Grafting Cannabis: Cultivation Guide for Growers

Grafting is a labor-intensive yet commonly undertaken practice within the vegetative and fruiting communities. However, within the cannabis community, this process is an often-overlooked skill. Grafting cannabis offers a number of advantages, and in this article, we will help you understand this high-stress technique better as well as its basic techniques and tips.

What is Grafting Cannabis? 

Grafting in the gardening sense is a procedure in which you take limbs from two plants and fuse them together to make a new plant. The first donor, which is usually the top part of the plant that bears fruit and leaves, is commonly referred to as the Scion while the second plant, which forms part of the lower stem and root system, is known as the Rootstock. In theory, gardeners will be able to grow multiple strains off a mother plant by using the grafting technique. It is a pretty simple and straightforward procedure but will, however, require a lot of patience to be done successfully.

Advantages of grafting include the following: (1) to shorten the flowering time of the Scion, (2) to improve the disease resistance of the Rootstock, (3) to optimize pollination as it is an asexual propagation technique, and (4) to essentially grow several varieties of cannabis strains in a smaller amount of space. Grafting cannabis is also especially helpful when you are looking to experiment with new strains without having to commit to growing an entire cannabis plant and waiting for it to grow out until harvest time. 

The origin of grafting, in general, is uncertain. Historians believe that ancient people may have stumbled upon natural unions of twigs and branches that were growing next to one another and then tried to copy the process using wind and abrasion. References to grafting appeared in many ancient texts from 500 BCE, where the method was routinely applied to several woody crops like apples, pears, and grapes. Nowadays, many cannabis growers use this process to increase their strain choices while keeping their number of plants at a convenient level.

How to Graft Cannabis?

There are a few basic requirements for grafting cannabis, including:

  • Isopropyl Alcohol
  • Scalpel or razor blade
  • Plumbers tape or PTFE tape
  • Plastic sealing bags
  • Plastic-coated garden wire
  • A glass of water at room temperature
  • Spray bottle with a pH6 vegetative nutrient solution

Before starting any grafting procedure, it is important to clean and sterilize your workspace and your tools to reduce the risk of infection and contamination. Additionally, grafting cannabis should only be done during the plant’s vegetative phase. Grafting the plants while they are on their flowering or blooming stage will dramatically reduce your yields and increase the risks of mold and rot.

Choose Healthy Donor Plants

It is important to consider the overall health of the donor plants. Make sure to choose only healthy plants as your donor Scion and Rootstock. Other important factors to consider include the strain of the cuttings, the length of the flowering stages of the strains, and the size of your cuttings. The strains should have the same flowering cycle to ensure that they finish the blooming stage at the same time. The size, structure, and girth of your cuttings should also be similar, if not the same, to ensure that the different tissue levels connect together faster and healthier. Cut off the branches in shapes that will allow you to fit the limbs like a puzzle piece to the mother plant. 

Choose Your Grafting Cannabis Method

There are several methods or styles of graft. Some of the common methods include the Whip Grafting technique and the Cleft Grafting technique.

The Whip Grafting technique, which uses a single slanting cut, is arguably the most popular grafting cannabis method due to its simplicity and speed. When opting to follow this technique,

  1. You start by preparing the selected healthy and compatible parts by removing most of the foliage on both Scion and Rootstock,
  2. Then start the cut from the donor plants by using a pair of garden shears,
  3. Take your razor or scalpel and make a diagonal cut of 45 degrees angle along the base of the Scion, 
  4. Next, cut the make a diagonal cut on the Rootstock to match the one on the Scion,
  5. Spray the cuts on both limbs with the vegetative nutrient solution,
  6. And finally, press both parts together firmly and tape them together. Make sure to wrap enough tape tightly around the cuts multiple times to ensure that light and air is blocked out from the cuts. This will allow both Scion and Rootstock to fuse properly and successfully.
  7. Next, take your plastic-coated wire and run it across the graft site. This further strengthens the bond.
  8. Lastly, to create the ideal environment for propagation, spray some nutrient solution inside your plastic bags and put this over your new branch, and partially closing the seal, leaving enough space for the new branch to breathe.

Make sure to go through the steps quickly as we want to lessen the exposure time of the parts to air. Air pockets can start forming at the base of the cuts, which can lead to issues during the grafting process. Instead, you can put any newly cut limbs in room temperature water.

Create the Perfect Environment for Grafting Cannabis

This method requires a lighting schedule that is set on a 24/0 light schedule considering the amount of stress that the Scion and Rootstock are placed under. By ensuring that lights are running continuously, you will help provide the required environmental needs until new vegetative growth is observed from the Scion. Failing to make sure that the lights run 24/7 will result in the graft attempt failing and the donor branches dying. Always opt for gentle sources of grow lights.

As mentioned, grafting cannabis requires a lot of patience as bonding of separate plants will understandably require time and the turnaround time may be quite slow. Many expert grafters say that the process may take up to two weeks or more to see results. However, this old-age technique boasts of increased vigor, yield, and favorable traits in cannabis plants.