Cannabis Supercropping Tutorial
Supercropping cannabis plants is a high stress training technique that can be instrumental in effectively training cannabis plants. It is used to reduce the height or reposition branches or “colas”. Although it is considered “high-stress”, it is actually a fairly low-risk training technique if you follow the proper procedure. In this cannabis supercropping tutorial we address the common questions about supercropping cannabis plants. We cover why you should supercrop cannabis plants, when to supercrop cannabis, and most importantly how to supercrop cannabis plants.
What is Supercropping
Supercropping is a technique that allows you to bend and fold the plant to reduce height or reposition branches, stems or “colas”. It involves pinching the stem to soften the internal core or “curd” of the plant and make the outer fibers pliable. After the pinch, the plant can be folded at the pinch point to lower and/or reposition the stalk. Stalks that have been supercropped initially require support, but the stalk will quickly work to return to a vertical position, so the folded stalks also must be restrained in their new position.
Why Supercrop Cannabis Plants
There are several reasons to supercrop cannabis plants. The primary application is to manage the growth of the canopy especially during the stretch. Plants that are topped or trained to have multiple colas often benefit from supercropping to keep the canopy a uniform distance from the light. Supercropping can also be used to maneuver plants to fill areas where light maybe going unutilized. In addition, during vegetative growth, supercropping can be useful to create structures such as mainlines and manifolds.
Most growers turn to supercropping for the first time when they have individual stalks which rise higher than the rest of their canopy. These “too tall” colas will require you to raise the light, which reduces the efficiency of your canopy in harnessing the light energy. The taller stalks can also shade out the lower growth and stunt its development. In extreme cases, these “too tall” stalks may actually grow too tall for the space that they are enclosed within. Supercropping is the most effective way to lower the height of these “too tall” colas and maintain an even canopy. In the process, supercropping creates sections of horizontal stem which often provide additional growth points for stalks and buds.
How Does Supercropping Impact Yield?
You may be nervous that pinching and folding your plant will lead to a reduction in the yield, but this is far from the case. Many growers believe that supercropping produces even larger buds as the plant responds to the trauma. While there is a lack of scientific support for a hormonal benefit from supercropping, there is sufficient evidence to say that, when done properly, it does not reduce yields.
Supercropping may help you to produce larger yields by allowing you to manage the canopy and effectively spread out the plant. Supercropping typically involves folding branches to around a 90° angle. This increases the exposure and surface area of light to these branches. This not only helps improve the quantity of yield but also the quality because light is allowed to project over the flower sites more evenly, creating long and uniform bud growth over the entire length of the branches. The goal of any indoor cannabis plant training strategy should be an even uniform canopy. This allows the most efficient use of light energy, which maximizes the yield potential of your grow. For more on this, see our article, "Why You Should Train Cannabis Plants". Supercropping is an indispensable tool to help growers take control of plant shape and cultivate even canopies.
When to Supercrop Cannabis Plants
You can supercrop at any point when the plant is still growing vertically. After you pinch and fold the stalk down, it will bend back around to face the light. However, if the plant is no longer growing vertically then it will not turn around and it will not be well positioned to receive the light.
Supercropping during the stretch
The best time to supercrop is during the stretch, which is typically the second and third week of 12/12 lighting for photo-period strains. However, I have had success supercropping much earlier and later than that. I have supercropped right at the end of the stretch such that the tops just barely turned back around pointing upwards. This produced many sections of horizontal stem near the canopy and the bud sites all along them grew very well. Supercropping after “the stretch” is not recommended and is generally not needed because the plant is not growing vertically at that point.
Supercropping to create "Mainlines" or "Manifolds"
As you can see in the pictures below, I also use supercropping early in the plant training process when I am training plants to be “mainlines” or “manifolds”. Many growers use “low-stress training” (LST) instead, but I prefer supercropping these branches down rather than bending them down because it is safer and produces a stronger structure in the end. LST may be “low stress” when it goes well, but it is actually “high-risk” because it is easy to snap branches when bending them down. Supercropping may sound scarier, but it is actually the less risky option. Furthermore, the supercrop points become points of structural strength that help solidify the mainline structure (where the whole plant is grown from one node. Initially after doing the supercrop, those points are points of weakness, but strong knuckles develop which create structural strength for the “mainline” or “manifold” structure. By the time the plants are flowering they look like they have biceps!
How to Supercrop Cannabis Plants
There are two basic steps to supercrop cannabis plants. First you need to pinch, and then you need to fold. The pinch should be hard and the fold should be gentle! Once they are folded perpendicular, the folded section must be held up and restrained down. I do this with a simple soft-tie which encircles the stalk.
You can bring colas down as little as an inch or as much as 8-10 inches. What determines this is the distance between the supercrop and the tie down. When the plant recovers (within 12 hours) it will wrap around whatever tie down you put in place. The location of the tie down will determine the new location of the cola.
Supercropping Cannabis Plants Step by Step
- Select a point for supercrop just above a node with promising growth tip(s)
- Select a point for tie down and preset a soft tie to catch and restrain the cola. This often requires adding a bamboo stake to create a tie-down point. Netting can also be used to hold supercrops in position. You may have to be creative with how you support and restrain the stalk. If you prevent it from folding all the way over or repositioning itself vertically then you have achieved the goal.
- Squeeze the supercrop point with the pad of your index finger and the pad of your thumb (do not use your nails)
- Seriously squeeze that point, from both directions, as hard as you can. You should feel the plant "Pop" and go soft. It will make you a little sick to your stomach to be hurting your plant by pinching her so hard. Pinch hard - From both sides. It should be soft and pliable when you are done
- On mature stalks it can be very difficult to pinch hard enough to soften the tissue. Be persistent and remember to pinch hard and fold gently! If it is not possible to soften the stalk by pinching choose a different point for your supercrop.
- Gently lower the cola onto the soft-tie support that you have pre-set. Wrap the soft tie around loosely so she is supported and also cannot escape (see pics)
- If there is a long span between supercrop and support/restraint, set a bracing soft-tie at the mid point (to hold the mid point up!) The plant will really try to curve to escape, often trusting the midpoint down and increasing the angle of the supercrop. It is best to brace against this.
- If the outer skin of the plant opens then you should wrap the injury to protect it from air. Grafting tape is the ideal product for this application and is cheap and easily available. See more below
- The plant will curl around the support so the distance between supercrop and support/restraint is what determines how much vertical you are taking off
- You can decide where the cola is going to grow. Where ever you set the support will become the new location of the cola
Plant Injuries During Supercropping
The purpose of pinching the plant is to make the stalk soft and pliable so that the outer skin is not broken during the fold. However, it is not uncommon for the skin to split open at the fold anyway. This is not a problem, but should be treated. Whenever the outer skin of your plant is opened it is best to wrap the injury to prevent air intrusion. Grafting tape is the recommended solution for this problem.
Grafting tape is not a sticky tape. It resembles plastic kitchen wrap and clings to itself rather than sticks to the plant. Many growers and some amateur online guides suggest using duct tape, electrical tape, or other sticky tapes for these injuries. However, we strongly advise against using any sticky tape on plant injuries as they can cause more damage than they cure. Grafting tape is the professional horticultural solution to this problem and it is absolutely the right tool for the job.
Wrap the injury in grafting tape to create an air-tight seal. The grafting tape will expand to accommodate plant growth, but should be removed after 5-7 days. If you suffer a plant injury and do not have grafting tape on hand then you can cut a strip of plastic kitchen wrap to serve the same function.