Why is low-stress training often necessary for cannabis during the early stages of growth?
Cannabis plants exhibit phototropism, causing them to grow towards light, resulting in tall, upright plants with lower branches receiving inadequate light.
While the top buds may flourish, the lower buds suffer from poor light exposure, leading to sparse growth or even shrinkage.
So, what can be done to alter this scenario?
This is where LST technique comes into play.
With LST, you can bend cannabis plants, ensuring each leaf and bud receives uniform light distribution, thus enhancing overall yield.
1. What is Low Stress Training (LST)?
Low Stress Training, as the name implies, is a cultivation technique that controls the growth direction of plant stems by gently bending and securing them.
By gradually bending and tying the plant stems, the plant's branches are evenly distributed around the light source. This allows each leaf and flower bud to receive maximum light exposure, significantly improving the efficiency of photosynthesis.
Unlike traditional pruning and drastic topping, LST is a gentler and more sustainable technique. Instead of heavily pruning the plant all at once, you simply bend and secure them gently to guide the plant's growth in the desired direction. This method not only reduces stress on the plant but also allows for more flexible adjustments and optimization of the plant's form.
2. Tools and Materials Preparation:
Prior to starting Low Stress Training (LST), adequate preparation is crucial. These preparations will ensure that you can seamlessly execute the technique and maximize the plant's growth potential.
1) Below are the preparation materials you will need:
Plant ties: These ties are typically made of soft material to easily secure the plant's stems without causing damage. Options include Velcro, rubber, fabric ties (recommended), or dedicated LST training clips.
Small stakes or fixtures: Provide stable support to secure ties or soft ropes.
Scissors or pruning shears: Used to trim unwanted plant parts or adjust ties.
Bamboo stakes or plastic supports: These can be used to support and guide the plant's growth direction, especially in the case of larger bent branches.
Markers and tags: Used to record each plant's training progress and notes, aiding in better management and monitoring of plant growth.
Duct tape or adhesive tape: Serve as effective first aid when stems accidentally break.
2) Preparation:
Before starting LST, besides tools and materials, you need to do some preparation:
Observe the plant's growth status:
Ensure the plant is in a healthy condition, free from obvious pests, diseases, or nutrient deficiencies. Healthy plants adapt better to the training process.
Choose the right time:
The ideal time for LST is usually during the plant's growth phase when the stems are more flexible, making bending and securing easier. Typically, starting LST when the plant has grown to 4-6 nodes is most suitable.
Plan the training program:
Before bending and securing, observe the plant's form to determine where bending and securing are needed. Proper planning can avoid unnecessary procedures and enhance training efficiency.
Ensure suitable environment:
Ensure your growing environment has adequate light, water, and nutrients - essential conditions for healthy plant growth and successful LST application.
3.Specific Steps
Step 1: Choose the appropriate time to start LST.
When is the best time to start LST?
It is certainly during the plant's growth phase, before it enters the flowering stage. At this point, the plant's stems are more pliable and easier to shape. Specifically, the optimal time for LST is during the growth phase of the cannabis plant's lifecycle, typically when the plant has developed at least 4 to 6 nodes. At this stage, the plant is young and flexible, better able to withstand bending.
Step 2: Gradual Bending
Now, let's begin the practical operation. Choose a suitable position on the softened stem for bending. Typically, select a spot further away from the plant's main stem, as this can increase more branches during the plant's growth, thus enhancing yield.
When your seedling has developed four nodes and is growing the fifth, it's a good time to start bending the main stem.
Bending Techniques:
Bend the new growth: Bend the newer, softer parts of the plant. They are more flexible and less likely to break.
Gently start bending: Use your fingers to gently bend the stem, gradually guiding them to grow in the direction you desire. Remember, do not apply excessive force, as it can damage the plant's stem.
Secure in place: Insert an anchor stake 1 inch behind the seedling and another 1 inch in front, pointing towards your intended growth path. Inserting the stakes at a 45-degree angle can prevent them from loosening as the plant grows.
Prevent breakage: If you accidentally break the stem, immediately tape it back together. As long as both broken ends are securely fastened, the plant will heal quickly.
Step 3: Securing the Stem
To begin, cut a 3-inch garden soft tie/plant tie and fasten one end to the anchor stake placed behind the seedling.
Next, tie the other end at the base of the seedling stem, pulling slightly upward to provide initial support.
Then, cut another 3-inch garden tie and secure it to the anchor stake in front of the seedling.
Fasten the other end of the tie between the third and fourth nodes of the seedling, gently pulling the stem downward until it is roughly sideways.
Ensure the tie is securely attached, not rubbing or sliding on the stem as this could cause abrasion. If the stem cannot stay downward, secure it in multiple positions to distribute the pressure.
Step 4: Continual Observation and Adjustment
Do you think that's all there is to it? Of course not! LST is an ongoing process of adjustment and optimization.
Next, you need to continually observe and adjust. When the plant grows to about 3 to 4 inches from the top of the pot (approximately 4 weeks) following the initial training, repeat the two steps every 7 to 10 days. Each time you perform LST training, insert another stake 2 to 3 inches away from the last stake and tie down the top of the plant again.
Key Points:
Regularly check the plant's growth progres：
During the LST process, regularly monitor the plant's growth and the health of the stems. This helps in promptly identifying any stem breakage or excessive tension issues and taking appropriate measures.
Adjust LST based on plant's response:
Modify the position and tightness of the tying or soft strings according to the plant's growth response and stem changes. This helps maintain the plant's healthy growth and the desired shaping effects.
Adapt light and nutrient requirements:
After LST, changes in light exposure and nutrient absorption of the plant may occur. Adjust the light intensity and nutrient composition of its environment based on the plant's needs to support optimal growth and development.
Through Low-Stress Training (LST) techniques, you can effectively adjust the plant's growth form, maximize its photosynthetic efficiency, and yield. While the specific yield increase may vary due to factors such as plant variety, growth conditions, and training effects, growers typically see a 20% to 30% or more increase in yield compared to untrained plants. This method is not only applicable to high-yield crops like cannabis and tomatoes but also to other plant species that need to maximize growth in limited space.
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