Cannabis Breeding 101: Growing Cannabis for Seeds

While some home growers incorporate clones into their gardens, the majority opt for seeds, fueling a thriving market for seeds from elite strains. Although certain seeds can be quite costly, skilled growers can consistently cultivate potent and flavorful flowers from them.

Crossing two strains typically results in plants that inherit the characteristics of one parent or the other. However, some may combine the best traits of both—a goal home growers should aim for when creating their own hybrids.

Creating high-quality seeds at home doesn’t have to mean committing the entire grow to seed production. It is very easy to produce outstanding sinsemilla (seedless) flowers, while simultaneously creating seed. 

Getting Started on Growing Cannabis For Seed

First, you will need to obtain seeds of the two strains you wish to cross. There are many seed banks and brokers from which to purchase your genetics. Decide whether you want your grow to produce indica seeds, nice balanced hybrid seeds, or sativa seeds, then buy two strains to accomplish that goal.

The strains you choose is a very subjective decision based entirely on your personal preferences. Do you like dank, skunky indica? Is a berry-flavored hybrid more to your liking? How about a piney and minty sativa?

A large part of the fun of breeding cannabis is matching up strains. Sometimes crossing two very different strains results in something entirely new and different. It pays to put some thought into which two strains you will use for your breeding project.

When you begin your grow for seed production, you will begin in the regular manner, growing your normal seeds rather than feminized.

Once the lights are switched to a shorter photoperiod (12:12 light-to-darkness), the plants will typically reveal their sexes within approximately one week.

Once the plants show signs of being either male or female, you must separate them and grow each in different locations that are well apart from each other. Males must be isolated from females.

Ideally, you want to grow at least a few plants of both sexes, eventually selecting the best of each for breeding.

The male with the best plant structure, resin production on stems, and the strongest terpene odor is the one to choose. Males have less-pungent terpenes than females, but usually some odor can be detected, even if it takes rubbing the plant stem gently with your fingers and then smelling them.

If a male plant is left in a grow room with females and releases pollen, it can completely ruin a seedless crop. Even trace amounts of pollen on hands or clothing can fertilize female plants. When a male pollinates females, it can result in thousands of seeds from heavily pollinated plants, making the flowers unsuitable for anything other than seed production. 

Under ideal circumstances, both sexes will be grown under HID or LED lights. For the home grower with limited resources, however, there is another option. Place the male(s) in a room with a large window that receives good sunlight. The males will mature to the point that they release pollen for collection. Then, following collection, you can dispose of them.

Pollen Collection and Pollination

Once your chosen male is releasing pollen for a few days, it’s time to collect it for use and storage. The easiest way to do this is to position sheets of aluminum foil under the male branches that are producing pollen. Shake the branches until pollen collects on the foil. The pollen should be yellow in color. Collect the pollen in a small container for immediate use and later storage.

There are a variety of ways to pollinate a female plant, but the information contained here is perfect for a home grow. It will allow you to produce a significant quantity of seeds and also produce seedless flowers for smoking or vaping. This pollination method will require the use of a small paintbrush.

To pollinate the female plant(s) of your choosing, you want to utilize some of the lower buds that have been flowering for only three weeks or so. By pollinating the flowers on the lower branches, you will still be able to harvest the choice colas at the top of the plant. If pollinating the upper flowers, you also risk seeding the entire plant from pollen that drifts down to the lower branches.

There are a variety of ways to pollinate the selected flowers. One of the easiest and most effect methods utilizes a small paintbrush. Simply dip the paintbrush into the pollen container and gather some of the yellow pollen. Then, brush the pistil hairs on the lower flowers of your choice.

By pollinating just a few buds, you will soon have anywhere from dozens to hundred of viable seeds for later cultivation projects.

Allow the pollinated flowers to mature for at least six weeks. If you wish to harvest the upper colas and unseeded buds before that time, by all means do so. Just retain the seeded buds so they can continue to mature. The quality of the seeded flowers will be very low and of little value for consumption purposes.

After you harvest and dry the seeded buds, break them apart on a level surface and collect the seeds. Store the seeds and any remaining pollen in a cool, dark place, where they will remain viable for an extended period of time.

Creating your own cannabis crosses is a fun and worthwhile endeavor. If you combine quality genetics, you will come up with something new and different in which you can take pride. The potential for greatness exists in every unsprouted seed. Imagine the possibilities!

Luis Cordova

Luis Cordova is a distinguished author, and renowned expert in cannabis cultivation, who possesses a Master's degree in Plant Biotechnology and Pharmaceutical Science. As a valued contributor to highly esteemed publications such as Cannabis Training University and Maximum Yield Magazine, Luis has emerged as a trusted source of guidance and knowledge in the cannabis industry. Having written thousands of informative articles, Luis is widely recognized for his comprehensive expertise on cultivating cannabis, both indoors and outdoors.