There are two ways that you can go about breeding cannabis. The first is through sexual reproduction, where you cross a male plant with a female through pollination in order to create seeds. Those seeds can then be planted to create genetic hybrids of the two parent plants.
The second method is through cloning, otherwise known as asexual reproduction. Clones are rooted cuttings that are genetically identical to the plant they were taken from. There are many benefits to cloning that contribute to its popularity among both commercial and home growers. If executed properly, not only can cloning your cannabis be cost-saving, it has the potential to offer your garden a whole new level of stability and sustainability.
Through cloning, you can create a new harvest with exact replicas of your best performing plants. Because the genetics are identical, you’re getting a plant with the same characteristics, so if you come across a bud you really, really like, you might want to clone the plant it came from so you can produce more buds with the same effects. Consider taking clones from your garden if you are looking to select and replicate plants with desirable features such as flavor, cannabinoid profile, yield, grow time, etc.
Although it sounds complicated, cloning a cannabis plant is a relatively straight forward process. You just need to know how.
Cloning cannabis involves cutting a piece of a plant and giving it the opportunity to grow new roots from its stem. Yet, if you do some reading around on cloning cannabis on the internet, you may find different opinions on the best way to go about it. While some cloning methods may vary, some guidelines apply to all methods. To get you started with cloning right, the first piece of important advice is to always select your best and healthiest plants for cloning. Let’s look at the required steps for cannabis cloning in more detail.
What you will need to clone your cannabis plants?
- A healthy “mother” plant where you want to take clones from
- A scalpel, razor or sharp scissors
- Starter cubes (Rockwool cubes, Rapid Rooters)
- Cloning gel or cloning powder
- Adequate “mild” light for your clones. A low wattage CFL grow light or a special light for clones and seedlings is ideal
- High-proof alcohol for disinfecting your tools
- Optional: Heating mat, mini greenhouse or humidity dome, “pH down”
Preparing your mother plants for cutting will require a few steps:
- Make sure you withhold from fertilizing your plant within the days leading up to taking your cuttings. This will allow the nitrogen to work its way out of the leaves of your plant. When you take cuttings, an excess of nitrogen in the leaves and stems will trick your clones into attempting to grow vegetation instead of diverting energy to rooting.
- Work in a sterile environment. Do everything you can to avoid over-agitation of both your mother plants and new cuttings.
- Look for lower branches that are sturdy and healthy. If you are transplanting into rockwool, match the stem with the rooting hole of your cubes to get a proper fit. Otherwise, look to take cuttings between 8-10 inches with several nodes present.
- Cut as close to the main stem as possible with your razor at a 45 degree angle to the branch. This will increase the surface area of your rooting space, promoting faster growth.
- Place your fresh cutting immediately into water to prevent air bubbles from forming in the stem. Bubbles will prevent water from absorbing into your stem and can kill a new clone. Many growers choose to make additional incisions in the stem before this step, arguing that it helps increase rooting potential. Take this time to do that before transferring your cuttings to water.
When is the right time to take a clone?
The right time to take a clone is when the plant is at least five weeks old from seeding and is growing multiple side branches and shoots. You will know by handling the plant shoots if they’re older woody branches or soft tissue. Either of these can be cloned as long as you know what you are doing. The worst thing you can do is take a fresh shoot with inner walls that are still hollow—this usually ends up with the cutting wilting and becoming a soggy mess within minutes.
There is a technique called “monster cropping” that can help you to grow more efficiently. When using this method, you don’t necessarily need to keep a motherplant to ensure continuous harvests. Combining this method with other forms of training, with a SCROG (Screen of Green) for example, can help to cut down on energy costs and increase yields. Monster cropping is a relatively new training technique and is also known as Flowering Clones. It works from the phenomenon that clones taken from a flowering plant grow extremely bushy when they are reverted into vegetation phase. Monster cropping can also be successful when growing outdoors, or in a greenhouse.
Do I need to use rooting hormone?
No, you do not need to use rooting hormone, as the plants naturally create growth hormones that encourage them to produce root cells and cease the growth of stem cells and leaves. You can always give your clone a supplemental hormone, which is often IAA (indole-3-acetic acid), the most naturally occurring plant hormone of the auxin variety. Some seaweed extracts also contain natural growth hormones that stimulate root-cell development.
What is the best medium in which to root my clones?
When it comes to rooting mediums, there are three predominant schools of thought:
Use rockwool cubes or a non-soil equivalent. Rockwell provides a great environment for clone rooting due to its terrific airflow and moisture retention. You can find these cubes at most any grow store or online.
Transport your clone into soil. When using soil, don’t choose one with an abundance of nutrients, and make sure you don’t over or underwater your soil when attempting to root your clones.
Root in water. Water cloning requires no use of rooting hormones or mediums. You just drop your cutting in water and keep it there until roots and new growth begin to develop.
What temperature is best for my clones?
The temperature and humidity of your cloning area needs to be warm and wet. This is the main reason why growers experience stunted clones or rooting that can take anywhere from 21 to 35 days. If your growroom temperature is below 68°F, your clones will avoid rooting. Maintain a humidity level of 70% and a temperature of 75°F.
Why is there is fuzzy mold growing inside the propagator?
If you’ve left your humidity dome for several days untouched, you may notice that stagnant air and wet conditions have caused your clones to grow a furry white fungus. When you touch the plant material, it will feel soggy or mushy. This is a major setback, especially if you are depending on growing out a certain number of plants. To remediate this, remove the lid, immediately dispose of the infected clones and introduce fresh air into the propagator. You should lift the lid for 30 seconds daily to encourage the exchange of fresh air, taking care to maintain proper temperature and humidity. Cutting a quarter-size hole into the clear plastic at either end of the lid can help circulate air as well.
How big does my propagator need to be?
From my experience, the bigger the propagator, the better it is for the clones. You can easily root cones in cups and cover them with cling-wrap film and an elastic band if you must; however, using a propagator that is 12 inches tall provides plenty of room to take larger, more mature clones. Avoid using a small propagator that is 6 inches tall or less, as you’ll only end up with cramped clones touching the wet sides and roof of the plastic dome.
Why does my clone have white bumps around its base?
This is the process whereby a cutting produces root cells. These first nubs are the earliest indicators that your clone is developing roots. At this stage, the clone is becoming an established, independent plant, so don’t disturb these delicate primordia. After it forms a fully developed root system with fibrous root hairs, the clone will independently photosynthesize and begin taking in nutrients and growing.
When will my clones start showing roots?
This is determined by a number of variables including temperature, humidity, lighting and the overall quality of the plant. As long as your cloning room is at a humidity level of 70% and the room temperature is 75°F, you should see the first roots emerging within 7-10 days. If you are using larger clones, they will root first due to their size and maturity.
Does it matter which part of the mother plant a clone is taken from?
Many growers swear that clones taken from the base of a plant will root first, perhaps because they were closest to the mother plant’s roots. Other growers testify that cloning from the top using the mother plant’s newest growth will produce the fastest-rooting clones. Cloning cannabis is a game of patience, and trying to rush the process will only frustrate you further. As long as the cuttings you take have at least one internode and some leaves, you’ll have success.
Why are my rooted clones starting to wilt after taking them out of the humidity dome?
This is called the hardening-off process. Your clones have been acclimated to warm and wet conditions and now need to get used to life outside of the humidity dome. It will not take long for them to adjust, just like a fish that’s been transferred into a tank of fresh water. If your clones are wilting and look like they’re about to die, improper temperature or humidity is to blame. You must remember that you’re mimicking the spring season. Slowly introduce them into their new environment that contains intense lighting and wind from fans.
Can I transplant the rooted clones to any grow medium now?
Once your clones are hardened off and you are happy with the way they are coming along, you should prepare the grow medium into which they’ll establish themselves and grow. The roots of the clone will want to dig down as far as they can to anchor themselves firmly into the medium. Feed them very lightly at this stage and encourage more dry periods to avoid having a waterlogged medium. Roots will push out aggressively when they’re looking for moisture and available nutrients.
Is there any other way to root clones?
If you find that the conventional technique isn’t working, you can look at other cloning methods, such as using a bubbler or air layering. Using a bubbler entails sitting freshly cut clones in a bubbling oxygenated nutrient solution with a water temperature of 75°F. Air layering is used in bonsai-tree production and can result in some large and sturdy foot-long clones when done correctly. It’s something I personally do when I want to take a large side branch and grow it as an independent clone. The amazing thing is that it’s actually performed on the plant as it’s growing normally. I strongly recommend you research this technique before attempting it, especially if you are new to plant biology.
Do I really need to cut the leaf blades down?
You do not need to remove any of the leaf blades, but it does encourage the plant to cease photosynthesis and almost shut down. This is how root cells are able to form in the dark, wet conditions of the rooting cube. Many growers simply cut a healthy clone and then, once it has rooted, allow it to grow with all its leaves intact.
It’s been 14 days and still no roots. Am I doing something wrong?
Most likely you’ve messed up one of the basics and now your pristine clones are back to square one. If you remove the clone and look at it closely, you may see that there’s no root development. In fact, there might be just a soggy decaying tip where a healthy wooden stem once sat. If this is the case, then learn from your mistake and apply root hormone, change to a fresh new medium and make sure your temperature and humidity are at the proper levels.
How many clones can I take off a mother plant before it’s excessive?
It may be called the mother plant, but this does not mean you can butcher it. You should nurture the mother plant and raise it to produce as many healthy clones while also pruning it to fit in your space. You shouldn’t take too many clones at once, as you will eventually be left with a large woody stem with few shoots remaining. You also should consider using a new mother plant after multiple generations of cloning have taken place.
What are the top tips for cloning?
One of my personal favorite techniques is to double dip. This involves taking a clone and wetting the bottom inch with water, then dipping the wet part of the cutting in rooting-hormone powder. Once the powder has fully stuck to the wet part, you can now dip it into a rooting gel to seal that rooting powder in and provide a double dose of natural growth hormone.
When you clone a cannabis plant, the clone will always be the same age and at the same growing stage as the parent. One of the best times to take clones is just before you flower the mother plant. Don’t hesitate to grow more clones than you think you will need. Not all clones will always turn out a success, especially if you’re still new to cloning. It can be a good idea if you grow more just in case you should lose some. Be patient. Most clones should start rooting in several days, but some can take several weeks until they grow roots. You can keep desired mother plants for your clones in the vegetating phase for a long time. If you prevent them from flowering by keeping them under a vegging 18/6 light schedule, you can have mother plants that will give you clones for several years!
Good luck getting 100% success rates on your clones and becoming the farmer you’ve always wanted to be!