How to clone cannabis

Cloning Cannabis

how to clone cannabisCannabis is a hardy weed that can adapt and sprout roots even under adverse conditions. If a lower branch gets trampled into wet soil, it might just sprout roots and grow into another whole plant. Really. Many years ago I was working on some bushy outdoor plants, pruning them for optimum growth.  I threw the tops into a 5 gallon pail and I left the pail next to a shed.  It rained for a few days, then the sun came out for a few more days.  When I went to empty the pail I was surprised to find that many of the water-soaked scraps had roots popping out of their stems, even though they were jumbled in a heap at the bottom of a wet bucket with virtually no light.  Some of them were healthy enough to grow into viable plants.  That’s because the plants I cut them from were growing strong in the long days of late June.

The first rule of cloning is, new clones are only as healthy as their mother plant.  It is possible to get rooted cuttings from unhealthy mothers, but they may be stunted and sluggish. At every stage, the health and vitality of these plants is the precisely what will determine success or failure of your project.  So, it is best to start with large, healthy mothers.  It is possible to take cuttings from smaller plants, but of course, there are only a few starts available on a young plant, and they do not have the full range of hormones found in adults.  It is best to take cuttings from a fully developed mother plant.  Later I will describe a technique to produce mother plants.  For now, we will just focus on the cloning process.

I have seen many cloning methods using all sorts of chemicals and mediums.  I have seen tiny one leaf starts the size of seedlings in Dixie cups, medium starts in pumped water devices, and I have seen huge stems jammed into cigar tubes full of peat moss.  Some of you might want to make or purchase clone machines, aeroponic devices that spray jets of water on the starts to produce many clones at a time.  I personally don’t use them because my methods work better for me.  There is also a ph difference between soil and hydro plants, but that’s a different issue.  My methods have a 95% success rate, and that is about as good as it gets.  Cloning is perhaps the single most important part of the cultivation process.  Successful propagation is crucial to rapid production in large cannabis gardens.  Cloning is also the most delicate part of the process, and it will likely take novices a bit of trial and error to master.  But if you follow my techniques exactly, you should be successful.

Here is what you will need:

  • A healthy mother plant
  • Stabilized water
  • Rubbing alcohol
  • hydrogen peroxide
  • Rooting hormones
  • Sharp scissors
  • razor blades
  • Paper towels
  • Rockwool cubes
  • Soaking bowl
  • Rooting trays
  • 40 watt fluorescent lights above a table in a clean, quiet, temperature-controlled room.

First, find top-quality stock and grow it to health and maturity.  Always allow at least 24 hours or more after transporting or transplanting before taking cuttings from a plant.  Clones actually root better when the doner plant is slightly unfertilized, so feed them half-strength for a week or two before cutting..   The mother should be happy and perky.  But remember, she does not like to have her heads cut off.  Always give mother plants several days to recuperate between cutting sessions.  This technique is a bit like taking a burning branch from one fire and using it to start a whole new fire.  The “fire” in this metaphor is the essential life energy of the plant.  You must have respect for the life force. Treat it like a tiny flame in the wind.   You must be gentle and careful.  Rushing through this process will only end in failure.

Stabilize your water.  This is the second most important aspect of successful cloning. If you have tap water from a city or town, the water is conditioned and adjusted to a suitable ph according to federal law.  If you have well water, your ph may vary wildly from the proper ph level, and you may have any number of minerals at unusual concentration levels, or you may have other contaminants.  In extreme cases it is advisable to use bottled water for cloning, but the fact is, bottled water is actually less regulated than tap water.  I have had success with Arrowhead and similar brands of bottled spring water, but you really want to know that your main water source is good for all ages of your plants, so it is probably best to simply stabilize your main source for cloning as well.  So, if you use tap water, the ph should be acceptable already, but there are definitely contaminants, like chlorine, fluoride and other trace elements that should be neutralized.  Simply store the water in any open top container for at least 24 hours so these contaminants can evaporate.  This one little trick can make a huge difference in your success rate.  If you use well water, you will have to purchase a good ph meter and test your water every month or so.  Do not use ph paper, ph drops, or ph meters with probes.  Those methods are not very accurate.  You need a real ph meter like the one shown in the hand-out, especially if you are going to do hydroponics.  You have to learn how to calibrate the meter, and you will probably have to use a ph buffer.  You want a ph of 6 to 6.5.  Any higher or lower will substantially reduce your success rate.  And here is a little trick that can make a real difference.  Add 1 ounce of 70% hydrogen peroxide per gallon of water.  Peroxide helps to clean the water of bacteria.  It also adds an additional oxygen molecule to the H2O.  Roots need a lot of oxygen to grow, so the peroxide really makes a difference in the success rate.

Rooting hormones are not all alike.  Some people have success with the gels.  I do not.  I stick with the old standard “Dip and Grow” brand liquid.  I use it at slightly less potent mix than the directions call for.  I actually throw away the bottles after using about half because evaporation inside the bottle always means the bottom half is stronger than then top half.  This is very strong stuff.  It does not take much to trigger the root cells.  I also use Rootone F powder.  I use that brand specifically—that is the only powder that works.  I have tried imitators that ruined every start in every batch.   I use that brand also because it contains a fungicide.  The most common threat is from infection of the cuttings.

Clean your tools.  Use the rubbing alcohol to wipe all tools and containers prior to use.  This will kill bacteria and also remove any manufacturing residue from new blades.  I prefer FIskars Microtip spring-loaded scissors, and regular single edge razor blades.  The razor blades are only used for one cutting session due to the crud and rust that tends to stick to the blade.

Rockwool cubes are the perfect medium for your cuttings.  They are available at all stores that sell hydroponic equipment.  I find the regular rockwool cubes work better than other mediums.  I use the 1.5 inch cubes.  Usually, there are a few in the sheet that are slightly weak or soft, and a few may have areas of rough rock that was not processed properly.   Discard any cubes that are not clean and solid.

I use a ceramic bowl to soak the cubes before planting the new cuttings.  Ceramic helps to keep the water temperature constant and is more cleanable and durable than plastic.

I do not use the common rooting trays found in garden stores.  The thin plastic does not contain the heat well enough, and the clear domes allow too much direct light.  Instead, I buy plastic shoe boxes found at any discount store.  I throw away the tops and put one on top of the other. You can also use larger size plastic containers.  Sometimes I simply turn them upside down on a table over trays.  The denser plastic hold heat and the opaque material provides a milder level of light than the common seedling trays.

Use standard fluorescent plant lights.  Too much light will burn the tender foliage. Do not use compact fluorescent, T5 fluorescent, or any other light sources.  And do not waste money on expensive grow bulbs.  Standard fluorescent 20 or 40 watt plant, aquarium, or even the new daylight bulbs found at the hardware store will work just fine.  I use two or three different brands or types of bulbs to blend a more complete spectrum.  During rooting, the babies need enough light to stay alive, but not more.  Starts are not ready for intense light unit they are well rooted.

The fluorescent lights should be hung 24 inches from the table top.  The room should be at a constant temperature of about 72 degrees.  I have found heat mats sold for this purpose are usually too hot and cause the babies to wilt and burn.  This is about coaxing the cuttings to root, and no amount of force will speed up the process.

Once you have prepared the water and lighting and cleaned your tools, take one rockwool cube and ream out the center with the scissors.  Put your finger at the bottom of the cube so you can feel the point.  Do not use a blunt object because that will compact the rockwool and make rooting more difficult.  Place the reamed-of rockwool cubes in the soaking bowl of stabilized water at room temperature.

Some people cut a bunch of starts at a time and then soak them in water while finishing the process.  I don’t do it that way because the babies tend to wilt.  I take each start from the mother plant, trim it, plant it in the rockwool, and place it in the rooting tray one at a time. That way everyone gets the immediate attention they need to root rapidly.

Use scissors to cut the tops at about a 3 to 4 inch height. Often I cut just below a node.  Then use the scissors to term the man leaf tops.  Cut just one quarter off the largest leaves.  Do not cut the small leaves at the center of the top.  We cut the leaf tips to keep the life energy at the center of start and to inhibit outer growth.  Do not over-trim.  Just a few snips of the largest levees is ail that is needed.

Next, use the razor blade to slice away the stem in a diagonal cut, or even a few diagonal cuts, like a spear tip.  We are exposing the rooting cells are just below the surface of the stem.  If there is a node at the bottom, cut away the leaf stem and any vegetable matter. Cuttings often root through the hole of a node.

Soak the lower inch of the stem in the Dip and Grow for 5 seconds.  Holding it in longer will not help.  Getting any amount of the hormone above the 1.5 inch level will ruin the strength of the stem.  Then dip the wet end into the Roottone and shake off any excess. Remember, these compounds work at the molecular level.  Very small amounts work best with no excess.

Gently place the stem into the hole in the rockwool cube.  Be careful not to rub off the hormones as you slide in the stem.  Again, feel the stem hit bottom by placing your finger under the cube. Then take a small piece of rockwool and gently stuff it into the hole to lock the stem in place.  It should be loose, but firm enough to keep the stem in place.  Try to make the cutting stand up straight, of course.  They may wilt at first if they are not handled with great care, but they should perk up to look normal within a few hours of being covered under light.

Place your new cutting into the tray with other starts. They may touch, but must not overcrowd or cover each other in shadows.  I place 4 to 6 starts per shoebox.  Cover the trays under light and let them sit for 48 hours. After the 48 hours, open the trays momentarily every following day to add fresh air.  As they get older, some leaves may yellow and die. Use the scissors to cut and remove any dead material as soon as possible.  Dead leaves will cause mold that can destroy every other cutting in the tray.  If the cubes become dry during this period, sprinkle just a few drops of water on the cubes. Do not let the cubes sit in the water.  The cuttings do not root well if they are totally saturated with water.

White roots begin to appear under the cubes 7 to 10 days after they are cut.  As soon as roots appear, plant then in small containers of a seedling mix comprised of 50% peat moss and 50% perlite.  Use stabilized water and make sure the water flows through the first watering. Do not allow any plants to sit in their own water for any significant period.  Recover the planted starts in the trays for an additional 2 days.  Open after day one to allow fresh air.  On day two, uncover and leave uncovered unless plants wilt.  If they wilt in open air, they need to remain covered another day or two.  Remove cover when growth is observed in the center stem.  Leave the newborn clones under fluorescent lights until roots are seen growing at the bottom of the small pots.  Once roots are firmly established, the starts are ready for a slightly stronger light.