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.
Cannabis seeds 101: How to grow marijuana from seed
Cannabis is grown from one of two sources: a seed or a clone. Seeds carry genetic information from two parent plants and can express many different combinations of traits: some from the mother, some from the father, and some traits from both.
In commercial cannabis production, generally, growers will plant many seeds of one strain and choose the best plant. They will then take clones from that individual plant, which allows for consistent genetics for mass production.
If cannabis is legal in your state, you can buy seeds or clones from a local dispensary, or online through various seed banks.
Cannabis seeds vs. clones
For the typical homegrower, it may be easier to obtain cannabis seeds rather than clones. Growing from seed can produce a stronger plant with more solid genetics.
Plants grown from seed can be more hearty as young plants when compared to clones, mainly because seeds have a strong taproot. You can plant seeds directly into an outdoor garden in early spring, even in cool, wet climates.
If growing outside, some growers prefer to germinate seeds inside because they are delicate in the beginning stages of growth. Indoors, you can give weed seedlings supplemental light to help them along, and then transplant them outside when big enough.
Most seeds that you will buy are regular seeds as described above, but here are a couple more types.
How weed seeds work
Cannabis can be either male or female—also called “dioecious”—but only females produce the buds we all know and love. For reproduction, males have pollen sacs and pollinate females, causing female flowers to produce seeds.
Once cannabis seeds are mature, the female plant begins to die, and seeds are either dropped to the ground where they grow into new cannabis plants next spring, or the seeds are harvested for processing into seed oil or food products, or stored so they can be sown in the ground later and become the next generation of plants.
To get the buds found in medical and recreational stores, female cannabis plants are grown in an environment without males—or the males are removed from the area before they release pollen—so the females don’t create seeds. Females can then focus their energies on producing buds and not seeds—this high-potency marijuana is traditionally known as “sinsemilla,” meaning “seedless.”
Some varieties of cannabis can produce male parts alongside female flowers on the same plant, especially if exposed to environmental stressors. These plants are known as hermaphrodites, and sometimes they can self-pollinate to create seeds.
Pros and cons of using cannabis seeds
Check out Johanna’s full video series on how to grow weed on Leafly’s YouTube .
If buying from a reputable breeder or seed bank, growing from seed is the best way to ensure your plants will have solid genetics and start clean, meaning they won’t come with diseases or pests.
Also, buying from a reputable breeder or seed bank will give you a sense of what a particular strain will look and smell like, how it will grow, and how much it will yield at harvest.
The main drawback to growing from seed is there is no guarantee as to what you’ll end up with—if you buy a regular pack of cannabis seeds, it will be a mix of males and females. You’ll need to sex them out (more below) to identify the males and get rid of them, because you don’t want your females producing seeds.
Sexing marijuana plants can be a time-consuming process, and if you don’t catch males, there is a risk that even one males can pollinate your entire crop, causing all of your female weed plants to produce seeds.
One way to avoid sexing plants is to buy feminized seeds (more below), which ensures every seed you plant will be a bud-producing female.
You can also minimize headaches and avoid the hassle of seed germination and sexing plants by starting with clones.
How weed clones work
Aside from producing cannabis through seeds, or sexual reproduction, you can also reproduce the plant through cloning, or asexual reproduction. A clone is a cutting that is genetically identical to the plant it was taken from—that plant is known as the “mother.”
Pros and cons of using cannabis clones
Through cloning, you can create a new harvest with exact replicas of your favorite plant. Because genetics are identical, a clone will give you a plant with the same characteristics as the mother, such as flavor, cannabinoid profile, yield, grow time, etc. So if you come across a specific strain or phenotype you really like, you might want to clone it to reproduce more buds that have the same effects and characteristics.
With cloning, you don’t have to get new seeds every time you want to grow another plant—you just take a cutting of the old plant—and you don’t have to germinate seeds or sex them out and get rid of the males.
One drawback of clones is they need to be taken during the vegetative stage of a plant—flower is too late—so if you have a small setup with only one light, it can be hard to keep clones alive while flowering other plants, because the two need different amounts of light.
Another drawback to clones is they can take on negative traits from the mother plant as well. If the mother has a disease, attracts pests, or grows weak branches, its clones will probably have the same issues.
Additionally, every long-time grower will tell you that clones degrade over time.
What are feminized cannabis seeds?
Feminized cannabis seeds will produce only female plants for getting buds, so there is no need to remove males or worry about female plants getting pollinated. Feminized seeds are produced by causing the monoecious condition in a female cannabis plant—the resulting seeds are nearly identical to the self-pollinated female parent, as only one set of genes is present.
This is sometimes referred to as “cloning by seed” and will not produce any male plants. This is achieved through several methods:
- By spraying the plant with a solution of colloidal silver, a liquid containing tiny particles of silver
- Through a method known as rodelization, in which a female plant pushed past maturity can pollinate another female
- Spraying seeds with gibberellic acid, a hormone that triggers germination (this is much less common)
Most experienced or commercial growers will not use feminized seeds because they only contain one set of genes, and these should never be used for breeding purposes. However, a lot of beginning growers start with feminized seeds because they eliminate the worry of having to deal with male plants.
Top feminized cannabis strain families
A lot of classic weed strains that have been around for a while come in feminized form. Some popular fem seeds are:
- OG Kush
- GSC (Cookies)
What are autoflowering cannabis seeds?
Autoflowering seeds are also popular with beginning growers. They are easy to grow because you don’t have to worry about light cycles and how much light a plant receives.
Most cannabis plants begin flowering when the amount of light they receive on a daily basis reduces. Outdoors, this happens when the sun starts setting earlier in the day as the season turns from summer to autumn. Indoor growers can control when a plant flowers by reducing the daily amount of light plants receive from 18 hours to 12 hours.
However, a type of cannabis called Cannabis ruderalis, which developed in extreme northern conditions without much sunlight, will begin flowering once the plant reaches a certain age—they automatically start flowering regardless of the amount of light they receive, hence the name “autoflower.”
Pros and cons of growing autoflower
Because they grow and flower quicker, growers can fit in multiple autoflower cannabis harvests into the span of one regular harvest.
Autoflowers can be started in early spring and will flower during the longest days of summer, taking advantage of high quality light to get bigger yields. Or, if you get a late start in the growing season, you can start autoflowers in May or June and harvest in the fall.
Also, autoflower plants are small—perfect for closet grows or any small grow, or growing outdoors where you don’t want your neighbors to see what you’re up to.
A couple big drawbacks, though: Autoflower strains are known for being less potent. Also, because they are small in stature, they usually don’t produce big yields.
However, potency in autoflowering varieties has increased significantly since their initial introduction, with some breeders crossbreeding the low-THC ruderalis with other more potent varieties.
Tips for growing autoflower marijuana seeds
Autoflowering strains require some preparation, as they will grow quickly and start to flower whether or not you’re ready for them.
Many marijuana growers start autoflowers early in the season, and at a different time than a regular crop, so keep the season and climate in mind when growing and harvesting—your plants still need warmth to grow, and rain can give them bud rot. Consider growing in a greenhouse to protect them.
Because training happens during vegetative growth, for autoflowering plants, this period could be as short as a few weeks, which means time is limited. Try topping your autoflowers after they have three nodes, and stop once they begin to flower. You will want to prune them lightly.
Go easy on nutrients
Autoflowers don’t need lots of nutrients because they’re small and don’t spend much time in the vegetative cycle. They won’t need as much veg nutrients—such as nitrogen—but will need more bloom nutrients.
What are high-CBD cannabis seeds?
CBD, or cannabidiol, is one of the chemical components—known collectively as cannabinoids—found in the cannabis plant. Over the years, humans have selected plants for high-THC content, making cannabis with high levels of CBD rare. The genetic pathways through which THC is synthesized by the plant are different than those for CBD production.
Cannabis used for hemp production has been selected for other traits, including a low THC content, so as to comply with the 2018 Farm Bill. Consequently, many varieties of hemp produce significant quantities of CBD.
As interest in CBD as a medicine has grown, many breeders have crossed high-CBD hemp with cannabis. These strains have little or no THC, 1:1 ratios of THC and CBD, or some have a high-THC content along with significant amounts of CBD (3% or more).
Seeds for these varieties are now widely available online and through dispensaries. It should be noted, however, that any plant grown from these seeds is not guaranteed to produce high levels of CBD, as it takes many years to create a seed line that produces consistent results. A grower looking to produce cannabis with a certain THC to CBD ratio will need to grow from a tested and proven clone or seed.
How to germinate marijuana seeds
Germination is the process in which a seed sprouts and begins to grow into a new plant. Also referred to as “popping,” germination is the very first step in starting your weed grow.
Marijuana seeds can be acquired from an array of sources and can vary in quality. For more info on how to buy marijuana seeds, check out our Guide to buying cannabis seeds.
Cannabis seeds require three things to germinate: water, heat, and air. There are many methods to germinate seeds, but for the most common and simplest method, you will need:
- Two clean plates
- Four paper towels
- Distilled water
Take four sheets of paper towels and soak them with distilled water. The towels should be soaked but shouldn’t have excess water running off.
Take two of the paper towels and place them on a plate. Then, place the marijuana seeds at least an inch apart from each other and cover them with the remaining two water-soaked paper towels.
To create a dark, protected space, take another plate and flip it over to cover the seeds, like a dome.
Make sure the area the seeds are in is warm, somewhere between 70-85°F.
After completing these steps, it’s time to wait. Check the paper towels once a day to make sure they’re still saturated, and if they are losing moisture, apply more water to keep the seeds happy.
Some seeds germinate very rapidly while others can take a while, but generally, seeds should germinate in 3-10 days. If it’s been two weeks and a seed hasn’t sprouted, it’s probably a dud and won’t sprout.
A seed has germinated once the seed splits and a single sprout appears. The sprout is the taproot, which will become the main stem of the plant, and seeing it is a sign of successful germination.
It’s important to keep the delicate seed sterile, so don’t touch the seed or taproot as it begins to split.
Transplanting germinated cannabis seeds
Once you see the taproot, it’s time to transfer your germinated seed into its growing medium, such as soil.
- Fill a 4-inch or one-gallon pot with loose, airy potting soil
- Water the soil before you put the seed in; it should be wet but not drenched
- Poke a hole in the soil with a pen or pencil—the rule of thumb is: make the hole twice as deep as the seed is wide
- Using a pair of tweezers, gently place the seed in the hole with the taproot facing down
- Lightly cover it with soil
Keep a close eye on the temperature and moisture level of the soil to keep the seed happy. It’s very delicate at this stage. Use a spray bottle to water it—over-watering can suffocate and kill the delicate sprout.
Within a week or so you should see a seedling begin to grow from the soil.
Germinating cannabis seeds doesn’t always go as planned. Some seeds will be duds. Others will be slow and take longer to sprout. But some will pop quickly and grow rapidly.
This is the beauty of seeds—often, you can tell which plants or genetics will thrive right from the get-go. This will help you determine which plants you want to take cuttings from for clones or for breeding if you want to create a seed bank of your own.
How to sex a pot plant
Check out Johanna’s full video series on how to grow weed on Leafly’s YouTube .
As we’ve mentioned, cannabis is a dioecious plant, meaning male and female reproductive organs appear on different plants.
Because only female cannabis plants produce buds and you want them to focus all their energy on producing buds and not seeds, it’s important to identify and get rid of male weed plants so they don’t pollinate females. If females are pollinated, it will give you buds filled with seeds, making your weed harsh and unpleasant.
Cultivating males is important for breeders trying to cross new strains and genetics, but most people growing for buds will want to remove the males.
As mentioned above, you can skip the processing of sexing weed plants by growing with feminized seeds or clones.
If growing male and female cannabis seeds, they’ll start to show their sex organs, or “pre-flowers,” after 8-10 weeks from germination.
Cannabis plant sex organs appear on nodes, the points where branches grow off from the main stalk.
Males will have round balls—these will develop into pollen sacs, which will release pollen into the air when mature.
Females will have a round structure with long hairs—these hairs will develop into pistils, which will catch pollen in the air.
Pre-flowers can initially be extremely small and hard to identify with the naked eye, but you can use a magnifying glass to get a better look.
Can I grow a seed I found in a bag of weed?
Finding a cannabis seed in your stash is not ideal, but we’ve all been there before. Although much less common than it once was, it still happens. Sometimes you’ll notice one when grinding down some flower, or you’ll see one pop, spark, and crackle from the heat of a lit bowl.
These are referred to as “bagseeds” and whether or not you can grow one will depend on where it came from.
Is a bagseed good or bad?
Seeds found in finished cannabis buds can develop for a number of reasons. For example, a male plant may have accidentally pollinated a flowering female during the growing process. But more commonly, they’re a sign of stress and can be attributed to high temperatures during the final stages of flowering or an exaggerated spike in climate or environment.
Seeds can also form in plants with genetic disorders or instability, like hermaphrodites—plants that develop both male and female reproductive parts. Generally, stress and genetic disorders are viewed as bad, so temper expectations with any plant you start from a bagseed.
But sometimes you get lucky and find a mature seed in some really nice herb. Strains like the legendary Chemdog wouldn’t be possible without adventurous smokers planting and proliferating the seeds they found in a bag of kind bud.
So don’t discount bud because it has a seed or two in it. While not ideal, it could be the origins of the next great weed strain.
Ask yourself a few questions to decide if it’s worth the time and energy to grow the seed.
Was the seed found in good weed?
If you don’t like the flavor, effects, or even the look of the bud, then it’s probably not worth growing.
Are you ready to grow?
Growing marijuana takes a certain level of commitment: time, energy, and financial resources, so be sure you can commit to the whole process.
Is the seed viable?
For a seed to be viable, it must be mature enough to have a completely formed genetic blueprint, and it must be strong enough to germinate and pop through its hard casing and sprout its crucial taproot.
There are a few indicators that will give you a sense of whether the seed is worth germinating.
- Tiger stripes—dark stripes on the seed which resemble veins on a leaf are generally good
- Solid shell—a seed should be able to withstand a little pressure when pinched between your fingers; if it crumbles or cracks, it’s no good
Immature seeds tend to be light in color and have a soft outer shell.
In some cases, even if a seed isn’t completely mature, there’s still a chance it could be viable. But often these are extremely weak, take long to develop, and express other unfavorable characteristics. Growers usually discard weak plants to free up space.
You might also find a mature seed that has been physically damaged through poor handling, like rough trimming. In those cases, it probably isn’t worth the effort to try and germinate the seed.
But if the seed you found looks decent, you might as well germinate it and see what sprouts.
Time to germinate
Viable or not, there’s only one sure way to find out if a bagseed will grow. If you’re simply curious to learn and not as concerned with the overall outcome, you can plant a couple of bagseeds outside and see what happens.
If you’re ready for a more serious approach, make sure you have the space for a proper garden and pop the seeds to see what fruit they bear.
Even if your seed sprouts fast and grows vigorously, it still has roughly a 50/50 chance of being female and producing buds, instead of turning out to be a male.
Remember, once a seed germinates, the real work begins. Sexing, selecting, vegetative growth, flowering, and the eventual harvest all lie ahead.
How to buy cannabis seeds
Cannabis seeds can be found on numerous online seed banks, but note that it is illegal to bring seeds into the US and Customs will seize any cannabis seeds that they find in packages or on a person. In legal and medical states, you may purchase seeds at a dispensary.
How to Germinate a Bag Seed
F inding a seed in your bag of weed used to be regarded as an insult, an indication you scored some inferior product. But it’s a new millennium, and growing cannabis is perfectly legal in some states and territories. While buying seeds online is still recommended for reasons we will detail further, finding a healthy seed can be as valuable as an ounce of gold. Or at least the cost of the bag.
- Can You Tell if a Cannabis Seed is Male or Female?
- How to Store Marijuana Seeds Properly
- Feminized Cannabis Seeds Explained
- How to Start Seeds
In this article we review the steps to germinate cannabis seeds, tips and tricks in the process, and how to keep your seedling healthy.
Germinating a seed is the first step in the growing process, and a cannabis seed will sprout with a voracious hunger, so if you are about to germinate seeds, start thinking ahead about where the seedling will eventually be moved to. This includes lighting, ventilation, and something to feed the lady. Those things don’t need to be decided before you begin, but try to have a plan in place by the time the second set of leaves emerges — as soon as two weeks.
The Germination Process
Begin by soaking the seed overnight. Soaking the seed saturates it with moisture, and moving it shortly after to a warm home tells the seed that it’s someplace comfortable, and it’s time to grow. Tap water is fine for this, but a micronutrient solution like liquid seaweed may be included.
Once your seed has soaked, the most common method for germination is the “paper towel method.” Wet a piece of paper towel and wring dry, then fold in half. Place the seeds between the halves of the damp paper towel, and slide the whole thing into a ziplock bag. Seal with some air inside. Leave this bag someplace comfortably warm for about a week, checking frequently for spots of mold. After about a week, a taproot should emerge.
Then it is time to transfer the seed into a proper growing medium. Be careful plucking your seed from the paper towel!
A grow medium is the “stuff” the seed will sit in. The easiest option is soil, healthy black earthy scooped up from your yard, or potting soil purchased from any garden center. Rock wool cubes are a common option for hydroponic growers, but can later be transplanted into soil as well. Compost and worm castings are great for a seedling, but it will need to be transplanted into a more diverse mixture later.
It is far too early to begin any nutrient cycle, or to introduce any fertilizers to the soil. Now that the seed is confirmed as alive, and placed into a more comfortable medium, simply make sure that the seed is watered and warm.
The first set of leaves to emerge are called “sucker leaves,” and their sole purpose is to drink in as much light as possible to fuel the growth of the more recognizable serrated leaves, which will begin to grow over the next week. After that you’ve got a proper seedling, and in a few weeks it will be ready for a bigger home!
For further guidance and resources about growing cannabis, see our Beginner’s Guide to Growing Marijuana, or our guide to growing for personal use.
Cultivating a Healthy Cannabis Seedling
The seedling that emerges will be as tender as an infant, and susceptible to diseases and cross-contaminations, so keep your germination station as sanitary as possible, and wash your hands before handling them. Avoid rubber or latex gloves at this stage as they have too much grip, and one wrong movement of your finger could accidentally grab and tear the soft plant material.
A seed’s health may be fortified by soaking it with a solution rich in micronutrients, like liquid seaweed. Be advised, however, that these will be very diluted solutions. Carefully read the mixing instructions of any product you purchase.
Seedlings can be protected against certain diseases by including worm castings in the medium. Research out of Cornell University has shown the microbial life in worm castings colonizes the seed’s surface, making it more difficult for pathogenic microbes to establish themselves.
Disclaimers and Downsides Regarding Found Seeds
It’s worth pausing to remember that seeds shouldn’t wind up in your bag of cured, smokable cannabis. So before planting anything, let’s assess what this seed is, and how it got there.
Only female cannabis plants produce flowers, and if they are pollinated by male plants, then they produce seeds instead. So all the cannabis we smoke is from unpollinated female plants — or nearly all of it.
When female plants are stressed — for instance, by drought conditions or nutrient problems — an evolutionary alarm can induce them to produce seeds with only their DNA. The problem with these “hermaphrodite seeds” is that the offspring, having benefited from this process, will be more prone to repeat it. If this is how a seed got in your bag, it can result in seedy weed, even under the closest care.
A seed is not guaranteed to sprout at all. Examine the seed for any obvious health issues. Immature seeds are lighter greys-to-green, while mature seeds are darker tan, brown, or even black. A healthy shape is a teardrop or nearly round, while bunk seeds will appear shrivelled or irregular. Finally, healthy seeds have a hard, whole shell, while cracked or brittle shells will likely not sprout, or produce a less healthy seedling.
A found seed is also not a guarantee to produce a replica of the strain you smoked, and may present latent traits from the strains it was bred from. Cultivating a complete copy of a phenotype is called “cloning,” and the cloning process must begin with a living plant, not a seed.
Remember, it could also just result in a male plant, which won’t grow any buds. None of this is guaranteed to happen with a bag seed, it’s just more likely than with a stabilized seed from a producer.
If you want to germinate a seed you’ve found, begin by soaking it overnight in water to saturate it, and soften the shell. Micronutrient solutions can be mixed in at this stage to fortify the health of the seedling (if you do, be sure to read the mixing instructions on the label).
The “paper towel method” is the most accessible way of germinating almost any seed. Once a taproot has emerged (after about a week) plant the seed into a small container with your chosen grow medium, like soil. Do not fertilize at this stage, as the seed and resulting seedling are very tender, and concentrated fertilizers are abrasive chemicals. Within another week, “sucker leaves” will sprout, synthesizing light to produce further growth.
Remember, found seeds are not always healthy or even viable. A healthy seed has a hard, unbroken shell and a dark color, while brittle or misshapen seeds may not produce a healthy plant, if anything at all. A found seed is also not guaranteed to replicate the precise phenotype of that cannabis you found it in.
That said, it’s almost always worth trying, and experimenting with whatever results. Growing cannabis can be an enriching experience, and perhaps even save you some riches. As long as you know what to look for from a seed, and how to handle them, finding one in your bag could be a golden ticket.