Low-Stress Training Cannabis Plants

The beauty of cannabis plants does not only reside in their amazing qualities, flavors, and effects, but also in their growth patterns. Cannabis plants are very mouldable, they can be trained to grow in many different ways. Growers shape their plants to increase the yields and improve on the natural qualities of their cultivars. Here we’ll cover the most practiced technique called Low-Stress Training (LST).

There are many creative ways to LST the plants. Therefore, we won’t be covering a step-by-step guide, but rather all the fundamentals that will allow you to be creative.


LST (Low-Stress Training)

The LST method, when executed correctly, changes the natural shape of the plants in order to expose them to the maximum amount of light. When plants start developing large fan-leaves, they naturally cover and shade each other, minimizing the amount of light absorbed by the covered leaves. Small buds in the interior of the plant barely receive any light, they are far away from the light source, and also grow very small in size. That’s where LST come in.

The basic logic behind LST is to slightly and gently bend the branches in order to develop a horizontally flat canopy, which covers a larger light-area in comparison with naturally grown plants. In addition to receiving more energy from the light, the distance between the light source and the canopy can be set at an optimal distance. Both of these factors lead to the development of larger buds and healthier plants.

This method produces buds similar in size, in comparison with one main bud that steals all the light and energy from the tiny buds beneath. LST also keeps the plants relatively short when done correctly, which is a true asset for indoor growers.

When the plants develop a couple of branches, approximately 3 weeks after the seedling stage, the branches are gently bent using twisty ties or coated wires, which are anchored to the side of the pot. When some of the branches are taller than the other ones, the grower should bend them so that the canopy becomes flat in shape. This needs to be done gradually and at the correct time, otherwise, the branches may snap.

How to apply the LST?

LST should be applied to the plants as early as possible, because of their growth patterns. During the plant’s growth, the branches become very thick and hard to bend, making them virtually impossible to LST. One should feel the flexible spots on the branch and bend them where it feels the most comfortable for the plant. The wires should be placed just before or after a fan-leaf or node, which prevents the wires from sliding.

When the branches are bent the leaves will be facing sideways or downward for a while, and after a couple of hours, they start facing up toward the light source again.

A lot of growers advise against bending the main stem and only applying LST to side branches. That’s because if something happens with the main stem, the majority of the plant, if not the entire plant, can be severely injured. However, when done gently and patiently, one can actually receive really good results from performing LST on the main stem.

Whenever tying the plant, one needs to make sure that the wires don’t move around along the branches, otherwise, they can damage the skin of the branch and also lead the plants to grow in unintended ways.

One could also use a tomato ring to tie the branches not only from the pot also from the sides, which is considered something between LST and ScrOG.

One should refrain from using threads or very thin wires, because they can cut through the branch when the plants grow, or when the thread/wire is moved rapidly.


Other techniques that can be used with the LST

LST is often used with topping and fimming techniques. After the plants develop about 4-6 nodes, the grower removes or cuts the top shoot, which creates two main branches instead of one, which produces a wider plant structure. This can be done several times, multiplying the branches. This takes the weight from the huge main bud and spreads it to the side buds. The plants should be strong enough for topping, but small enough to create a short bush.

The choice of strain is also important. Usually, when growing indoors, stretchy sativa-dominant strains are not ideal. LST indoors is mainly done on bushy indica-dominant strains with relatively short internodal spacing, such as our Mohan Ram@ (SWS09) variety.

LST can actually be practiced on autoflowering varieties, however, one should refrain from using topping and fimming methods because autoflowers don’t recover in the same way as photoperiod-dependent plants do. Too much stress and pressure on autoflowers will result in more recovery time which leads to smaller buds and weaker plants.

If by any chance, the branches are damaged during LST, which is not uncommon, one can save them by using some tape. The broken branches need to be placed in the correct position when taping the damaged area and hope for the best. Of course, to fix the branches they can’t be completely snapped off, the branch needs to be held by its outer layers.

LST during the flowering period

When the vegetation stage is over, and the plants are flat as a result of the LST work, it’s time for the flowering phase. During the first weeks of flowering, the plants can stretch significantly, so during this period, LST can still be applied. However after the stretch period is over, after about 2-4 weeks, one needs to leave the plants alone, and allow them to develop huge buds.

Those are the basics, if they’re all taken into account, one can LST the plants with confidence. This technique should definitely be practiced by every single indoor grower, in order to optimize those sweet cannabis plants.


Sweet Seeds S.L is not responsible for the misuse of the information contained in this article. Cultivation of cannabis may constitute a criminal offence or administrative misdemeanour; please refer to the legislation on cannabis in your place of residence. Sweet Seeds S.L. does not intend in any case to incite non-legal practices.


Texto: @Sweet Seeds®