Pay attention that growing marijuana may be subject to special restrictions and regulation in your country or state. Please contact your attorney to obtain advice before cultivating cannabis.
Topping cannabis is a technique to induce bushier growth and boost yield. Compatible with other agricultural crops, weed topping is a form of stress training, but low enough that the benefits outweigh the recovery time. After the top shoot is trimmed, where it got its name, the lateral shoots emerge and develop into flower-producing branches or the so-called colas. As a result, you can get more buds in one plant. If you are one of the novice growers curious to try this horticultural advantage, this article is for you. We covered all the fundamental aspects of why, how, and when to top weed plants.
Why Is Topping Marijuana Necessary?
Topping a marijuana plant is necessary to promote the side growth of branches and, therefore, more limbs to hold flowers rather than one whole superior stem. Excising the top part shatters the apical dominance, a plant phenomenon that caps the growth of lateral buds. Some of the benefits are explained in detail in the following points.
The primary reason for topping plants is undeniably to gain better yields. Un-topped bushes only initiate flowering at the single dominant shoot, resulting in a fewer harvest. If done correctly, this technique gives an equal chance for the side branches to flourish that will develop later as cola and reap a good harvest. Some weed cultivators prefer not to top their crops as it is laborious, and the results greatly depend on the growing conditions. Regardless, it is an excellent opportunity to experiment with your weed-growing skill and to mix and match the requirements suitable for the plant’s optimal growth.
Topping cannabis plants is a horticultural practice that modifies plant height. It is considered by many as the second main objective of topping a weed plant. Rather than allowing it to grow vertically, snipping the apex or the dominant tips lets the lower undeveloped buds pop out, subsequently maturing as side branches, advancing sideways, and making the plant look bushier. If you do not have enough space or a suitable growing area, topping is recommended to keep the plant low and to make it portable and easier to hide.
Size of Buds/ Nugs
Cannabis topping creates more sites for the buds to emerge as the secondary branches develop. The energy sinks — consumers of nutrients and plant food generated through photosynthesis — are therefore divided and would result in smaller buds or “popcorn” buds. Termed the lollipopping effect, the tiny popcorn-sized buds are often trimmed. It works like an Uno reverse card; to redirect the energy to the upper blooms to solve the issue. The plant should also have better access to light and be well-nourished to increase bud size. Despite the bigness issue, it is worth noting that the overall weight of the buds–regardless of enormity–from topping weed plants is still superior to untrimmed plants, which is vital in quantity-driven cultivation.
Who would not want a healthier plant? Another benefit of topping marijuana plants is improved overall resistance to pests and disease and better assimilation of photosynthates. Stems and inner branches are more exposed to sunlight and have better air circulation. The improved canopy architecture reduces the risk of fungal infections, which have a greater fighting spirit in gloomy places. UV light-sensitive arthropods like mites and aphids, which typically hide in the bush interior or on the undersides of the leaves, are also deterred from seeking refuge in a well-illuminated canopy.
A flatter canopy is created when topping plants. As the sun penetrates into the even foliage cluster, the leaves also intercept the maximum amount of sun needed to process light-mediated food assimilation: photosynthesis. It also eliminates the “parasitic leaves,” which do not produce net gain but rather depend on the food produced by other foliage. During the manufacturing of food, water and nutrient intake also peaks, making the plant generally healthy and robust. Greater photosynthetic efficiency increases the chances of producing better and bigger yields.
Increased CBD Content
One desired goal of producing marijuana is to extract a higher Cannabidiol or CBD content. In a recent scientific conference in Romania, a group of researchers presented a paper highlighting the benefits of topping in the chemical load. Topped hemp cultivars, 'Fedora 23' and 'Futura 75,' produced a significantly higher CBD content than the plants left unpruned. However, the researchers pointed out that the gains might vary on the variety and the climatic condition where the plant is grown. If these conditions are not met, beheaded plants will likely develop with similar CBD proportions compared to the typical ones.
Topping Cannabis Plants vs Super Cropping
Topping and super cropping are both promising techniques for boosting plant yield. While both approaches may look similar in the end product, the difference lies in the process. Topping employs the complete removal of the apical shoot as the plant stressant, while super cropping only involves pinching, bending, and tying the branches at a specific angle. The damaged plant fibers send signals to the plant to activate its defense system, causing it to assimilate more plant food–more food means faster growth and higher.
They are both high-stress training methods that introduce an artificial injury. Super cropping is like LST that needs to be tied, but topping does not require any bending and anchoring of branches; therefore, if you prefer to exert less effort on tying, topping might be the win-win.
Is Topping Plants the Same as LST?
Topping and LST, or low-stress training, follow the same principle of maneuvering the plant’s growth by inducing plant stress. Both practices disrupt apical dominance, which is accountable for single-stem vertical growth; the end product is a bushier growth with more branches and sites for flower bud development. However, the main difference is the introduction of stress. Topping is considered a high-stress technique and more targeted with the complete removal of the apical shoot, while the LST is simply the bending of the central stalk to redirect the growth.
Topping vs Fimming
Topping a cannabis plant is often linked to fimming, which has similarities and differences in the principle and the resulting product. The two methods are initiated by cutting the dominant tip to produce lateral buds. Topping is the complete clean cut through the apex, while fimming is performed incompletely, pinching only 75% of the plant’s tip, leaving an untidy growth afterward. Instead of having two new branches like topping, you will get 3 or more. One disadvantage of fimming is that it does not guarantee more plant extensions than topping–an imprecise method that would end up with a messy bunchy top. As a fun fact, the word fimming is like a more diplomatic way of saying, “F**k, I Missed (the right spot of cutting).”
Pros and Cons of Topping Outdoor Plants
Before learning how to top marijuana plants, various advantages and disadvantages are worth noting. They are listed in the following to help you delve deeper into the technique:
- Topped hemp plants create additional sites for buds to grow, increasing the potential harvest.
- It promotes growth sideways, reducing its size while increasing the surface area of the leaves to capture sunlight.
- A flat canopy of topped plants prevents shading issues of lower leaves, improves the efficiency of photosynthesis, and makes it easier to grow in confined spaces.
- The practice of topping will induce the plant to store more CBD in its tissues, as demonstrated by research.
- If done incorrectly, especially if the cut is long, this high-stress training inflicts immense trauma, which may reduce plant vigor and lengthen recovery.
- Hermaphroditism is another risk of topping plants, where male flowers might be produced aside from the desired females.
- As wounds are inflicted after topping, it may be a temporary predisposition to pathogens during the healing phase. Ensure that the tools are sterilized before use to prevent the issue.
How to Top Marijuana Plants
Whether it is your first time doing it or not, the steps on how to top cannabis plants are not complicated. Here are a few simple steps to do it:
- Count the number of nodes — You will need to count the number of eyes or nodes present on the stem, usually at the point where the leaves are attached. It is recommended to begin the procedure once it produces 3-5 nodes.
- Count the week after planting — Another reliable method before a topping cannabis node is when it reaches approximately 4-5 weeks. However, some strains proliferate early and are already suitable for topping as early as 2-3 weeks.
- Use a sharp blade or pruning scissors — Using a sharp blade or a pair of gardening shears, start topping 3rd node or the distal part of the shoots. After each cut, heat the edge in an alcohol lamp or dip it in alcohol before cutting other shoots to prevent cross-contamination of diseases.
- Top side shoots — While the main stem is already topped, the lateral branches that will grow can be once again cut to promote secondary branching. Wait another 1-2 weeks before performing the incision to allow your plants to recover.
When to Top Weed Plants — Best Time
The best time to top cannabis plants is when you see a sufficient number of nodes, usually after 2-3 weeks from sowing. How many nodes before topping? The minimum is at least 3, although you can delay it until it grows to 6. The time for topping outdoor plants and the indoor-grown ones are likely similar depending on their size. Do not perform it on saplings as they cannot handle the stressful chopping, which could result in prolonged recovery or, worse, death. If they survive, they might produce male flowers that are inferior to the females.
How Many Times Should I Top?
You can top your plant more than twice, which will exponentially increase the number of potential flower stalks and will extend the vegetative phase. Experienced weed cultivators can trim up to 5 times or more, multiplying the viable colas up to 36. However, don't be itching to deliberately chop new branches, as it can produce immense stress to the weeds. Wait at least 2-3 days or when the fresh stalks have reached a substantial size.
When to Stop Topping Outdoor Plants?
After months of hard work, stop chopping the tips about 2-3 weeks before it bolts the flower to redirect the energy back to the reproductive phase. You will also notice that the plant begins to increase in stem girth and length, which indicates that it is reinforcing itself to support a bundle of inflorescence. As it nears to shoot flowers, it is also recommended to complement this with a denser and more complete fertilizer mix.
What Week Should I Start Topping Plants?
The recommended week to begin topping plants is between the 2nd and 3rd week. Although it varies depending on the growing condition, this age is deemed suitable and already has a minimal number of nodes.
How Many Nodes Should Grow Before Topping?
Begin topping when you see at least 3 nodes, but you can postpone it until 6. Waiting a little bit will ensure that young plants will not suffer too much stress and can therefore recover much faster.
How Often Can I Top Feed My Weed Plant?
The frequency highly depends on the soil and the fertilizer you are using. We suggest following the manufacturer’s instructions for accuracy. However, as a general rule, drench a liquid fertilizer 1-2 times weekly after the soil surface completely dries.