The average indoor grower does not normally favour seeds in their cannabis garden. Having a few extra seeds may not be ideal, but they can be helpful if you don't want to spend extra cash on new seeds or have to deal with clones.
For breeders, creating seeds is part of the mission. The process is an integral part of creating all the wonderful strains we enjoy today. Whether you are looking to produce regular or feminized seeds, setting it up is easy to do. This guide teaches you how to get started.
Seeds are great for having lots of cannabis plants. It might be that you have found a strain that you love and decide you want plenty of seeds so you can continue growing it in the future. Or, it's possible you have the fantastic idea to create your own completely new blend of kushy genetics.
Once you start growing it becomes easy to scale up the operation and see the numbers start to multiply. Seeds are expensive, so having lots on hand is a useful way to keep your cycles going without breaking the bank.
Reasons you may want to produce seeds:
Producing seeds helps a grower find a strong specimen to breed. Many plants can be grown and the strongest females can be pollinated by either males to create regular seeds, or by another female to produce feminized seeds. More on that later.
Of course, the reason to produce seeds will be different for every grower but this is how to find faster, tastier and stronger strains. Regular seeds, particularly males, are beneficial in this way because they allow us to take the best parts of a strain from a different part of the world and pass them down to the next generation. With the right practice, the offspring tend to be tougher and pose more desirable qualities.
We can get an idea of how seeds are produced by taking a closer look at how male plants function. The male cannabis plant is normally disregarded for being useless in a grow room, however a male can be extremely useful, even to a novice grower. Most often they are kept separate, away from females to avoid pollination. Some growers will throw away their males at first sight but others may take advantage to get some free seeds out of their hard work and investment.
Male flowers are a crucial part in the discovery of new strains. The high production of feminized seeds nowadays means growers rarely have to deal with male flowers, but they are fundamental in the world of breeding cannabis plants and producing new seeds.
Pollen drifts extremely easily in the wind and a single male cannabis plant can quickly impregnate hundreds of females within a wide radius. The pollen attaches itself to the pistil hairs on a female cannabis flower and seeds begin to form. Those seeds produce plants with traits from both parents and have a 50/50 chance of being either male or female.
The easiest way to get seeds is by collecting pollen and applying it to female plants in a controlled way. You may just want one or two plants with seeds and not your entire garden. If that is not the case then you can just place a blooming male plant in that same room as your females and give it a good shake or point a fan at it.
For those not looking to produce thousands of seeds, it is also possible to pollinate only a few branches of a single plant. This is the method most growers use to get some extra seeds and still have plenty of budding females at the same time.
The female seeds produced from the pollinated plants can then be bred with other stable photoperiodic females to produce feminized seeds.
Note: Learn about producing seeds before fully moving onto to breeding. Breeding is much more complicated. Creating a stable plant with the desired qualities requires making multiple generations of seeds to 'lock in' certain characteristics.
Producing regular seeds is easy but the tricky part is not spreading the pollen to plants you want to keep seed-free. Be conscious of how you are handling your plants, especially when they are male. Pollen particles can easily attach themselves to your clothes, which may be transported to other areas if you are not careful.
Firstly, you need to choose a healthy male plant (with the traits you're looking for). For example, if you want a short, bushy plant, select a male that shows these characteristics.
Collecting pollen from a male flower is a simple 3 step process:
The pollen can be sealed in the plastic bag and kept in the refrigerator for a few days. Make sure the bag is completely sealed so no moisture enters otherwise the pollen will not work. The bag of pollen can be sealed in other zip-lock backs to keep it protected.
Pollinating the females with the pollen is just as easy as collecting it. That means you need to be extra cautious to not spread it all over the place. Preferably have the female plants you want to pollinate in a separate space to your main flowering room.
Changing/washing your clothes after collecting the pollen from the males is recommended.
To fertilise your female plants, simply do the following:
It is important that you give the flowers enough time to be fertilized before spraying them down with water. A few hours should be enough for the process to start.
The fertilized females start to produce seeds 2-4 weeks after pollination. Some strains may take a bit longer. Once the seeds have grown, the buds can be harvested and dried. Seeds are ready to be collected when the calyx splits and shows the brown husk of the outer shell.
Some seeds are likely to still be completely enveloped by the calyx, but once the buds are dry, they are easily removed. The seeds can be kept in zip-lock bags and stored in a cool, dry and dark place until you need to plant them.
Your seeds are now ready to be germinated! The seeds will produce a mix of male and female plants with traits from both of the plants you crossed. In a nutshell, this process can be repeated over and over until you have created a top shelf cannabis strain.
Feminized seeds are created with the aid of human intervention. They are not genetically modified in the way many people think. Feminized seeds come from forcing a female cannabis to produce male flowers. Hermaphroditism is a perfectly natural occurence in cannabis plants, we just encourage it when we want feminized seeds.
The pollen made by male flowers on the female plants is used to pollinate either itself or other females. The seeds produced in the female flower on the pollinated plant have over a 99% chance of being female.
There are many benefits to producing feminized seeds, the main reason being that growers are only interested in producing bud, not seeds. However, feminized seeds tend to be quite expensive, and for the cost of making them at home it becomes completely worth it.
Rodelization is the process of making seeds via environmentally induced stress. It involves stressing female plants by letting them pass their harvest stage. This forces them to produce male flowers (turn hermaphrodite) as an attempt to mate with itself or other females in the area before it dies.
Not all females react this way so you normally need a few plants to be sure it works, making it slightly inconvenient unless you have a lot of space and plants to spare.
The seeds produced from the stressed flowering female can be used to pollinate regular female plants. The seeds from the next generation have a high chance of being female, however the rates are not as high as they are when seeds are produced using colloidal silver, which we discuss now.
Tip: There is a small chance that through this method plants are more susceptible to hermaphroditism.
This is the most common and reliable way of making feminized seeds. It involves spraying plants with a solution that is designed to inhibit flowering hormones on a female plant. The process takes place in the first weeks of flowering as the plant begins to show its preflowers. The colloidal solution forces the plant to start producing male pollen sacs, from which the pollen can be taken and applied on another female.
Colloidal silver can either be bought or made at home. If you decide to buy colloidal silver, make sure it is from a reputable source and check with the provider for its quality. Fortunately, making it at home is very easy to do and requires just a few materials.
Materials you need to get started:
Attach the alligator clips with wires to the silver bars or coins and place them over the glass jar filled with distilled water. Use a Styrofoam support to hold the wires above the surface so the silver is hanging in the water. Connect the end of each cable to the batteries to create a circuit and your colloidal silver generator is ready to go. The following illustration may help:
How To Make Colloidal Silver:
How To Produce Seeds Using Colloidal Silver
Now we have the colloidal silver ready, we can look into how one would produce seeds with it. The process should take up to 3 weeks and requires you to apply colloidal silver daily to the plant you want to produce male flowers. You can start as soon as you have switched your plants from their vegetative stage to flowering (12/12).
Start by misting the node areas on the plant that you wish to see male flowers growing from with colloidal silver. Make sure you remember which spots you are working with, and if necessary put a tag on the branch as a note.
Mist once a day for 2-3 weeks or until you start seeing male flowers growing around the nodes. Once the male pollen sac opens you can harvest the pollen using the method we explained above. Other female plants can then be pollinated and the seeds produced from those plants will be feminized.
Using colloidal silver has a more stable end result to making seeds with rodelization. However, it is recommended to discard the plant you apply colloidal silver to, as it is best not to smoke it. Keeping it also increases the chances of further pollination of females.
Autoflowers were originally created by crossing the Ruderalis with Indica or Sativa photoperiod plants. Nowadays, finding regular autoflowering seeds can be tricky but is necessary if we are going to produce seeds with the automatic trait.
Autoflowering seeds are created in the same way as regular seeds, but using at least one parent that has strong auto genetics. The method you use depends on whether you are simply trying to produce seeds or create a completely new strain.
The best way to create autoflowering seeds is to cross two stable autoflowering plants. You can grow some regular auto seeds of the same strain, take the pollen from the best males and apply it to the healthiest female autos. The next generation will likely be an even more stable (and automatic) version of its parents but with no new traits.
Developing a new autoflowering strain involves crossing a regular auto with a photoperiodic plant, which is slightly harder. This is because the autoflowering gene is normally recessive and the photosensitive gene is dominant.
Getting the desired traits to stabilise requires you to breed the plants several times. Multiple generations of the same strain can be crossed until the recessive gene has been manipulated to a stable point.
Pollen application by UKauto from GrowDiaries.
Breeders focus on crossing to achieve specific results by combining two strains with traits they wish to inherit in new seeds. How compatible the two strains are depends on their genotype, or genetic makeup. That means crossing two Sativas is much easier than breeding an Indica with a Sativa. All cannabis plants are compatible, but producing stable seeds is trickier when the plants are not from the same family line.
When two strains are crossed, the DNA from each parents is passed down to the offspring. Each gene within the DNA consists of two alleles, one from each parent. A dominant allele is usually represented by a capital letter (e.g. 'T' for tall) and a recessive allele with a lower case letter. When two identical alleles are matched, they stabilise and is what is considered to be a homozygous gene match. When a gene is made up of two different alleles, it's heterozygous.
We can make an example, if 'T' indicates a dominance in the height allele, then 't' represents the genotype for shortness. Imagine both of the parents pose homozygous traits. All the offspring would be heterozygous.
Although breeding is much more difficult than producing a few seeds, it is certainly an interesting subject and helps us understand how new strains are created. If you are interested in making new seeds, feel free to do some further research on dominant and recessive genes in cannabis breeding, as there is a lot to learn.
One harvest of seeds can be enough to last you for years of growing, so why not give it a try? You'll save yourself a ton of money in addition to having loads of plants to experiment with. Who knows, you might even end up discovering your own strain that one day could become a cup winner.
This article will hopefully get you started producing your own seeds so you can get a step closer to becoming a master breeder!
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Early identification of tomato genotypes expressing mutations involved in the synthesis of anthocyanins. Acta Horticulturae. - Santangelo, Enrico & Picarella, Maurizio & Mazzucato, Andrea & Soressi, G.P.. (2012)
Cannabis DNA Typing Methods. - Coyle, H.. (2013)
Cannabis sativa and Cannabis indica versus “Sativa” and “Indica”. - McPartland, John. (2017).
This article was updated October 2020.