In this beginner's guide to cloning cannabis plants, you'll learn how to clone cannabis as well as the benefits and drawbacks of cloning cannabis versus growing with seeds.
What is plant cloning?
Plant cloning is a method growers use to make replicas of their best plants. Cannabis clones are genetically identical plants created through a process that does not involve sexual reproduction. However, Mother Nature can also clone plants without any human assistance. A clone plant can result from a new plant taking root after another plant has sent out a "runner," which is a type of modified stem. This natural asexual reproduction, called apomixis, occurs in hundreds of plants such as blackberries, strawberries, dandelions, and crab apples. Cannabis is not among the many plants that clones itself so taking cuttings from a marijuana plant is necessary to produce a clone.
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What are the benefits of cloning cannabis plants?
Besides the obvious — a genetically identical carbon copy of a strong performer — there are other reasons why a grower might want to clone a cannabis plant. Clones deliver:
1. Faster growth cheaper: Cloning cannabis plants bypasses the germination and seedling stages, which can take several weeks. Instead, a cutting taken from a mother plant can enter the vegetative stage of growth as soon as root growth begins. In addition, growers can save money by eliminating the purchase of seeds. A healthy and stable mother plant can produce countless cannabis clones without repeated investment in seeds.
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2. All females: Cannabis mother plants are sure to yield female plants, which means there is no chance of adding potentially destructive male plants to a garden. You can also achieve this outcome by purchasing feminized seeds from a seed bank, but this variety tends to cost more than regular seeds.
3. Multiple harvests: Not only will cloning allow you to replicate your best female plants, but the process may also yield more plentiful and frequent harvests. Indoor growers can grow all year round with cloning, while outdoor cultivators might be able to achieve an extra harvest before winter.
Are there any downsides to cloning plants?
Cloning cannabis plants is not a flawless process and there are some potential drawbacks. Cloning is more predictable than growing marijuana from seeds, but this benefit can actually be a downside if growers aren't careful. Any flaws that are present in the parent plant will show up in all the cuttings, which could leave a grower with a defective crop. Plant cuttings may carry pests or diseases originating from the mother plant that could be difficult to eliminate.
Cloned plants may also yield less cannabis than new plants grown from seeds. This is because clones have no taproot, the initial root that protrudes from the seed and extends deep into the soil. You can minimize the risks of a lower yield by growing cloned plants indoors and using the proper cloning technique.
How to clone a cannabis plant
The first step to cloning a cannabis plant is to gather the right equipment. Here's what you'll need:
- Healthy mother plant (at least one month old) with vegetative limbs ranging from 4 to 20 inches (10 to 50 centimeters) in length
- Razorblade
- Cup filled with water
- Rooting medium
- Rooting hormone
- Fluorescent light
- Cloning humidity dome or plastic bag to cover the cutting
Make sure you keep the mother plant in the vegetative stage and separate it from other plants. Before taking cuttings, sterilize the razor blade to avoid contaminating clone roots with bacteria and try to work in a sterile environment. On the cannabis mother plant, choose a branch that has at least four nodes and an appearance of new leaf growth. Cut the branch at a 45-degree angle and remove all growth underneath the top two nodes. After ensuring that you have made the cut at a 45-degree angle, place the cut end of the stem in the cup filled with water.
Application of a rooting hormone is recommended to prevent the formation of air bubbles, also called embolisms. A rooting hormone will also accelerate the growth process and provide a boost of nutrients. Dip the cuttings in the rooting hormone, then transfer to a rooting medium such as rockwool cubes. Put the rockwool cubes or other rooting medium under the humidity dome for moisture retention. You want to keep the humidity at an optimal level of 75% to 90% until the roots are able to absorb water.
Over the next week or two, you should see the formation of roots, which indicates that it's time to plant the clones. Once the clones have grown to maturity, you can store them in the refrigerator for up to three months if you aren't ready to plant yet. Wrapping the plant clones in a wet paper towel and placing them in a sealed plastic bag (aired out once a week) will keep them fresh. Do not place the clone plants in the freezer or any environment where the temperature drops below 40 degrees Fahrenheit (4.4 Celsius), as the cell walls could burst in the cold. Clones die in that kind of cold.
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Bottom line
For cultivators who want to replicate a favorite plant, cloning is a straightforward process with several advantages. Take notes as you experiment with cloning to better understand what techniques work best for you and your plants.