Jack Frost Landscapes & Garden Center blog for updates on sales and products as well as gardening tips and tricks, recipes, crafts, and more! 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 I have an indoor growroom and in my recent harvest I found seeds in the buds, but I’m sure there are no male plants in the room.
Stages of Growing Cannabis
Cannabis, weed, marijuana, kush, ganja – whatever you want to call it, it’s now legal to own and grow in the state of Virginia. So what does this mean for those interested in growing it?
Growing Cannabis for the first time can be quite overwhelming. A quick Google search will lead you to hundreds of results with more information than you can ever sift through. There’s so much to learn – lighting, pH, soils, training methods, curing, and so much more. Where does one start?
It’s really easy to fall down the rabbit hole of information online. The sheer amount of information can almost hinder you when you’re first getting started. I think it’s easiest to just get started and learn as you go.
Starting with gaining a general understanding of the stages of growing Cannabis is a great place to begin before you try growing for the first time. It will help you have a decent idea of what to expect along the way.
How long does Cannabis take to grow?
How long Cannabis takes to grow can vary based on the variety of the plant and conditions it is grown in. On average, from seed to harvest, it takes anywhere from 10-32 weeks (about 3-8 months). It’s a quicker process if you start with a clone (rooted cutting) or an autoflower seed. The biggest variability in how long a marijuana plant takes to grow will happen in the vegetative stage—after the seedling phase and before flowering.
Stages of Growing Cannabis
Every plant begins with a seed. Cannabis seeds should be germinated just like any other seed. They can take anywhere between 3-10 days to germinate, although it can happen in as few as 24 hours or as long as 2 weeks. To germinate, you can place the seeds in a damp paper towel, which you should then place in a dark place, such as inside a drawer. Check on them after a few days to see if the primary root, called the radicle, has emerged. This will look like a little white “tail” coming out of the seed. Once germinated, move them to damp soil.
Alternatively, you can place the seeds directly in damp soil to germinate and grow, without having the trouble of moving them. For this method, I would recommend a seed starting mix. These are usually lighter and fluffier than traditional potting soil, which gives your fragile germinating seeds a start on the right foot. We carry Coast of Maine Sprout Island Blend Organic Seed Starter Mix. It has additional perlite that aerates the soil and helps prevent damping off. It also has mycorrhizae, worm castings, lobster meal, hen manure, and kelp to get your plants off to a healthy start.
2. Seedling Stage
Once your seed has germinated, it’s now time to move the germinated seed from its paper towel to a growing medium. If you started them in a seed starting mix, you will want to move them from the seed tray to a larger pot with a high-quality potting mix, such as the Coast of Maine Stonington Blend Grower’s Mix. This is a super soil, that works especially well for growing Cannabis. It contains mycorrhizae, kelp, alfalfa meal, fish bone meal, worm castings, perlite, manure, peat, coir, and lobster compost that feed your plant throughout the growing cycle, with no need to use additional nutrients.
Plants are considered seedlings for about 2-3 weeks after germination. During this time, the plant should be moved to a spot with direct sun, if growing outdoors. If growing indoors, set your grow lights to run for 16 hours a day.
3. Vegetative Stage
After the seedling stage, Cannabis plants move to a vegetative stage. This is the time when the plant focuses on leaf production. It will not produce flowers at all during this stage, as the plant needs to grow plenty of leaves to take up enough photons (sunlight) to create the necessary energy to produce large flowers. The vegetative stage can last anywhere from 3 to 16 weeks, depending on the variety.
During this stage, indoor plants need 16-18 hours of light per day, and outdoor plants need at least 6 hours of direct sunlight (“full sun”), plus several hours of indirect sunlight. They will also need plenty of Nitrogen during this point, as Nitrogen is the nutrient that promotes healthy leaf growth.
The flowering stage is the last stage of the Cannabis plant life cycle. This is the time when your plant will stop putting as much energy into leaf growth and will instead focus that energy on creating the flowers (buds), which are used for medicinal and recreational purposes.
Stages of Flowering – Source: Katie Plummer
Cannabis is triggered to flower when the hours of light it receives are reduced. If you’re growing outdoors, you’re at the whim of the seasons and will have to wait until the sun starts to go down in fall for it to flower and then harvest. If you’re growing indoors, you get to play mother nature and can force your plant to flower at any point. When you’re ready for plants to start the flowering stage, change your lights to a 12/12 cycle ( 12 hours with the light on and 12 hours with it off ). You will see signs of flowering in 1-3 weeks . On average plants will be ready to harvest after 8-11 weeks of flowering.
Your plant will be ready to be harvested once flowers are compact and the pistils turn orange/brown. These pistils look like “hairs” coming out of the flowers.
To dry your Cannabis, hang sections of the plant upside down in a dark, cool space, such as a closet. You want to aim for 55-65% humidity and 60-70°F in the spot that you’re drying your plants in. Prolonged periods of light, friction from handling, and humidity/dampness can degrade resin glands, so you will want to avoid all of these.
During the drying process, plants lose roughly 75% of water weight, which increases the cannabinoid to weight ratio. It also helps equalize moisture content, preserve cannabinoids, and shed chlorophyll.
Cannabis is ready to trim once the stem snaps when bent, typically after 3-7 days of drying.
After your plant has dried, it’s time to trim! Trimming makes your fingers very sticky, so wear gloves if this is something you want to avoid. Simply trim off the larger leaves and stems. You can leave smaller sugar leaves if you’d like, as these still contain a good amount of cannabinoids and terpenes that provide the medicinal properties of Cannabis. It’s all personal preference of exactly how much you trim off. And you can save all the trimmings to make edibles, tinctures, salves, and more.
Curing is an essential part and the last stage in growing Cannabis. It helps the buds achieve full aroma. Curing is as simple as placing your freshly trimmed buds in a glass jar with a lid, like a mason jar. You’ll then want to place the jar in a cool, dark place, such as inside a drawer or in a cabinet.
During the first week of curing, you will want to “burp” your jars. This means you should open the containers once or twice a day for a couple minutes to allows moisture to escape and replenish the oxygen inside the container. After the first week, you only need to burp containers once every few days.
You should allow buds to cure for at least 2 weeks, but some people choose to cure for as long as 6 months. This helps stop the loss of moisture and to preserve flavors and aromas.
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.
I have an indoor growroom and in my recent harvest I found seeds in the buds, but I’m sure there are no male plants in the room. I’ve heard that light leakage can cause plants to become hermaphrodites. Is this true, and if so, do you have any tips for avoiding this?
Cannabis plants are monecious. This means they have the ability to be either male or female. Or in the case of hermaphroditism, they can be both. The reason to make sure there are no males or hermaphrodites in your garden is because male flowers make pollen. When pollen touches the white hairs on a flower, it makes a seed, and seeded weed gives you headaches. Even though there are reasons in nature hermaphroditism could be important, such as continuing the species in case there is no male present, hermaphroditism is generally a bad thing when talking about cannabis plants.
Light poisoning is the most common cause for a normal plant to hermaphrodite.
Light poisoning refers to the flowering night cycle of a plant being unnaturally interrupted with light. The best way to prevent this is to close yourself inside your darkened room during the daylight, and then after allowing a few minutes for your eyes to adjust to the dark, check for any light leaks from covered windows, door jams, etc. Also cover all timer and appliance lights with tape.
Negative stressors can combine with small interruptions of the light cycle to cause hermaphroditism, especially with less-stable, clone-only hybridized strains. When the night cycle is abnormally interrupted, it sends a mixed hormonal signal to the plant. This can cause a full female plant to throw some male flowers. Male flowers are easy to identify, especially when side by side with female flowers. Male flowers look like small bunches of bananas, which will take a week or two to swell before they burst and release their pollen.
Finding a hermaphrodite in your growroom can happen at any stage of the flowering cycle and is indicated by the presence of male flowers growing on the same plant as female flowers. As with all species in nature this can occur in varying degrees. A plant can become slightly or majorly hermaphroditic. In cases where singular male flowers are found between the branch and stalk nodes, you should be diligently removing them as they grow. You must re-inspect the plant top to bottom every few days to be sure pollination and seeding doesn’t occur. If you find male flowers (anthers) actually growing from within the female flowers (buds) the situation is a little more dire. You can still remove all the male anatomy as it appears, but it will be harder to find and much more prevalent. This is a horrible discovery that leads to a tough decision: Should you let the plant live and risk the whole crop being ruined by seeds?
In either case, once hermaphroditism has compromised the safety and purity of your sensimilla, the plant should not be propagated further. Remember, once a hermy, always a hermy. The plant pictured here is in the tenth and what should have been the final week of ripening, but a timer failed and one light stayed on continuously for almost two weeks, causing this vegetative regrowth. Because the light was continuous, the plant made no pollen. This method of re-vegging can be used to save a flowering plant you have no copies of, but be careful, as this may cause some strains to hermaphrodite.
Purposefully causing a plant to hermaphrodite is called selfing. Gibberellic acid or colloidal silver is typically sprayed onto the female plant. This technique is used to make feminized seeds and uses the plant’s ability to be both male and female to force a female plant to produce male flowers. The pollen contained in these male flowers can only produce female seeds. Just keep in mind that feminized plants should not be used for breeding, as they were produced without a true male, making them genetically inferior.