A short description of cloning sounds simple enough: take a cutting from a mother cannabis plant, root it, and grow a genetically identical clone in less time than it would take to grow a mature plant from seed. But cloning can be very difficult to master. For one, it requires the careful selection of a mother plant. If the mother plant was prone to illness, its clones will be too.

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If your goal is to cultivate a healthy and potent harvest, you’re going to have to take cuttings from a seasoned mother plant, a gem that isn’t always easy to find. Second, newly cut clones are extremely delicate. Transplant failure is very common, so growers who are new to cloning should be prepared to be vigilant and to develop practical knowledge about the signs that indicate a cannabis plant’s health.

4 Tips For Successful Clones

Cloning is an intimidating process because it’s an easy one to mess up. Here are four rules that will maximize your chance of success.

Marijuana plants in beginning vegetative stage up close, growing in tent. iStock / HighGradeRoots

Do not clone sick plants.

You have a mature plant you’ve been really excited about, but it’s sick. The temptation to clone this plant is strong—if you use a healthy-looking cutting, you might get to save the phenotype. While this strategy may work, it will require a lot of effort to make sure that the very vulnerable transplant is not overpowered by environmental threats. Additionally, the transplant will have to work extra hard to repair any damage it’s carrying over from the mother plant. These factors significantly elevate the chance of failure.

Use sterile instruments to take your cuttings.

Remember, transplants are delicate babies that need extra TLC if they’re going to survive. Make sure that the tools you use to cut the trimmings from the mother plant are clean to protect your clone from infection. If you want to be extra careful, separate the shears you use for pruning from the shears you use from cutting clones.

Lay off the nutrients until you’ve transplanted your clones.

Giving your plants lots of nutrients sounds like a great idea to the novice grower, but plant nutrition is complex even when you aren’t attempting to complete the difficult process of cloning. It is possible to overwhelm cuttings with nutrients before they have properly rooted, so it’s best to wait until the roots have grown and taken to the final growing medium before adding nutrients.

Avoid using LEDS and HIDs on young clones.

CFL and T5 lighting may not be the most efficient sources of light, but they are easier for your vulnerable and overheating-prone clones to handle than the powerful energy coming from HIDs and LEDs.

3 Reasons to Clone Your Cannabis 

  • Clones take less time to mature. Since you are transplanting cuttings that have developed roots, you get to bypass the entire seed-to-sapling process. This shaves about a month off of your grow cycle. If time is of the essence, cloning is definitely your best (albeit riskiest) bet. 
  • Keep the genetics you want. The greatest advantage of cloning is that you get to control and protect the phenotype. If you find the best bud you’ve ever smoked, you don’t have to walk away from the experience empty handed. You can recreate it by using the plant that produced such a potent experience as the mother plant for your clones.
  • It’s one way to keep a self-sufficient garden. Cannabis plants are annual, which means that they die after blooming. Cloning is sort of a loophole to this natural cycle. Instead of buying new seeds in order to start the next season’s harvest, you can clone the previous cycle’s plants.   

Small medical marijuana seedlings at a medical marijuana grow operation. iStock / Danaan Andrew
Determining whether or not cloning is for you is just one consideration to make. Next, you have to decided how you want to proceed. There are many ways to clone, and many mediums to choose from, but the following three are the most widely used rooting mediums.

Rock Wool

Rock wool cubes are made from tiny filaments of heated glass. The texture of rock wool gives roots and water plenty of room to move while also providing a stable enough medium for the cutting. When compared to more high-tech mediums, rock wool is simple. It can also transplant easily into a variety of permanent growing mediums including coco coir, soil mixes, or hydroponic systems.

Furthermore, rock wool cubes are easy to clean and reuse. On the other hand, it takes time and creativity to figure out the best way to use rock wool for your clones. Novices to this medium will see some (or lots) of their clones die in the beginning, but in time, they are likely to enjoy a high success rate.

Peat

Young seedlings in plastic pots inside a greenhouse iStock / VladTeodor
This organic growing medium has been used for hundreds of years. It holds water well and is pretty cheap compared to other options. It’s also easy to set up. It isn’t difficult to find prepackaged trays already seasoned with a light nutrient solution.

There are several significant cons to using peat moss, however. For one, although it is a geologically renewable resource—it is the byproduct of biodegraded matter—it takes a much longer time to renew than it does for humans to use it. Additionally, it doesn’t do such a great job of aeration, which is why it is often used in combination with other mediums like coco coir or perlite.

Aeroponics

Aeroponics systems are ideal for those who want to avoid using traditional mediums. These systems use a fine mist of water and nutrients to allow suspended cuttings to root. Growers who use aeroponics to clone report quicker results.  Additionally, the systems are pretty straight forward. Plug them in, and they are ready to go without the need to set up messy or delicate mediums.

There are two major disadvantages to aero cloning. The first is energy. These systems rely on electric pumps to function which means that can be more expensive in terms of electricity costs. It also means that power outages become additional risk factors for already vulnerable clones. Second, aeroponics systems require regular maintenance to avoid gunky buildup. Without that maintenance, aeroponics systems become much less efficient.