Advanced Cannabis Training: Topping and LST

Cannabis cultivation, both for medicinal and recreational use, has grown significantly in popularity over the past few years. With the increased interest in home-growing operations and more commercial-scale grow farms, the emphasis on effective and efficient cultivation techniques has become more pronounced. Among these techniques, plant training is a crucial aspect that can greatly influence the productivity and quality of the cannabis plant. This article aims to provide an in-depth view of two advanced cannabis training techniques: Topping and Low Stress Training (LST).

Overview of Plant Training Techniques

Plant training techniques in cannabis cultivation are employed to optimize the plant’s exposure to light, encourage better growth, and enhance yield. The primary goal is to create a more even canopy, ensuring each branch and bud gets adequate light. Topping and LST are two methods of plant training that allow the grower to manipulate the plant’s growth pattern to their advantage. Each of these methods requires a certain level of understanding about the growth cycle of the cannabis plant and careful execution for best results.


Topping is a high-stress training (HST) technique widely used in cannabis cultivation. The process involves cutting off the top of the cannabis plant, which breaks its apical dominance, or the plant’s natural tendency to grow one main stem. When this main stem is topped, the plant responds by promoting the growth of two new main colas (branches) instead of one, resulting in a bushier plant with more flowering sites. This technique can significantly enhance yield as more buds are exposed to optimal light levels.

To perform topping, it is essential to carefully identify the plant’s growth nodes — the points where branches extend from the stem or stalk. A clean, sharp cut should be made above the node to remove the growing tip or apical bud. It’s important to note that topping should be conducted during the vegetative stage of growth, not during flowering, to avoid stressing the plant and negatively impacting bud production.

Topping is not without its risks, however. It creates open wounds that could potentially invite disease and pests. It also induces significant stress on the plant, necessitating a recovery period before additional growth occurs.

Low Stress Training

Unlike topping, Low Stress Training (LST) is a technique that doesn’t involve cutting or wounding the cannabis plant. Instead, LST involves gently bending and tying down branches or stems to create an even canopy and encourage horizontal growth, promoting multiple bud sites.

The principle behind LST lies in the plant’s response to light. Parts of the plant that receive more light produce a hormone called auxin, which promotes growth. By bending and securing branches to grow more horizontally, more of the plant’s lower growth is exposed to light, stimulating the production of more buds.

LST is typically done using soft plant ties, string, or garden wire. The ties should be loosened and adjusted as the plant grows to prevent them from cutting into the growing branches. Regular monitoring of the plant is also important to ensure the ties are effective and the plant is responding positively to the training.

Comparison and Use Cases

Both topping and LST are valid techniques for manipulating cannabis plant growth, and they serve slightly different purposes. Topping is best suited for growers looking to increase the overall yield and don’t mind a slightly longer growth cycle, as the plant needs time to recover after topping. This technique also results in a bushier plant, which might be more suitable for indoor or stealth growing operations where vertical space is limited.

On the other hand, LST is a gentler technique that doesn’t induce stress on the plant, making it ideal for beginners or for growers who are cultivating strains sensitive to stress. This method is also useful for maintaining an even canopy in a larger growing space, where light distribution can be a challenge.


Cannabis plant training, including advanced techniques such as topping and LST, provides growers with tools to maximize their yield and plant health. By understanding and implementing these techniques, growers can manipulate their cannabis plants to ensure the optimal light exposure and growth structure that promote greater bud production. It’s important to consider each plant’s needs, growth stage, and the grow environment when choosing between these techniques. With patience, practice, and careful observation, growers can use these methods to significantly improve their cannabis cultivation.