Germinating cannabis seeds is important because it gives the grower an advantage in cultivation and it speeds up the process Jorge Cervantes, veteran marijuana cultivator and author of “The Cannabis Encyclopedia” shares his process for germinating cannabis seeds into healthy sprouts. Learning how to germinate cannabis seeds is essential to all future growing success. Properly popping beans puts you on the road to healthy plants and heavy harvests. But there are a few things to consider in order to master how to germinate cannabis seeds the right way.
How to germinate all types of cannabis seeds: Three methods
A seed is like an egg in many ways. Inside are very similar components: an embryo, a radicle, a plumule and cotyledons, and outside is a protective shell.
Germination is important because it gives the grower an advantage in cultivation and a faster start. And it makes sure you’re not planting a small rock where nothing will grow out of the ground.
The different types of cannabis seeds
For those who want to cultivate for recreational or medicinal purposes, the female plant is the only one that matters. Only she can produce the flowers we expect at the end of the cycle.
Cannabis is a dioecious plant, that is, it has a female and a male plant. The male flower produces pollen after calyx development, which, when it meets the flowers and pistils of a female plant, will be fertilized, generate a new seed, and guarantee the survival of the species.
Cannabis seeds have undergone several modifications and are currently available in three main categories: normal, feminized, and auto-flowering, also called automatic. Recently, a new category, quick flowering seeds, has gained popularity.
Regular or normal seeds
Regular seeds are mostly chosen by breeders and established growers seeking stable genetics. (Algirdas Gelazius/123rf)
If the cultivator’s desire is to perpetuate a variety or make improvements, he should choose seeds of the normal or regular type. They are created by crossing a male with a female plant.
We call them regular or normal because they develop naturally. This type of seed can produce species of both sexes. Here, the grower has no control over gender. The odds are divided. Regular seeds have a 50% chance of being a female plant and generating flowers, or 50% of being male, which will result in small bags which grow very quickly into clusters of calyxes and flowers with pollen grains, essential for the multiplication of the species.
Regular seeds are mostly chosen by breeders and established growers seeking stable genetics or new cannabis terpenes or profiles by pheno-hunting through regular seeds which become the mother stock for all feminized seeds. Traditional landrace growers continue a long tradition of growing flowers and pollinating their crops which lose commercial value but guarantee sufficient seeds for the next season. Traditional landrace growers are slowly disappearing from the most remote regions on earth due to feminized seeds and readily available hybrids seeds which fetch a higher commercial value.
- Breed and create new strains
- Equal probability of male and female plants
- Create pollen bank
- Sex of the plant is unpredictable
- Male and female plants can be confused by a novice grower
- Pollinating males will seed female plants, resulting in fewer flowers to be harvested by the grower
- Preparation of different grow tents
Feminized seeds are obtained by crossing two female plants. One of them is exposed to a high level of stress. (Shutterstock)
In the late 1990s, with the need to cultivate seeds that guaranteed the appearance of female plants, feminized seeds emerged. As the name implies, they are those that will result in female plants. Males are unlikely to appear unless cannabis is under stress or someone has offered it a “cat for a hare.”
In the beginning, these plants had quality problems or were genetically unstable. Furthermore, they could transform into hermaphrodite plants. Over the years, with improvements and new technologies, feminized seeds have achieved high levels of quality both in production and in taste and final effects.
Feminized seeds are obtained by crossing two female plants. One of them is exposed to a high level of stress until it becomes a hermaphrodite. After crossing them, feminized seeds are obtained.
Another method to get feminized seeds, and perhaps the most commonly used one, is the application of a solution of colloidal silver, a famous and easily found natural antibiotic. The solution placed on female cannabis plants induces the production of pollen, which fertilizes other female plants that will generate feminized seeds.
Feminized plants are photoperiodic plants and depend on hours of daily light to transition from the vegetative phase to the flowering phase. Photoperiod plants allow the grower greater control over the moment when the cannabis starts to flower by maintaining the light hours. Thus, growers can wait as long as necessary to remedy any problem with the plant still in its vegetative state, such as excess water or nutrients, or take clones or cuttings to ensure the survival of your favorite cannabis plants.
Less experienced growers should start with feminized plants until they get some experience. This is more likely to ensure that they are always healthy and within the correct growth parameters.
- Production of female plants
- Ideal for growers who want flowers
- Simplification of the cultivation process
- Not suitable for breeding
- Must be started from the seed
- Can turn into hermaphrodites
Automatic and autoflowering seeds
A few weeks after germination, autoflowering plants start flowering, regardless of the structure or health it presents at that time.(Shutterstock)
After feminized seeds, in 2008, automatic or autoflowering seeds appeared which were bred from Cannabis Ruderalis plants found in areas such as Eastern Europe, Russia, and Alaska. They flower in a shorter time, where there is no need for different photoperiods between the vegetative state and flowering, but they do require more attention.
Many people think that it is easier to cultivate, as it doesn’t need to change the photoperiod and the whole cycle happens in an “automatic” way. But not quite. A few weeks after germination, the plants start flowering, regardless of the structure or health it presents at that time. With that, the cultivator has no margin to correct eventual unforeseen events, such as excess or lack of nutrients, pests and diseases, and slow growth due to inadequate parameters.
- No need to change photoperiod
- Fast flowering time
- Lower yield
- Difficult and risky to clone
- Little time for care
Photoperiodic plants have the advantages of greater control by the grower during the plant cycle, a richer THC and CBD profile, better terpenes and higher production. There is also the advantage of producing clones from a selection of mother plants.
Autoflowering plants, on the other hand, have a faster cultivation, more than one harvest can be made during the year and the possibility of cultivation with the light always on.
|Type||Male||Female||Possible to clone|
Sativas, indicas, or hybrids?
Firstly, you need to decide whether you want to use it medicinally or recreationally. Certain cannabinoids are more present in certain genetics.
The differences between indica and sativa plants are quite significant, such as the shape, height and even the effects. Their morphological differences are much greater than those attributed to them in dispensaries and in popular culture, however.
Indica-predominant plants originally obtained from landraces in drier, more arid regions such as Afghanistan, Pakistan, and India have a shorter and more shrubby stature, a greater number of branches and a shorter space between nodes. This makes it a more compact and ideal herb to be grown indoors. They have a shorter flowering time, are easy to grow and especially under artificial light.
Indicas are more resistant to cold, require less water and do not handle high humidity well.
Sativa plants originally obtained from landraces in tropical and higher altitudes have a greater height, a “pine tree” structure, and the space between their nodes is greater.
Flowering times are longer and are usually a little more difficult to grow. They don’t like the cold, are more heat resistant and better suited for outdoor use.
Nowadays seeds that are predominantly sativa or predominantly indica are landraces which are still available from select breeders and keepers of cannabis history. Hybrids are more common and have some characteristics of each variety.
How to check if my seed is ok?
The best seeds have a rounded shape, are big and fat. The closer your seed is to these characteristics, the greater the chances it will germinate. (Shutterstock)
There are a few ways to find out if your cannabis seed is ready to be germinated or not.
You can start by using your senses of sight, touch, and smell to determine if cannabis seeds are good or bad.
To test using vision, you can resort to using a magnifying glass. The best seeds have a rounded shape, are big and fat. The closer your seed is to these characteristics, the greater the chances it will germinate.
Bigger, harder seeds are best. The surface should have a slight sheen.
They are dark in color (usually brown, black, or gray). The darker the color, the more likely they are to grow and produce a better plant. The dark bark means they came from a better-quality plant.
If they are pale, white, or light green, they were picked too early and are probably immature. This means they are not good and are unlikely to germinate. If they are light-colored and dusty, they are probably old and slower to germinate.
Another tip is to check if the seed has light streaks. Good seeds are usually darker and some look like they have tiger stripes and are also referred to as tiger backs.
You can’t always judge a seed by its color alone. It is necessary to know what is inside the seed. If you break a seed and it is oily and moldy, it is spoiled. If it’s black inside, it means it’s fermented and won’t germinate.
Other tests that can be done to verify that a seed is in good condition is the touch test. Just lightly squeeze a seed. If crushed easily, it probably won’t grow well. There should be no small cracks or holes. If they have these characteristics, they probably won’t germinate. They must not be wrinkled or cracked. If they aren’t cracked, you know they’re intact. If it resists the susceptibility test, the seed has a good chance of germinating.
The other test consists of placing the seeds in a container of warm distilled water for two hours. If they sink, they’re good. If they float, they are premature and probably will not grow and therefore are unusable. Healthy seeds are heavy enough to sink or sink once a little water is absorbed.
How to germinate my seeds?
To germinate seeds, four simple elements are needed: humidity, warm temperature, oxygen, and darkness.
Most seeds germinate between 24 and 72 hours, but some may take longer.
There are several methods to germinate a seed. The first and best known is germination on paper (it can be on napkins, cotton, or paper towels). In a pot, place a sheet of kitchen paper, separate the seeds so that there is a few inches between them and add another layer of paper on top. Both sheets should be damp but not soaked. If the paper loses moisture, add a little more water. Once the white root reaches 2-3 mm, carefully transfer the seeds to the pot. Do not close the pot, as oxygen is essential for successful germination. (You may also consider soaking the seeds for a few hours before placing them in the paper towels.)
Another method to germinate the seeds is with a glass of water, but it is not as effective as using paper. Place your seeds in a glass of water, preferably at a temperature of 22ºC. After 3-5 days, the seeds will start to open, and the small white radicle will appear. Then, just transfer to the soil already prepared to receive it. This is a simple method and suitable for first-time growers.
The grower can also place their seeds directly in the soil, in which case transplanting is not necessary. It is a safer option due to the fragility of the small root that appears when we germinate in a glass of water or on paper. Put the soil in the pot where your plant will be. Poke a hole to a depth between 10-15mm. Introduce the seed and gently cover it with more soil, but it is not necessary to compress it on top of the seed. Put some water on top to make the soil moist. After 4-10 days the grower will watch the plant sprout as the roots go under the ground.
Remember to always wash your hands and have all materials clean to prevent mold.
How to store my seeds?
Cannabis seeds should be stored in a cool, dry place. They can be stored in drawers and cabinets if there is no great temperature variation in these places. They can also be preserved in the refrigerator or even in the freezer.
Rapid temperature variations are the main problem when storing seeds and can harm genetic integrity.
If storing for just a few days or months, the grower can use a Ziploc-type bag, a glass jar, or an airtight container. If you want to keep the seeds preserved for a longer time, the most recommended method is in a closed vacuum package.
If you are going to keep your seeds in the refrigerator, choose a place further away from the door. That way, they suffer less from changes in temperature when opening the refrigerator.
Remember that by freezing your seeds every time they are thawed and refrozen, they become less viable.
By storing your cannabis seeds correctly and properly, they can last up to 10 years.
Special thanks to Sunshine Coast Genetics for helping fact-check this article.
How to Grow Weed: Germinating Cannabis Seeds
Jorge Cervantes shares his process for germinating cannabis seeds into healthy sprouts.
The gardening season is booming in North America, and it’s high time to start some tiny seeds that can grow into potent plants, says Jorge Cervantes, veteran marijuana cultivator and author of “The Cannabis Encyclopedia”.
1) Soak seeds overnight in a glass of plain water. They may float on the surface at first but should sink to the bottom in a few minutes. Make sure seeds get good and wet so that water penetrates the outer shell and growth is activated. Do not let seeds soak for more than 24 hours, or they might get too wet, suffer oxygen deprivation and subsequently rot.
2) Remove seeds from the water. Pour water out onto two paper (or cloth) towels on a dinner plate. Fold the towels over the seeds to cover them.
3) Drain the water from the dinner plate by tipping it to the side.
4) Place the seeds in a warm location (70°F–80°F; 21°C–27°C), making sure they are in darkness. Some gardeners go so far as to set the plate in a vertical position (so taproot grows downward). The seeds can also be set on a grate for drainage and air circulation.
5) Check moisture level of towels several times a day, watering once or twice to keep them evenly moist. DO NOT LET THE TOWELS DRY OUT! Let excess water drain away freely. The paper or cloth towels will retain enough moisture to germinate the seeds in a few days. Each seed contains an adequate food supply for germination. Prevent fungal attacks by watering with a mild 2 percent bleach or organic fungicide solution.
6) In a few days, seeds will sprout. Once the germinating cannabis seeds have sprouted and each seed’s white rootlet is visible, use tweezers to carefully pick up the fragile, germinated seeds and plant them. Do not wait for the white rootlets to grow more than 0.25 inches (1 cm) before planting, or growth could slow. Plant each germinated seed with the white root tip pointing downward. Take care not to expose the tender rootlet to prolonged light and air. Cover germinated seeds with 0.25 to 0.5 inches (1-2 cm) of fine, moist planting medium.
Other Tips for Germinating Cannabis Seeds
Over and under-watering are the biggest obstacles most gardeners face when germinating seeds and growing seedlings. Keep the soil uniformly moist but not waterlogged. Do not let the growing medium’s surface dry for long. Setting root cubes or planting flats on a grate allows good drainage.
A shallow flat or planter with a heat pad underneath may require daily watering, while a deep, 1-gallon (3.8 liter) pot will need watering every three days or more. A properly watered flat of rockwool cubes needs water every three to five days when sprouting seeds.
When the growing medium’s surface is dry (0.25 inches [1 cm] deep), it is time to water. Remember, there are few roots to absorb the water early in life and they are very delicate.
Some seeds have a very hard outer shell (testa) and are difficult to germinate. Such testy cases can be softened or scarified to allow water to penetrate. To scarify, line a matchbox with a piece of fine-grain sandpaper or emery board. Put the seeds in the matchbox and shake for 10 to 15 seconds. Remove the seeds and make sure they have been scuffed a bit. Just a little scuffing will allow water to enter and set germination in motion.
1) Set seeds in a matchbox with an emery board or sandpaper on the bottom.
2) Close seeds inside the matchbox.
3) Shake matchbox for 10 to 15 seconds to scarify the seeds.
This is an excerpt from “The Cannabis Encyclopedia” by Jorge Cervantes, world-renowned indoor, outdoor and greenhouse cannabis cultivator. A veteran marijuana grower, Cervantes brings 30 years of experience traveling, studying and writing to bear in his best work to date.
How To Germinate Cannabis Seeds: A Step-by-Step Guide
“It all starts with a seed.” Learning how to germinate cannabis seeds is essential to all future growing success. Properly popping beans puts you on the road to healthy plants and heavy harvests. But there are a few things to consider in order to master how to germinate cannabis seeds the right way.
Step 1: Choosing Seeds
First, you must decide on what seeds to grow and where to get them. Seek out trustworthy seed companies that have been around and have a track record of successful breeding. Take a look at our High Times Seed Bank Hall of Fame for a list of 50 of the most well-known and accomplished strain creators.
Don’t have seeds mailed to the location where you’re growing or planning to grow. Beginners might want to start with an indica-dominant strain that will stay small and stocky with a short flowering time.
Sativa-dominant strains tend to stretch more and have longer flowering times. If your seeds have been sitting around in storage for a while, check out these tips for germinating old seeds.
Step 2: Sprouting Seeds
Some people choose to use the moist paper towel method to germinate their seeds but I recommend just sowing them directly into the medium you plan to grow in. This reduces any stress the seedling will suffer through the transplanting process and secures the young plant firmly into your chosen mix.
Moist Paper Towel: Place seeds on a plate between two moistened paper towels. Put a plate on top to cover and within a couple of days, you should see the seed cracked open and a taproot emerging. Immediately and carefully (using tweezers) place your seed into your growing medium taproot down and water it in.
There’s nothing inherently wrong with using a moist paper towel, as long as you’re gentle with the emerging tap root and as long as you don’t let the taproot grow too long before planting. My belief is simply to start the plant in its own medium to reduce the likelihood of damaging the tender young roots and shoots.
Straight Into Medium: Poke a hole in your pre-moistened grow medium of choice. Drop your seed in about a quarter- to a half-inch deep. Cover the seed with more of your medium and tamp it down gently.
The important thing is to not plant too deeply and to keep the medium moist and warm for the best germination success rate. Clear plastic wrap placed over the top of the container helps maintain humidity. A heating mat underneath your plastic tray will increase your success rate as well.
Step 3: Seedling Care
Within a few days, you should see a minuscule green shoot emerging from the top of your medium. Immediately get your seedling under adequate grow lighting. Ideally, for the strongest growth rate, you want Metal Halide (MH) lighting, but Fluorescent or LED (Light-Emitting Diode) lighting works fine and won’t produce as much heat.
No matter what lighting you choose, always remember not to keep your grow-light too high above your seedling as this will make it stretch to reach the light and leave your young plant looking long and lanky.Use a timer to make sure the lights are on for at least 18 hours per day. Learning how to germinate cannabis seeds also means treating the emerging seedlings with the proper care.
Temperature and Humidity: You never want your seedlings to dry out. Keep your medium moist but not soaking wet. The air in your grow space should be kept warm, between 70-75 degrees Fahrenheit and with a relative humidity between 50-60 percent.
Use a thermometer/hygrometer to keep track of these factors at all times. As your plant adapts to its new environment, you will see new foliage sprouting forth. Your plants are now well into their vegetative stage of plant growth.
Final Hit: How To Germinate Cannabis Seeds
Now that you know how to germinate cannabis seeds, you’re ready to begin the process of growing your own weed. Just remember, provide light, food and water to your plants when they need it and keep the environment within acceptable levels of temperature and humidity. You’ll avoid so many problems by simply maintaining the proper parameters.
One last tip: Remember to label your seeds, seedlings and clones to avoid confusion and costly mistakes. Now get growing!