How to produce cannabis seeds
When it comes to cannabis plants, feminized seeds are the most known ones. But do you know what auto and regular means?
1. Photoperiodic Cannabis
Photoperiodism isn’t unique to cannabis plants, many flowering plants sense changes in the length of night and day and use those changes as signals for when to flower. Photoperiodic cannabis plants are just like that, they basically respond to changes in the light cycle. As the night becomes longer at the beginning of autumn (in nature) or when you flip to 12/12 in a grow tent, the plant receives more darkness. This causes the plant to realize that its life cycle is coming to an end and they will start to flower (females) or produce pollen (males) in order to reproduce before winter.
Regular Photoperiodic Cannabis
Regular cannabis is photoperiodic cannabis that produces both male and female plants. They are called regular because they are produced the “natural way”: the pollen from the male plant pollinates the female, resulting in seeds. Back in the day, the only way to grow cannabis was with regular seeds, this way you would get half male and half females plants. There is a big difference between male and female plants, while female grows buds, male plants will only grow pollen sacs.
In nature male cannabis’ pollen sacs will open to release pollen which will pollinate the female flowers, this way producing seeds. But most growers that grow cannabis commercially or for their own consumption only want buds, allowing males to pollinate buds would ruin their harvest because pollination diminishes yield, so they’re mainly looking for female plants.
Feminized Photoperiodic Cannabis
To completely avoid accidental pollination and other problems related to male plants, feminized seeds were created. Feminized seeds come from the cross of two female plants, one of them is stressed so it starts producing pollen sacs, which will fertilize the other female. When you cultivate feminized seeds, the offspring will be only female plants. This takes out a lot of the unnecessary work that you can have when growing males and them not being able to use them. Ever since the boom of feminized seeds back in 1998, growers have stopped buying regular seeds for quite a bit. Nowadays most seed banks don’t even sell regular seeds anymore. With so much focus on feminized seeds, we can’t forget that regular seeds are vital for the creation of new strains.
2. Automatic Flowering Cannabis
You must already know that the characteristic that makes autoflowers an auto is they don’t need a different light cycle to enter the flowering stage. Like their name says, autoflowers start flowering automatically depending on age, and unlike regular and feminized cannabis that needs a change in the light cycle to start flowering. Autos don’t need anything else other than time to start producing buds.
But that trait didn’t come out of anywhere, it appeared as an adaptation to the environment. You’ve probably heard of Cannabis Indica and Sativa…well, the autoflowering gene comes from Cannabis Ruderalis. The Ruderalis species adapted to the extremely cold and harsh climates of Asia, Europe, and Russia. These regions have shorter warm seasons and colder temperatures. Because of this, Ruderalis started mutating from a photoperiodic plant to an autoflowering plant, to guarantee its reproduction before the temperatures reached freezing levels. Thanks to that adaptation, now we have autoflowers that take considerably less time from seed to harvest.
3. How To Make Your Own Seeds
Producing your own seeds is relatively easy if you have what it’s needed but that doesn’t mean the result will be a perfect strain. The good strains or “IBLs” that most seed banks sell are strains that have been developed for years and are far into the third or fourth generation. IBL or stabilized strain means the offspring will have certain characteristics locked down. When you cross two strains for the first time the offspring can have infinite phenotypes and this is not good for commercializing.
Photoperiodic Regular Seeds
When we talk about cannabis, it’s easy to forget about male plants. Everybody nowadays is used to the beautiful flowers we all love, but it’s important to remember that male cannabis plants are just as important as females. Male cannabis plants produce pollen and are an essential element in the production of new cannabis plants. This pollen is super important in breeding cannabis as it allows breeders to create crosses with genetics from different plants and create their own seeds. For producing seeds all you need is pollen and buds. Cannabis pollen is no different from regular pollen produced by other plants. It’s a fine powder that usually has a golden yellow color and is excreted from the pollen sac on male plants.
Collecting pollen is simple. You’ll know when its ready to be collected when the pollen sacks are open and you see pollen floating in the air and on the leaves near them. When this happens, you can gently remove the sacs and store them in a ziplock bag, once you are ready to pollinate just release the pollen onto the buds. Another way is to simply agitate your male plants near the female plants, the pollen will stick to the buds. Pollen is used in order to pollinate female plants and create seeds. In nature, female plants get pollinated by the wind which carries the male pollen. Cannabis seeds develop in the buds about 4-6 weeks after pollination, you will see the calyxes start to round up from the seeds being inside them.
Pollinated buds look quite different from regular buds. They usually don’t have as many trichomes and are usually smaller and a lot more swollen. 4 weeks after pollination, you can start checking the buds to see if the seeds are ready for harvest by picking a couple of seeds from the bud. Mature seeds will have a hard shell and be a dark brown color, they might also have some stripes on the outer shell.
Photoperiodic Feminized Seeds
Normally, a male cannabis plant has to pollinate a female plant to produce seeds. The resulting regular seeds will contain about half male and half female seeds. The way feminized seeds are produced is the same but instead of collecting the pollen from a male, breeders will stress or spray flowers with colloidal silver, for example. This process forces the female plants to become a hermaphrodite and starts producing pollen sacs. Hermaphrodite plants are females that are halfway turned into males, this means she has both male (pollen sacs) and female (buds) parts.
By picking out the pollen sacs and using a reverted plant’s pollen to pollinate a female plant, you will have only female genes as there is no “father”, this way you get feminized seeds, meaning the offspring will be 100% female plants.
Feminized and Regular Autoflowering Seeds
Regular Autoflowering Seeds
Usually, you can find regular and feminized seeds, and this applies to autoflowering seeds also. This means you can find male and female autoflowers, depending on the type of seed you buy (regular = 50% male and 50% female, feminized = 100% female). Unfortunately the high increase in the production of feminized seeds affected automatic seeds also. Although it’s not common to find regular auto seeds nowadays, they do exist. For producing regular autoflowering seeds all you need is male pollen and female buds, just like for regular photoperiodic cannabis. The process is basically the same, collect the pollen from the male and spread it on the buds, this will result in regular autoflowering seeds.
Feminized Autoflowering Seeds
The process of producing feminized autoflowering seeds is almost the same, the only difference is you will need two female autos instead of one male and one female. You will have to make one of your female autos produce pollen, either by stressing her out or spraying with colloidal silver and pollinating the other female. This will result in a 100% female automatic offspring.
4. Pollen Collection and Storage, and Proper Pollination Techniques
The process of collecting pollen from either a male or a hermaphrodite cannabis plant is a piece of cake, but you do have to be very careful if you have female plants nearby. One male or hermie plant can pollinate a whole crop if you are not alert and aware of the stage the pollen sacks are at, so always try to keep any pollen-producing plants well quarantined from any females that you want to keep seed free. The best way to harvest the pollen is to carefully remove the whole pollen sac flower head, let it dry for a couple of days to a week and then transfer the whole shebang to a sealable container or zip-lock bag. Once in the bag or container, you can give the whole thing a bit of a shake and the pollen should fall right out In terms of pollen storage, there are a few factors to take into consideration. Temperature and moisture levels are the most important things to control. Our tried and true method for at-home storage of cannabis pollen is:
- Collect the pollen and place it in a sealed container or zip lock bag.
- Add regular baking flour – about double the weight of pollen. This doesn’t need to be super exact, but it helps greatly with moisture absorption and spreads your pollen out much further.
- Place the whole thing into the freezer where it can be stored for up to a year.
- Pollen hates temp fluctuations, so leave it be until you are sure you are ready to use it
When you are ready to pollinate your plant the process is again nothing more than child’s play, but you have to be very careful not to spread the pollen to plants that you want to remain seedless. This can be a little difficult if the plants are rooted into the ground, but if they are in pots then the job is much safer.
Just move whichever female plant you want to produce seeds to an area well away from the rest of the crop. There are a few ways to pollinate your plant, but our favorite method is this:
- Wait until the female plant is in her 2nd or 3rd week of the flowering cycle. At this point, you should see pistils forming fully (the small white hair-like growths)
- Grab your pre-collected pollen from the freezer and let it come to room temp over a few hours
- Dip a small, fine paintbrush or Q-tip into the pollen and apply it to the pistils of the budding sites that you want to produce seeds
- We recommend focusing on the budding sites on the lower branches – the popcorn bud producing areas. These buds are usually the lowest quality in terms of smokeability and trichome production, so use these ones for seeds instead!
- Seeds usually take around 4 – 5 weeks to mature fully. A mature cannabis seed is brown in color with tiger-like stripes and a hard outer shell.
A common question asked is – how many seeds a single budding site will produce? This is an impossible question to answer, as it varies widely between strains and the size of the budding site. But a fully pollinated plant can produce A LOT of seeds.
5. In Conclusion
Even though it is fairly easy to produce seeds, we recommend having a bit of experience before trying it. We recommend easy-to-grow strains like Zkittlez Auto to start acquiring experience before going into breeding.
Just an easy to grow, solid packed buds. A heavy feeder and can be a bit prone to light burn at the end but otherwise perfection!
A breeding operation needs a lot of caution, even the smallest amount of pollen may ruin your entire harvest. Remember you should always buy seeds from a reputable seed bank. If you buy bad genetics, your plants can become a hermaphrodite easily and what was initially cheap can end up being surprisingly expensive.
Marijuana Cultivation/Producing Seeds
Sooner or later every grower is going to want to produce marijuana seeds. Developing a new stable strain is beyond the scope of this discussion and requires the ability to grow hundreds or even thousands of breeding plants. However, just about any grower can manage to preserve some genetics by growing f2 seeds where they have crossed a male and female of the same strain, or can produce a simple cross which would be referred to as strain1xstrain2 for instance white widow crossed with ak-47 would be referred to as a WW x AK-47. You can produce some excellent seed and excellent marijuana this way.
To Feminise or not to Feminise Edit
There are numerous myths surrounding feminized seeds. Feminizing seeds are a bit more work than simply crossing two plants naturally. However it will save you a lot of time in the end. If you make fem seeds properly then there is no increased chance of hermaphrodites and all seeds will be female. This means no wasted time and effort growing males and it means that all your viable seeds produce useful plants. Since roughly half of normal seeds are male this effectively doubles the number of seeds you have.
Feminized seeds are bred to contain no male chromosomes, which will be able to produce the crop of resinous buds sought by most growers. For gardeners who require a quick and easy cultivation process, feminized seeds are the ideal choice. Some medicinal cannabis users may be deterred from growing their own supply because of the perceived difficulty of growing or of identifying the different genders and removing males early in the blooming period. Feminized seed-strains offer a simple solution to these issues, as there is no need to spend time in the first weeks of flowering checking for male plants.
Other times you will have no choice but to produce feminized seed because it will be a female plants genetics that you want to preserve and you won’t have any males. Perhaps you received these genetics via clone or didn’t keep males.
The new thing on the market for commercial Cannabis cultivation are auto-flowering feminized strains. By crossing of the cannabis ruderalis with Sativa and Indica strains many cultivators have created interesting hybrids which boast benefits from both sides of these families.
The first ‘auto-flowering cannabis seed’ which came on the market a few years ago was the Lowryder #1. This was a hybrid between a Cannabis ruderalis, a William’s Wonder and a Northern Lights #2. This strain was marketed by ‘The Joint Doctor’ and was honestly speaking not very impressive. The genetics of the ruderalis was still highly present which caused for a very low yield and little psychoactive effect. Not very attractive.
Auto-flowering cannabis and the easily distributed seed have opened a whole new market in the world of the online grow-shop, making it easy for home growers with shortage of space to grow rewarding cannabis plants in many different varieties. To grow plants indoors, a growing medium (e.g. soil or growing Potting soil, irrigation (water), fertilizer (nutrients), light and atmosphere need to be supplied to the plant.
Auto-flowers have been rising in popularity fast and there are now auto flower growers communities. These Web properties allow users to get information on how to grow these non photo-sensitive plants and what are the best practices when producing and germinating auto-flower seeds.
Selecting Suitable Parents Edit
There are a number of important characteristics when selecting parents. First are you making fem seeds? If you are then both parents will be female. This makes things easier. If not then the best you can do is select a male with characteristics in common with the females you hope to achieve from the seed.
Obviously potency, yield, and psychoactive effects are critical to the selection process. But some other important traits are size, odor, taste, resistance to mold and contaminants, early finishing and consistency.
Collecting and Storing Pollen Edit
In order to collect pollen you simply put down newspaper around the base of the plant. The pollen will fall from the plant onto the newspaper. You can then put this newspaper into a plastic bag and store it in the refrigerator or freeze it. Pollen will keep for a few months in the refrigerator and can be used on the next crop. Filtering the pollen through a silkscreen, drying, and freezing can extend viability for decades. At least one reader indicates success using pollen treated in this manner and stored at -30 c for 17 years. The chance of viability does decrease with time, even in the freezer, so the more fresh the pollen the better. Wrapping the pollen in a layer of aluminum foil and then a layer of plastic should help to protect it from freezer burn. Additionally, oxygen evacuation such as with a heavy gas like nitrogen or vacuum sealing should provide additional assurance of preservation.
Pollinating a Plant Edit
To pollinate a plant you can brush the pollen on a flower with a cotton swab or you can take the plastic bag, then wrap the flower inside it and shake, trapping the pollen inside for easier transportation. In this way you can selectively pollinate plants and even individual buds and branches.
Male Isolation Edit
A male plant or a plant with male flowers will pollinate your entire crop rendering it seedy. You probably don’t want THAT many seeds so how can you avoid it? Moving the male to another room might work but if that other room shares an air path via ducting or air conditioning then pollen may still find its way. One technique is to construct a male isolation chamber.
A male isolation chamber is simply a transparent container such as a large plastic storage tub turned on its side (available at your local megamart). Get a good sized PC fan that can be powered with pretty much any 12v wall adapter, by splicing together the + (yellow or red on fan, usually dotted on power adapter) and the – wires (black on fan, usually dotted power adapter) just twist with the like wire on the other device and then seal up the connection with electric tape. Then take a filtrate filter and cut out squares that fit the back of the pc fan so that the fan pulls (rather than pushes) air through the filter. Tape several layers of filter to the back of the pc fan so all the air goes through the filter. Now cut a large hole in the top of the plastic container and mount the pc fan over top of it so it pulls air out the box. You can use silicon sealant, latex, whatever you’ve got that gives a good tight seal.
This can be used as is, or you can cut a small intake in the bottom to improve airflow. Pollen won’t be able to escape the intake as long as the fan is moving but you might put filter paper over the intake to protect against fan failures. You can also use grommets to seal holes and run tubing into the chamber in order to water hydroponically from a reservoir outside the chamber. Otherwise you will need to remove the whole chamber to a safe location in order to water the plant or maintain a reservoir kept inside the chamber.
Making Feminized Seed Edit
To make feminized seed you must induce male flowers in a female plant. There is all sorts of information on the Internet about doing this with light stress (light interruptions during flowering) and other forms of stress. The best of the stress techniques is to simply keep the plant in the flowering stage well past ripeness and it will produce a flower (with seed).
Stress techniques will work but whatever genetic weakness caused the plants to produce a male flower under stress will be carried on to the seeds. This means the resulting seeds have a known tendency to produce hermaphrodites. Fortunately, environmental stress is not the only way to produce male flowers in a female plant.
The ideal way to produce feminized seed through hormonal alteration of the plant. By adding or inhibiting plant hormones you can cause the plant to produce male flowers. Because you did not select a plant that produces male flowers under stress there is no genetic predisposition to hermaphroditism in the seed vs plants bred between a male and female parent. There are actually a few ways to do this, the easiest I will list here.
Colloidal Silver (CS) Edit
This is the least expensive and most privacy conscious way to produce fem seed. CS has gotten a bad name because there is so much bad information spread around about its production and concentrations. It doesn’t help that there are those who believe in drinking low concentration colloidal silver for good health and there is information mixed in about how to produce that low concentration food grade product. Follow the information here and you will consistently produce effective CS and know how to apply it to get consistent results.
Simply construct a generator using a 9-12 v power supply (DC output, if it says AC then its no good) that can deliver at least 250ma (most wall wart type power supplies work, batteries are not recommended since their output varies over time). The supply will have a positive and negative lead, attach silver to each lead (contrary to Internet rumors, you aren’t drinking this so cheap 925(92.5%) Stirling silver is more than pure enough. You can expose the leads by clipping off the round plug at the end and splitting the wires, one will be positive and the other negative just like any old battery. Submerge both leads about 2-3 inches apart in a glass of distilled water (roughly 8 oz). Let this run for 8-24 hrs (until the liquid reads 12-15 ppm) and when you return the liquid will be a purple or silver hue and there may be some precipitate on the bottom.
This liquid is called colloidal silver. It is nothing more or less than fine particles of silver suspended in water so it is a completely natural solution. It is safe to handle without any special precautions. [ citation needed ] The silver inhibits female flowering hormones in cannabis and so the result is that male flowering hormone dominates and male flowers are produced.
To use the silver, spray on a plant or branch three days prior to switching the lights to 12/12 and continue spraying every three days until you see the first male flowers. Repeated applications after the first flowers appear may result in more male flowers and therefore more pollen. As the plant matures it will produce pollen that can be collected and used to pollinate any female flower (including flowers on the same plant).
Silver Thiosulfate (STS) Edit
Silver Thiosulfate is a substance that has similar principle, application and results of CS, but is more difficult to make. STS is more difficult to acquire, but it can still be obtained directly from a chemical supply company. STS is not an expensive or controlled substance.
Gibberellic Acid (GA3) Edit
This is probably the most popular way to produce feminized seed, but at the same time the least effective. GA3 is a plant hormone that also causes the plant to stretch uncontrollably. It can be purchased readily in powdered form, a quick search reveals numerous sources on e-bay for as little as $15. Simply add to water to reach 100ppm concentration and spray the plant daily for 10 days during flowering and male flowers will be produced.
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.