Only a female marijuana plant makes flowers/buds that contain a usable amount of THC. Male marijuana plants only make pollen to fertilize the females with. Most growers will throw away any male plants that they encounter to keep them from fertilizing the female plants. If your female plants do get fertilized, they will use all their energy to produce seeds instead of making buds. This is good if you want seeds, but you will run into the same problem since half of the seeds will also be male.
If you would like to start a breeding program to make your own hybrids, I recommend using a method that creates all-female (feminized) seeds so that you don't waste time having to identify and throw out male plants.
Getting clones of female marijuana plants or buying feminized seeds online from a seed bank are other ways you can ensure that all your marijuana plants are female.
If you don't have a choice of seeds, and some of your seeds may be male (like if you just found seeds) than you will want to get your plants to reveal their gender right away so you don't have to waste time and energy on male plants.
How to Sex a Marijuana Plant
- Take a clone from the unverified marijuana plant
- Label both the clone and the mother plant so you know which clone came from which corresponding mother. If you don't label them, than all your effor will be for nought!
- Once the clones have established roots, change just the clones into flowering mode by providing them with a light schedule of 12 hours on, 12 hours off
- The clones should start revealing their gender in a week or two. Males will start developing balls and females will start developing white hairs. Click here for more information and pictures about how to sex a marijuana plant.
- Once you have determined the gender of your clones, you should make sure you throw away any corresponding male plants.