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Low Stress Training (LST) in Cannabis Plant Cultivation

August 16, 2021 / in Growing Cannabis / admin

Photo of a Cali Deli (Nepali x OG Kush x Cheese) cannabis plant with applied Low Stress Training, showing the manipulation of branches for even growth

In the intricate dance of plant cultivation, techniques that encourage optimal growth and yield without causing undue stress to the plants are golden. Enter Low Stress Training, or LST. This method, deeply rooted in the principles of understanding plant behavior, has carved a significant niche in modern cultivation.

By gently manipulating plant structure, LST ensures each part gets its share of vital light, promoting even growth and maximizing potential yields. As urban gardens become more prevalent and space becomes a premium, the significance of techniques like LST has never been more pronounced. Whether you’re a novice or a seasoned cultivator, understanding and effectively implementing LST can elevate your gardening game, offering bounteous rewards for a delicate touch.

Understanding LST: The Basics and the Science Behind It

Low Stress Training, or LST, is a revered cultivation technique, marrying the hands-on approach of growers with the intrinsic growth patterns of plants. But to truly grasp its efficacy, one must delve into the chemistry and biology that underpin it.

What is Low Stress Training?

Low Stress Training is a method where growers gently manipulate a plant’s structure to steer its growth in specific directions. This is done without cutting or injuring the plant but rather bending and tying down branches to encourage a more horizontal growth trajectory.

The Chemistry Behind LST

The rationale behind LST isn’t just about the physical redirection of branches; it has a deep-rooted chemical basis:

Auxins: These are plant hormones, with indole-3-acetic acid (IAA) being the most prevalent. Auxins play a crucial role in determining the direction and type of plant growth. They are primarily produced in the plant’s apical tips (the topmost, youngest part of the plant). When the apical tip grows upward, unrestricted, it produces more auxins, suppressing the growth of side branches. Through LST, by bending the main stem and branches, you’re redistributing these auxins, allowing side branches to flourish and potentially become main colas.
Light Absorption: Plants rely on photosynthesis, a chemical process using light to convert carbon dioxide and water into glucose, a type of sugar. This process is governed by pigments called chlorophyll. By maximizing light exposure through LST, more of the plant’s leaves can efficiently engage in photosynthesis, leading to increased energy (glucose) production.
Stress and Secondary Metabolites: Plants produce secondary metabolites like terpenes and flavonoids, in part as a response to stress. Gentle stress, like that induced by LST, can potentially boost the production of these compounds, enriching the aroma, flavor, and therapeutic value of the plant.

How does LST differ from other plant training techniques?

While there are several training techniques that cultivators employ to shape a plant’s growth, LST stands apart due to its gentle, non-invasive approach. Here’s a quick breakdown:

Topping: This involves cutting off the top of the plant to encourage lateral branch growth. It’s more stressful for the plant and causes a temporary halt in growth.
Supercropping: Stems are intentionally, albeit carefully, broken to change their direction, becoming stronger upon recovery.
FIMing (F*ck I Missed): A pruning method that involves a partial cut of the newest shoot, leading to bushier growth.
LST: Unlike the methods mentioned above, which involve some form of cutting or intentional damage, LST is all about the gentle bending and securing of plant branches.

For a deeper dive into these and other techniques, you can refer to our comprehensive cannabis plant training guide. In essence, each method has its own merits and challenges, but LST stands out for its minimal stress and non-intrusive nature.

Why Implement LST?

The art of cultivating plants, especially cannabis, involves understanding and harnessing various techniques to optimize growth and yield. Low Stress Training, or LST, stands as one of the most favored methods among cultivators, and here’s why:

1. Enhancing Light Exposure for Even Canopy Growth

In nature, plants naturally grow upwards towards the sun, leading to a dominant main stem or ‘cola’. However, in cultivation setups, especially with artificial lighting, this natural growth pattern can overshadow and limit the light exposure of the lower branches, leading to uneven growth. LST addresses this by bending and positioning the plant in a way that exposes more of its parts, especially the budding sites, to the light source. An even canopy ensures that no bud remains in the shadows, promoting uniform growth across the plant.

Low Stress Training applied to a Cali Deli

2. Maximizing Yield Without Compromising Plant Health

Yield is a critical factor for any cultivator. While there are many ways to increase yield, some can be quite aggressive and stressful for the plant, potentially compromising its health in the long run. LST, with its gentle approach, allows for an increase in yield without causing undue stress. By optimizing light exposure to a greater number of buds, LST ensures each bud has the potential to grow to its maximum size.

3. Control Over Plant Height and Structure

For many cultivators, especially those with indoor setups or limited space, managing plant height is crucial. LST provides growers with the ability to control and direct plant growth horizontally rather than vertically, making it an invaluable tool for space management. This control isn’t just limited to height; LST also allows cultivators to shape the overall structure of the plant, ensuring optimal space utilization and aesthetics.

Step-by-Step Guide to LST

Low Stress Training, though a gentle process, requires precise steps to be effectively implemented. Let’s delve into a detailed guide that ensures you maximize the benefits of LST:

1. When to Start LST in the Plant’s Life Cycle

Timing is vital. Begin LST when your plant has at least 3-4 nodes (sets of leaves). This ensures the plant is established enough to handle gentle manipulation but still young enough to be flexible. For most cannabis plants, this typically falls around the 3-4 week mark from germination.

2. Tools Needed

Before you start, gather the necessary tools:

Soft Tie or Garden Tie: These are flexible, and soft, and can be adjusted as the plant grows.
Garden Wire or Twist Ties: Useful for more precise adjustments.
Garden Stakes or Hooks: To help anchor the plant branches in place.
Gloves: Optional, but can be helpful to avoid any unintentional damage to the plant or for personal protection against sap.

3. Techniques: Bending, Tying Down, and Securing

Bending: Start by gently bending the taller branches towards the grow medium. It’s essential to bend slowly to avoid snapping them. The aim is to make the plant’s canopy as even as possible.
Tying Down: Once you’ve bent the branch to the desired position, use your ties to secure it to your container’s edge or your garden stake. The goal is not to strangle, but to guide.
Securing: As your plant grows and develops more branches, repeat the bending and tying process. Make sure the ties aren’t too tight, giving the branches room for growth.

4. Monitoring and Adjusting as the Plant Grows

Consistent observation is key. As your plant grows, some branches may attempt to revert to their original upward growth. Periodically adjust ties and bend new growth to maintain an even canopy. Also, be on the lookout for any signs of stress or damage, adjusting your ties if they’re too tight or if a branch shows signs of undue strain.

Combining LST with Other Techniques

Cannabis cultivation, like any form of gardening, isn’t restricted to a single technique. For those aiming to get the best out of their plants, combining methods can bring about enhanced results. Let’s explore how Low Stress Training can synergize with other popular techniques:

Synergizing LST with Techniques

Topping: This technique involves removing the top of the plant to promote the growth of two main colas instead of one. By combining topping with LST, you can further control the direction of these colas, optimizing space and light exposure.
Supercropping: Supercropping involves carefully pinching and bending stems to make them stronger. Once supercropped, stems can be directed using LST, guiding the growth direction more efficiently.
FIMing: Similar to topping, FIMing (F*ck I Missed) increases the number of main colas. By integrating FIMing with LST, you gain greater control over the plant’s overall structure and light penetration.
Defoliation: This is the selective removal of leaves to allow light to penetrate deeper into the canopy. After defoliating, LST can be even more effective as the bending and securing of branches will expose more bud sites.

How to Ensure You Don’t Overstress the Plant

Combining techniques can boost your plant’s potential, but there’s a risk of overstressing. Here’s how to ensure your plant stays healthy:

Stagger Techniques: Avoid implementing multiple training techniques simultaneously. Give your plant time to recover from one before starting another.
Observe and Respond: Monitor your plant closely for signs of stress, such as yellowing leaves, drooping, or stunted growth. Adjust or ease up on training if you notice any adverse reactions.
Be Gentle: While plants are resilient, they can be sensitive. Whether bending for LST or pinching for supercropping, always be as gentle as possible.
Educate Yourself: Before combining techniques, familiarize yourself with each one. Understanding their individual effects will better inform how and when to combine them.

Benefits of LST in Different Growth Mediums

Low Stress Training (LST) offers a host of benefits regardless of the medium in which your plant grows. However, different growth mediums can have variations in how they respond to this technique. Here’s a deeper look into LST’s effects across different mediums.

Soil vs. Hydroponics: How LST Effects Might Vary

Soil:
- Natural Buffer: Soil naturally provides a buffer against sudden changes, ensuring that plants have a slower and steadier response to LST adjustments.
- Root Growth: LST can enhance sunlight exposure to the soil, potentially benefiting root health and growth indirectly.
- Flexibility: Soil offers a bit more forgiveness. If a branch is bent too far or a minor mistake is made during LST, the stable environment of the soil can often help the plant recover more efficiently.
Hydroponics:
- Rapid Response: Plants in hydroponic systems often respond faster to training due to the direct nutrient uptake. This can mean quicker visible results from LST but also necessitates careful monitoring.
- Root Health: In hydroponic systems, root health is paramount. While LST primarily affects the plant’s aerial parts, ensuring the system remains undisturbed is essential.
- Adjustments: Hydroponic systems might require more frequent LST adjustments due to the potential for faster growth rates.

Adjusting LST Based on Grow Medium Constraints

Soil:
- Since soil-grown plants might grow at a steadier pace, the intervals between LST adjustments can be slightly longer.
- Ensure that ties or anchors used in LST don’t overly compact the soil, which could affect root health and water drainage.
Hydroponics:
- Be wary of the equipment. When securing branches, ensure that ties or stakes don’t damage or disturb the hydroponic system, especially the tubing or the water/nutrient flow.
- Given the direct nutrient access in hydroponics, plants might grow faster, demanding more frequent LST checks and adjustments.

Common Mistakes & Solutions in LST

While Low Stress Training is one of the gentler cultivation techniques, it’s still possible to make mistakes. Let’s explore some of the most common missteps and their solutions to ensure your LST journey remains effective and hassle-free.

Overtraining or Injuring the Plant

Mistake: Overzealous bending or frequent adjustments can lead to unintentional injuries like snapped branches.
Solution: Always handle the plant with care, bending stems slowly and patiently. If you accidentally snap a branch, don’t panic. Secure the broken part with tape or a soft tie, and often, the plant will heal itself in time.

Inadequate Equipment Choice

Mistake: Using hard ties, string, or subpar stakes can damage plant tissue, cause undue stress, or fail to hold the plant in the desired position.
Solution: Opt for soft ties or garden ties, which are gentle on plants and can be adjusted as the plant grows. Ensure stakes or anchors are of good quality and won’t harm the plant or its root system.

Neglecting to Monitor Post-Training

Mistake: Once LST is done, some growers might neglect regular check-ups, missing vital signs of stress or growth changes.
Solution: Post-training monitoring is crucial. Regularly inspect your plant to ensure that all parts continue to receive adequate light. Watch out for signs of stress or damage and make adjustments as needed. Remember, LST is a dynamic process, and the plant’s needs might change as it grows.

Conclusion

Low Stress Training (LST) is more than just a cultivation technique; it’s a gateway to unlocking a plant’s full potential. By understanding and implementing LST, growers can significantly enhance growth and yield. However, the true power of LST lies in its adaptability. Each garden and grower is unique, and while LST provides a foundational method, its real magic is witnessed when tailored to specific needs and challenges. For both novices and experts, embracing LST can pave the way for healthier plants and richer harvests, showcasing the genuine care and commitment behind every thriving garden.