Topping weed is one of the best high-stress training techniques available to growers. By topping the main stem of the plant it helps distribute the available energy more effectively. This helps more lateral colas develop rather than one large vertical cola. And ultimately, for you the grower, this means bigger harvests!
Topping cannabis: More than a simple hack
Left to its own devices, cannabis will tend to channel its energy into vertical growth toward the light. This time-tested evolutionary strategy serves the plant well in competition out in the wild, but it doesn’t ensure optimal yields. Improved yields are obtained when the cannabis plant is encouraged to grow laterally as well as vertically. Topping weed involves removing a section of the main stalk of the plant so as it becomes “bushier”. This enables plants to develop multiple colas and use the available light more efficiently.
Why is topping cannabis necessary?
During normal growth, the plant’s energy and hormones are directed upwards in one single channel. By cutting the main stem, the topping process encourages the plant to divert its energy into developing several colas. After topping, growth hormones are redirected from the main stem out laterally. This leads to the development of other node sites that otherwise wouldn’t receive the energy to develop.
Essentially what happens is that the small growth tips present below the top now receive the energy for further growth. They also receive more exposure to the available light as a result of removing overhead growth. The plant then diverts its available energy into several grow tips simultaneously until they become colas.
After topping, cannabis plants tend to grow wider rather than taller. The reason this happens is that when the dominance of the main cola is broken, topped plants tend to drive energy toward the lower lateral growths. These growths are typically starved of light under normal conditions but now develop into larger colas as they receive more of the energy. Wider plants mean more colas, more buds, and a bigger harvest, all for the same amount of light.
As well as the resulting yield benefits, topped cannabis plants also allow growers to control the shape and height of their plants. This is particularly useful for growers cultivating indoors in confined areas. In many instances a low roof means rampant upward growth is an issue.
When to top a cannabis plant
Topping cannabis is a relatively simple process, but should only be carried out when the plant is mature enough to survive the shock of topping.
Before attempting topping wait until the cannabis plant has developed 6 – 7 nodes. Waiting too long means that the plant will have put its energy into upward growth that’s only going to be cut off and lost. Topping at the right time ensures that lateral growth becomes a focus for the plant earlier. This prevents wasted energy through unwanted vertical growth.
How to top a cannabis plant
The first top will be the cutting of the main stalk. As a rule of thumb, this occurs just above the 5th node. This ensures that there are still enough side branches remaining on the plant for it to bush outward.
- First, you’ll need a pair of sharp pruning scissors. Make sure they are sterilised beforehand to prevent infecting the plant
- Find the 5th node on the main stem and make a clean cut just above it. Ensure that the cut is made at a slight angle. This helps to prevent water from accumulating in the cut.
- Be sure to monitor the plants for any signs of stress after topping. Make sure they have enough water and light.
- Wait at least a couple of weeks before topping again to allow the plant to recover.
- For subsequent toppings on the same plant, cut each side branch above the 2nd or 3rd node. Here the rules are less strict and the amount of subsequent topping depends on how “bushy” and large you want the plant to grow.
How many times should you top weed?
Cannabis plants are generally topped 1 – 3 times during their life. However, it should only be done during the vegetative stage. In this period of rapid growth, the plant can recover quickly from the stress of topping. Also, during this stage the plant will focus its energy on growing new branches, rather than producing buds.
Topping during the flowering stage can cause the plant to slow down its bud production. In such cases, it will then divert energy into new growth and negatively impact overall yield. Additionally, topping during the flowering stage can also make the plant more prone to stress and disease.
Mitigating plant stress while topping weed
Topping is stressful for a cannabis plant. To ensure optimal recovery and maximum benefit in terms of final yield here are some best practices.
- Gradual topping: Gradually top the plants rather than doing it all at once. This allows the plants to recover better and prevents excessive stress.
- Light and humidity: Make sure to provide the plants with optimal light and humidity conditions. The plant may need additional light to grow new branches and recover from topping.
- Water and nutrients: Keep the soil moist and provide the plants with the appropriate nutrients. Topping can stress the plant to an extent where it may require more water and nutrients to recover.
- Ensure enough space: Topping will likely make the plant bushier and increase the space requirements for new growth. Make sure the plants have enough room to grow.
Top your way to higher yields
Topping weed is a powerful technique that can help growers to increase final yield. With optimal energy diversion into multiple colas, the resulting lateral growth uses the available space and light much more efficiently. When implemented with care, this simple technique can lead to impressive yield improvements. So why not give topping a try and take your harvests to the next level?