10 Top Tips for Breeding Cannabis Plants

23 Nov 2022

Breeding cannabis is one of the most exciting things you can do as a grower and smoker. Producing a new generation of offspring from two of your favorite plants, can open the doors to new flavors, terpene profiles, increased yield, resilience, and much more. Creating a new gene pool in the comfort of your own home is easy to do, but also quite simple to get wrong. In this article, we cover 10 top tips to consider before you start your very first breeding project.

Top Tip #1 - Start with plenty of seeds 
If the aim of the game is to find male and female plants to select from, then you will need to use regular sexed seeds, and also plant a high volume. This can vary between 10-30 seeds depending on how practical it is, however the more seeds you start with then the more chance you have of having a big population to choose from. 

Our top tip here is to always plant more than you need to, and account for removing some plants based on size and structure alone. There is a much lower chance of finding any male plants when working with low numbers.

Top Tip #2 - Label everything 
It is a good habit to start labeling all your pots with the strain name and number. When working with multiple strains, it can be too easy to get the pots mixed up. Labeling your pots with stickers is the easiest way to catalog the plants and also help make notes as you get further into the project. 

Our top tip here is to use labels that will stick to the pots and not fall off over time with the heat and humidity from the grow room. Using plastic name tags that can be inserted into the side of the pots work well also. 

Top Tip #3 - Make notes from day 1 
Making notes is the most professional way to start and finish a breeding project. This will also allow you to learn much more about the plant’s characteristics, how it handles stress, the leaf patterns, internodal spacing, the stretch once flowering starts, the aroma of a stem rub, how well it roots, resin production, bud structure and so on. 

Our top tip here is to buy a book or journal that you use to keep a record and make detailed notes, that you can always refer back to when needed.

Top Tip #4 - How to select phenotypes 
Phenotypes are different variations of the same genetic, however will display traits differently from another. For example, if you have an Afghan x Haze plant and grew 20 seeds. You would see during the vegetative stage (18/6), which ones were more reflective of the short, stocky Afghani indica plants. The same goes for the taller, long leaf and lanky haze plants revealing themselves. 

Our top tip here is to have an idea of which traits you want to bring forward, and focus on those. This all ties in with having a goal to start with, which allows you to focus on a certain direction.

Top Tip #5 - Finding the best males 
When you have sexed your plants and are able to clearly establish which are male and female, then you can now decide which is the best male to pair up with your best female. It can be difficult to know which male will pass on the dominant traits and how well they will merge. If you already know what your goal is, and which traits are the most desirable to you, then working off structure and size can always be an easy way to decide. 

Our top tip here is to try and find male and female plants that are similar in height and structure, as this will oftentimes produce the most uniform progeny and hybrid vigor, displaying the best of both parental lines.

Top Tip #6 - Making feminized seeds 
If you prefer to make feminized seeds, then this is easy enough to do at home. The process in which female seeds are created is to treat the plants with silver. Using colloidal silver can induce the reversal process, however most professional breeders prefer to work with Silver Thiosulfate, otherwise known as STS. 

Our top tip here is to find out as much information as possible about reversing female plants to produce pollen, as the technique is quite difficult and will not always produce viable pollen. 

Top Tip #7 - Pollinating the females 
So you are now at the point where you have your chosen male plant, based on the characteristics most desirable to you, and have the female ready. The next step is to change your timers over to 12/12 and allow for the male and female to produce flowers. Male Cannabis plants will always produce pollen sacs and start flowering much earlier than females, as a form of synchronicity and to make sure the pollen does not come too late. 

Our tip here is to either pollinate a side branch of your female plant, or if you want a large number of seeds, you can dust the entire plant. You will notice the pistils turn orange within 36 hours as a sign of a successful pollination.

Top Tip # 8 - When should I harvest? 
Harvesting seeds is very different to harvesting buds, and there will be a point where the seeds literally start to pop out of their calyx and reveal a dark brown and hard mature seed. Seeds usually take between 5-7 weeks before they are ripe and can be harvested and cleaned up. Not all plants will produce big fat seeds with clear tiger stripes on, and some may produce small, gray circular seeds, or with haze plants little black seeds. 

Our top tip here is, only harvest the seeds when they are hard to squeeze and have a shell pattern or woody appearance. Avoid picking green or white seeds as these will not be any good. 

Top Tip # 9 - Storing seeds properly 
Once you have picked the mature seeds off the female plant, you will need to create labels for the seeds and be ready to store them for the long term. When labeling the seeds, you will want to refer to the pot label, and also your notes. An example would be if you had used Gelato and White Fire OG, the label would say 'Gelato #4 male x White Fire OG #8 female' Our top tip is once you have labeled the seeds, store them away in a cool, dry and dark place, or you can put them in the fridge until later use. 

Top Tip #10 - Have a goal! 
Before you even germinate your seeds, you should have a concrete goal in mind to which direction you want to go in. If you want to take a strain and make it better in your eyes by increasing yield or resin production, then selecting the most resinous plants will be your main priority. Perhaps the plan is to reduce flowering time, so your goal would be to find the quickest flowering plants to breed with. 

Our top tip here is taking the time to decide exactly what you want to bring forward and work from there! Concentrating on specific traits will make life much easier as well as the selection process.