Cannabis seeds are ready to plant and grow once they successfully germinate or once the root has broken through the protective outer shell of the seed. Cannabis seeds are available in regular, feminized, and auto-flowering forms. Home growers of cannabis often choose feminized seeds to ensure that the adult plant will be a flowering female.
Cannabis seeds are brown and about the size of a peppercorn. Photo by: Gina Coleman/Weedmaps
More about marijuana seeds
As with all angiosperms, or flowering plants, cannabis produces seeds that contain all of the genetic information needed for growth and reproduction. When a seed is planted, the translation of this genetic material dictates each unique physical characteristic the mature plant will have. If these are desirable traits, like potency, smell, vigor, etc., a breeder can select for these through a long process of genetic stabilization through generations, which eventually leads to the creation of a cultivar, or strain.
Anatomy of a cannabis seed
Cannabis seeds are about the size of a peppercorn, ovular in form, and pointed on each end with a ridge that transverses longitudinally on only one side from tip to tip. It is this ridge that opens up during germination. The opposite side is rounded. The body of the seed is brown, but underdeveloped and unfertilized seeds can have an off-white color and are typically smaller in size.
Photo by: Illustration by Weedmaps
The body of a marijuana seed is spotted or striped, most commonly with light brown specks, but some varieties of cannabis can have red or yellow markings. Plant embryos are contained within seeds and house all cells that will eventually differentiate into leaves, roots, and stems. Embryos, found within the reproductive organs, are protected by an outer envelope called the pericarp. Crucial components of the plant embryo are the cotyledons, the first leaves to appear from the seed, and the radicle, which develops into the primary root. Once the seed germinates and begins its growth into a mature plant, special structures called root caps protect the growing tips of the plant.
Today’s commercially cultivated cannabis does not contain seeds. The cultivation practices that have made this widespread are rooted in fundamental biological concepts. Cannabis is a dioecious plant, meaning it has separate male and female organisms, just like humans. If a female plant matures in the presence of a male plant, pollen from the male will fertilize the female, and its bracts will contain seeds at the end of the flowering cycle. Seedless cannabis is commonplace even when it originates from mass-produced outdoor cultivation, but not too long ago, this was not the case.
Around the middle of the 20th century, growers discovered that culling male plants as soon as they display their sexed traits would result in a crop containing exclusively unfertilized females, yielding cannabis flowers higher in THC that don’t require the removal of seeds before smoking. This seedless cannabis was from then on dubbed sinsemilla, which translates to “without seed” in Spanish. It is also commonly spelled sensimilla.
How cannabis seeds are produced
Commercial growers who produce cannabis flower desire seedless plants but there are also cultivators interested in selling seed to the growing home-cultivation market. Cannabis seed production begins with the pollen grain of a male plant. From this grain, a pollen tube grows, producing male generative cells that disperse in the form of pollen. The migration of pollen into a female plant ovule triggers pistils to fall off and seed production to begin. The bracts, which contain the ovule, will then fill with seeds. Since seeded plants are a natural outcome of pollen fertilizing eggs, producing cannabis seeds is a matter of letting nature take its course.
What’s the difference between feminized, regular, and autoflower seeds?
There are a few differences to note between these cannabis seed types.
- Feminized seeds: The key difference between feminized cannabis seeds and regular cannabis seeds is that feminized seeds have been engineered to produce exclusively female plants. This matters for cultivation since smokable flowers are produced only by female plants. A male plant can potentially ruin a harvest if it pollinates nearby female plants, causing them to produce flowers full of seeds.
- Autoflowering seeds: Autoflowering seeds have been carefully bred to begin and complete the flowering process based on the plant’s maturity rather than how much light the plant receives each day. Autoflowering seeds tend to be simpler to grow and don’t require as much light, making them perfect for places where the growing season is short or for indoor grows.
Is it illegal to buy marijuana seeds?
Marijuana seeds are a cannabis product, so if you live in a place where cannabis is illegal, then seeds are also illegal. However, some people who live in places where weed is not yet legal purchase marijuana seeds from marijuana seed banks as a “souvenir.” Either way, if you want to buy marijuana seeds and cannabis is illegal where you live, then you face some degree of risk. On the other hand, if you live in a state where cannabis is legal, especially one where home cultivation is allowed, then you should be able to purchase seeds legally. Remember, even in states where cannabis is legal, it’s still illegal nationally in the US. To cut your risk as much as possible, purchase cannabis seeds from in-state or local providers so they don’t have to cross state lines or be transported by mail.
Where to buy marijuana seeds
Seeds are sold in brick-and-mortar locations legally in many countries across Europe and are often traded online. As cannabis legalization expands in North America, more retail locations are carrying seeds as well. Feminized seeds are the most popular, but providers likely have access to many strains of mixed male and female seeds. Carefully sifting through cannabis flower before using the grinder will usually turn up a few seeds, too. Professionally sourced seeds assure quality genetics and viability, but saved seeds can be a cheap source of cannabis genetics for the hobbyist grower.
Do dispensaries sell seeds?
If you live in a state or country where cannabis is legal, and where individuals are allowed to grow their own plants at home, then you should be able to buy seeds at most legal dispensaries. This might not be the case if you’re in a location that does not allow home growing. The best thing to do is simply check your local laws and ask your local budtender.
How much do marijuana seeds cost?
A pack of marijuana seeds—typically containing around ten or so seeds—will run you anywhere from around $40 on the low end and as much as $400 or $500 on the upper end. The price of marijuana seeds depends on a number of variables including:
- Quality of genetics
- The reputation of the breeder who produced the seeds
- How rare or potent the strain is
- Whether they’re regular, feminized, or autoflowering (feminized and autoflowering marijuana seeds tend to cost more)
How many seeds should I buy?
If you’re trying to grow just a handful of plants for your own private consumption, then you can get away with purchasing one or two packs at a time. Since most commercially sold marijuana seeds come in packages of 10 or so seeds, 10 to 20 seeds should be enough to ensure a good harvest even if a few seeds fail. This is a baseline for a small, private crop andany larger operations should scale up accordingly.
How to store cannabis seeds
Seed providers sometimes vacuum-seal and freeze seeds for long-term storage, but commercially-available seeds in Dutch headshops are sold in small, plastic vials at room temperature and low humidity (6-12%).
Humidity and light is the main enemy of seed storage. Beyond that, seeds can remain viable for up to two years when stored in even the most haphazard conditions. Marijuana seeds swept up off the floor or found in the bottom of a drawer have been known to grow into vigorous young plants.
Germinating cannabis seeds
Germination is the process of beginning the vegetative growth of the new cannabis plant. Sometimes referred to colloquially as “popping,” this process starts when the seed is exposed to water and light. The seed abandons its state of dormancy, or quiescence, and resumes essential metabolic processes that feed on energy stores to delicately rupture open the shell and grow its first root. This root will elongate until it has taken hold of the medium, after which it will pull two small embryonic leaves (cotyledons) from the seed shell. Cotyledons are in the seed before germination and are not considered “true” leaves. The cotyledons will grow until they are about one centimeter long, and once the stem below this is around five centimeters tall, another set up true leaves will grow out of the top and the stem between the true leaves and cotyledons will continue to elongate.
Photo by: Gina Coleman/Weedmaps
Generally speaking, cannabis is a hardy plant that will grow and even thrive in a diversity of environments. However, to assure germination, several steps can be taken. One method calls for a moist paper towel inserted into a plastic bag. Once the first root appears, the seedling must be carefully transferred to some soil before the root takes hold to the paper towel.
Cannabis seeds can also be germinated in a peat pellet. Plant the seed only just below the surface. Once the seedling has taken hold in the pellet, directly transfer it to a pot; the roots will grow right through the soft fabric that encases the peat, at which point the pellet can be directly placed into soil. Whichever method is used, keep the temperature between 70 -90 degrees Fahrenheit (21-32 degrees Celsius), ideally at 78 degrees Fahrenheit (about 26 degrees Celsius), keeping seedlings covered to maintain humidity. Seedlings and young cuttings require photosynthetically active radiation that is more heavily weighted in the blue portion spectrum; a common fluorescent desk lamp will suffice until they are about 5 inches, or about 13 centimeters, tall.
Where Are Marijuana Seeds On The Plant?
Where are Marijuana seeds on the plant. In the flower of course
If you are wondering where are Marijuana seeds on the plant, you are not alone. After a female plant gets pollinated by a male plant, you will be able to find marijuana seeds in the flowers after a few weeks. Ideally, you should let the flowers mature completely so that you are able to find marijuana seeds that were on the plant but fell off the flower. These Marijuana seeds are completely mature and can be used, although you won’t be able to know if they are male or female until the plants have been grown out.
Normally when a marijuana plant gets seeds, the potency of the flower will be reduced by up to 30%.
You could also find our FAQ Submission How Many Marijuana Seeds To Grow A Plant? useful
How to Grow Marijuana from Seed
If you’re in a location where cannabis (another term for marijuana; short for the plant cannabis sativa) is illegal, growing it is probably illegal too. Bringing in seeds or cuttings to your location can very well be a felony, and reputable sellers won’t ship to you.
You can probably purchase and grow hemp seeds and plants, which have a negligible amount of THC, but these plants won’t produce the psychoactive effects of plants that contain higher levels of THC. Check with your seller to be certain you’re getting what you think you’re purchasing. If you buy seeds for CBD-only hemp plants by mistake, you can end up being very disappointed post-harvest.
How to acquire seeds or cuttings
You can usually find cannabis seeds for sale at most dispensaries in areas where growing cannabis for personal use is legal. You may also find growers who sell cuttings/clones. You can expect to pay $50 to $100 for a pack of ten seeds. When shopping for seeds or cuttings, read the labels and any other information the manufacturer provides on its website or in its catalog to make sure you’re getting the right seeds or cuttings (the strain) for the plants you want to grow.
One way to get your mitts on some seeds is to collect seeds when you find them in flowers you purchased, or get some from friends if they’re collecting.
- Feminized seeds: Nearly all seeds sold by reputable companies are feminized, but make sure they are. These seeds are specially treated to grow into female plants.
- Auto-flowering or photoperiod: Auto-flowering plants are easier, because they enter the flower stage after a certain number of weeks regardless of the light/dark cycle. If you’re a beginner, seriously consider going with auto-flowering plants.
- Genetic background: If seeds are from a well-established strain, such as O.G. Kush, Bubble Gum, or a cross-breed, the genetic background should be stated.
- Blend: The blend represents the percentage of the three species — sativa, indica, and ruderalis. All auto-flower strains contain some percentage of ruderalis, which is responsible for the auto-flowering nature of the plant.
- Yield indoors: The number of grams of bud per square meter of plant when grown indoors.
- Yield outdoors: The number of grams of bud per plant (after drying) when grown outdoors.
- Plant height indoors: Shorter than when grown outdoors.
- Plant height outdoors: Taller than when grown indoors.
- Time to harvest: Approximate number of weeks after germination the flower should be ready to harvest.
- Potency: Percentages of CBD and THC.
- Effect: The type of experience you can expect when consuming product from the plant.
Know the laws about buying cannabis
- In some European countries, laws prohibit growing cannabis, but seed is legal, which is quite confusing. You’re allowed to buy and eat cannabis seeds because they’re non-psychotropic, but you can’t buy them to grow cannabis. Other countries in Europe, such as Germany, have their own seed laws.
- In Canada, where cannabis is federally legal, seeds can be shipped across provincial lines.
- In the U.S., in some states in which cannabis is legal, you can purchase seeds from some dispensaries or other locations to grow plants as long as you keep them in the state. Other states may bar selling to non-licensed growers. Shipping or transporting seeds across state or international borders is illegal, although a few reputable online seed stores ship to individuals with success.
Cuttings are typically treated in a similar manner as seeds in legalized locations. They may be available from some dispensaries or outlets for pick up or delivery with a fee. They’re prohibited from crossing U.S. state lines or international borders. You can buy individual plants and mix and match strains. Prices vary and are often determined by plant size.
Buy cuttings (clones) only from a reputable source who understands proper back-crossing of strains for stability. Back-crossing involves pollinating a plant with one of its parent plants to promote sexual stability, so that when you have a female it won’t hermaphrodite into a male during flowering.
Both seeds and clones are often able to be purchased from commercial locations already in your state.
In the U.S., transporting any part of the cannabis plant over state lines is illegal. This applies to seeds and clones and, technically, even to tissue samples.
How to germinate cannabis seeds
Germinating seeds requires a dark environment that is around 70 degrees. There are many ways to germinate seeds (in soil, in a wet paper towel, in starter plugs) You can also sow them directly into soil in a garden or container, as long as the soil is light and fluffy, so the roots can easily grow down and the stalk can break through the soil. Plant the seeds about 1/4- to 1/2-inch deep and cover them loosely with soil.
Most importantly, seeds need a moist environment; they won’t germinate if they get too dry. You can use a heat mat to increase the success of germination in colder climates.
How to transplant marijuana plants
When transplanting any plant, whether it started from seed or a clone, handle it gently, being very careful not to damage the roots. Center the plant in the pot, and plant it deep enough to cover the root ball completely in soil. If the plant is root bound, you can gently tease the roots apart to encourage outward growth.
Pack your soil or other grow medium down around the roots well enough to support the plant while new roots grow, but not so tight that the soil restricts outward root growth. Water the soil around the roots.
About This Article
This article is from the book:
About the book authors:
Kim Ronkin Casey has been a communications professional for more than 20 years and recently took a year-long leap into the world of cannabis as the communications manager for one of the leading dispensaries in North America. She now consults for companies in the industry on internal and external communications. Joe Kraynak is a professional writer who has contributed to numerous For Dummies books.