s time to move the germinated seed to its new home with a pair of tweezers. This final step requires extreme care because the radicle is fragile, and if broken, the embryo within will die.
Be careful when you use the paper towel method and make sure to label each plate
3. How to Germinate Marijuana Seeds Using Rooting Cubes in Five Easy Steps
Germinating weed seeds with rooting cubes is the ideal method for beginners and professionals alike.
Overall, rooting cubes provide the ease of the paper towel method and the soil technique’s efficiency. Let’s take a look at everything you need to when germinating marijuana seeds with rooting cubes.
- Feminized or autoflowering seeds
- Rooting cubes
- pH 6.0 water
- Rooting tray
- pH meter and pH up or down
- Heat mat (optional)
First and foremost, place the rooting cubes in the rooting tray. If you decide to use a heat mat, place the tray on top.
Next, label each rooting cube or tray with the appropriate name of each cannabis strain.
Use a pH meter and pH solution to achieve a pH of 6.0.
The amount of water you pH depends on the number of rooting cubes. Start with one cup of water if you are germinating less than ten seeds.
Germination cubes require a pH of 6.0 because they are typically made from peat moss, rockwool, or other soilless-based mediums. Therefore, a pH of 6.0 will ensure the best possible results once the seed germinates.
Each rooting cube is equipped with a pre-made hole.
Place one cannabis seed per hole. You may tear off a small piece of the substrate to cover the opening. Once done, saturate the rooting cube with pH 6.0 water.
You must make sure that the rooting cube never dries out. Remember, cannabis seeds must remain moist until they sprout to the surface.
Once again, patience is the final step when you learn how to germinate cannabis seeds with rooting cubes. Overall, cannabis seeds may emerge from the rooting cube within 2-4-days. However, germination may take as long as 7-days.
There are a lot of rooting cubes to choose from, but the germination process remains the same
How to Germinate Old Cannabis Seeds
Now that you understand how to germinate healthy cannabis seeds let’s quickly discover how to germinate old marijuana seeds.
As you become infatuated with the world of cannabis, you’ll soon begin to stack an extensive seed collection. Don’t worry; we’re all seed hoarders at heart because there are so many incredible cannabis genetics out there.
Eventually, however, you’ll notice that you have more than a few old cannabis seeds. Luckily for you — all is not lost.
Here’s our tried and true technique to give your old seeds a boost during the germination process.
Cannabis Seed Scarification
Scarring cannabis seeds is incredibly simple.
All you need is a nail file or a piece of sandpaper. Use the file or sandpaper across the surface of the seed in question. You do not need to use an immense amount of force, but instead, a few good scrapes to scar the seed’s outer shell will do.
The point of seed scarification is to allow water to penetrate the seed coating easily. By doing so, the embryo receives a jump start that initiates the germination process.
Once the seeds are scarred, you may choose one of the three above mentioned techniques to complete the germination process.
A few readily available tools to get your cannabis seed scarification done
The Best Way To Germinate Marijuana Seeds
Now that you’re done reading this guide on seed germination — which method will you choose?
The soil, paper towel, and rooting cube methods are all tried-and-true and provide excellent germination rates. Remember, cannabis seeds are an investment, and you must use the best germination method possible to ensure a healthy cannabis crop.
You have one chance to germinate each seed the right way, and by using this guide, you’ll make each seed count.
What are the Best pH Levels for Growing Cannabis?
Want healthy, productive plants? Dial in your potential hydrogen and you’ll be on your way to a thriving crop. We discuss the importance of achieving the right pH balance with a seasoned growing pro.
The pH and nutrient concentration of a cannabis plant’s medium is a lot like a transistor radio; you have to dial in the right numbers to unlock its full potential.
Whether you are growing with a soil or soilless setup, pH (potential hydrogen) measures the acidity and alkalinity of the medium, which in turn controls the nutrients the plant can absorb.
Students enrolled in the Cannabis Professional Series at Kwantlen Polytechnic University, based in Surrey, British Columbia, learn about the importance of ideal pH levels early in the course.
“It’s something that’s misunderstood, often overlooked, and it’s highly important,” says Nico Hach é , one of the program’s instructors and a horticultural consultant with Root to Shoot Solutions. “People talk about nutrient lockout, that’s generally pH related.”
Soil pH meter – Rukawajung/Shutterstock
Cannabis plants prefer a slightly acidic environment for its roots. Growers using soil as their medium should adjust their pH to a range of 6 to 6.8. For a soilless garden, pH should sit between 5.5 to 6.5.
Allowing a pH range, regardless of the medium, ensures the plant is able to absorb the variety of nutrients required for optimum growth. For example, the plant’s ability to absorb manganese increases with a more acidic medium. Numerous pH and nutrient uptake charts are available online to illustrate the ideal pH for each element needed throughout the vegetative and flowering stages of growth.
“A range allows marijuana to absorb what it likes,” says Hach é. “Your pH doesn’t change your concentration of nutrition, it changes the availability of nutrients. Even though the nutrients are there, they might not be up-taken, or they may be absorbed in excess.”
Young cannabis sativa plant in its first weeks of growing. Yellow leaves could be a sign of chlorosis or unbalanced water pH. – Moha El-Jaw/Shutterstock
While many nutrient companies add pH stabilizers to their products, Hach é recommends frequent water testing to ensure pH remains in the ideal range.
“Water is a big factor that can affect your pH. City water, pond water, or river water, whatever set-up you have, every water source is different,” he says.
Whether or not different cannabis strains thrive under distinctive pH levels is an area that has undergone little scientific scrutiny. Hach é doubts that exploring specific acidity levels based on cannabis species would produce noticeable improvements in yield or quality.
“When you’re talking about changing your acidity like that, it’s complex. Often, they’re hybrid plants, so they’re not true indicas or sativas,” he adds. “It becomes difficult to start playing with that too much.”
However, matching pH to the plant’s natural environment could help promote native characteristics, like terpene profiles.
“When you think of the regions of the world where these plants come from, they’re complete opposites. All the factors would be different,” Hach é says. “Y ou can treat them exactly the same, they’re both marijuana plants, but you could probably be a little more efficient by fine-tuning indicas or sativas.”
Unlike pH, nutrient concentration should be adjusted for different strains of cannabis. The electroconductivity (EC) or total dissolved solids (TDS) are both measurements used to determine the nutrient concentration in your medium.
“You can definitely manipulate how often and how much you feed individual strains,” Hach é said. “The fast-growing plants will be very hungry. You can afford to feed them more and keep pushing them. If you were to do the same to a shorter, slower growing plant, you might push them too much.”
Cannabis plant with tips of the leaves burned by overnutrition. – Moha El-Jaw/Shutterstock
Overfeeding a plant will likely result in nutrient burn, causing the plant’s leaf tips to turn yellow or brown. Left unchecked, nutrient burn will hinder growth and yield. Underfeeding will also affect the plant’s ability to reach its full potential.
To find out what’s right for the strains in your garden, Hach é recommends starting with a low nutrient concentration in the cloning or seed phase of growth. The EC should gradually increase as the plant matures.
“To find out how far you can go, push. It is a matter of trial and error and knowing your plants. Make sure you take notes and keep track,” he said. “There’s also early telltale signs you can see if you’re pushing too much.”
The EC should peak about halfway through the flowering stage of growth.
“With a nine-week flowering or 10-week flowering plant, I would peak around the fourth or fifth week and then begin to tone it down, so you can start your flush at the end. You slowly creep up,” says Hach é.
A gradual increase, as well as a slow decline, in EC will allow you to determine how far you are able to push your plants while avoiding possible shock caused by drastic swings in nutrient concentration.
“Never have big shifts. A change is a stressor,” says Hach é. “C onsistency is key with anything you do with plants.”