Every cannabis plant has a default growth pattern — a single dominant main cola stretching upward toward the light while lower branches compete in its shadow. Left untrained, this apical dominance produces a tall, Christmas tree-shaped plant where the top bud site receives optimal light and the rest receive progressively less. The result is an uneven canopy where yield potential is heavily concentrated at the top and largely wasted below.
Cannabis LST — Low Stress Training — solves this fundamental yield inefficiency through a simple but transformative principle: bend the plant rather than cut it. By gently redirecting growth horizontally rather than vertically, cannabis LST disrupts apical dominance, exposes multiple bud sites to equal light intensity, and signals the plant to produce multiple dominant colas rather than one. The outcome is a plant that is shorter, wider, more productive, and significantly easier to manage — all without the stress response that cutting and defoliation techniques trigger.
At Space Trees Chiang Mai, cannabis LST is a core component of our living soil cultivation programme. This complete guide covers everything you need to know — the science behind why it works, the tools required, the step-by-step technique, how LST interacts with living soil cultivation, common mistakes, and the advanced variations worth exploring once the fundamentals are mastered.
Table of Contents
- What Is Cannabis LST and Why Does It Work?
- LST vs High Stress Training: Key Differences
- Tools and Equipment
- When to Start Cannabis LST
- Step-by-Step Cannabis LST Guide
- Cannabis LST and Living Soil
- Advanced LST Variations
- Common Cannabis LST Mistakes
- LST for Different Strain Types
- Cannabis LST at Space Trees Thailand
- FAQ
What Is Cannabis LST and Why Does It Work?
Cannabis LST is a training technique that involves gently bending and securing the stems and branches of cannabis plants to redirect growth, create an even canopy, and maximise the number of bud sites receiving direct light. The “low stress” designation distinguishes it from techniques that involve cutting, pinching, or otherwise wounding the plant — cannabis LST achieves its results through manipulation rather than injury.
The Science: Apical Dominance and Auxin Redistribution
To understand why cannabis LST works, you need to understand apical dominance — the biological mechanism that drives the plant’s natural vertical growth pattern.
The growing tip (apical meristem) of a cannabis plant produces auxin — a plant hormone that suppresses the development of lateral shoots below it. This auxin flows downward through the plant, maintaining the dominance of the main stem and limiting the growth of side branches. The result is the characteristic tall, single-cola growth pattern of an untrained cannabis plant.
When you bend the main stem in cannabis LST, you disrupt the downward auxin flow. Auxin pools at the bend point rather than flowing uniformly downward — and lateral shoots below the bend, suddenly released from hormonal suppression, begin to grow toward the light with dramatically increased vigour. The plant, perceiving multiple upward-growing tips rather than one, distributes its growth energy more evenly across the entire canopy.
The practical result is a plant with multiple equally dominant bud sites — a flat, wide canopy where every flower site receives the same quality of light rather than progressively degraded light as you move down the plant.
LST vs High Stress Training: Key Differences
Cannabis LST exists within a broader spectrum of cannabis training techniques. Understanding where it sits relative to high stress methods helps growers choose the right approach for their plants and growing situation.
Low Stress Training (LST)
- Method: Bending and securing stems without cutting
- Stress level: Minimal — the plant does not enter a stress/recovery cycle
- Recovery time: None required — growth continues immediately
- Best for: All growers, all strains, all growing environments
- Risk: Very low — minimal risk of plant damage
- Living soil compatibility: Excellent — no disruption to root zone or biological activity
High Stress Training (HST)
HST techniques — including topping, fimming, super cropping, and defoliation — involve cutting or significantly stressing plant tissue. They can produce dramatic canopy restructuring but require the plant to enter a recovery period before resuming growth.
Topping removes the apical growing tip entirely, forcing the plant to develop two dominant colas. More dramatic canopy change but requires 5–7 days of recovery.
Super Cropping involves pinching and bending stems until the interior tissue breaks without the skin tearing. Creates knuckle-like reinforcement nodes but is riskier than cannabis LST.
The Space Trees approach: In a living soil environment, we favour cannabis LST as the primary training method — it produces excellent canopy development without the recovery periods or stress responses that high stress techniques create. In living soil, the plant’s biological energy is best invested in growth and terpene development rather than wound response.
Tools and Equipment
Cannabis LST requires minimal equipment — one of its most accessible qualities as a training technique.
Essential tools:
Soft plant ties — the most important tool. Garden tie tape, soft silicone ties, or fabric-coated wire are ideal. Avoid hard wire or string that can cut into stems as the plant grows. Ties should be loose enough to allow some stem expansion.
Bamboo stakes or dowels — used to anchor ties and redirect branch growth. Should be long enough to stake into the soil and sturdy enough to hold branch tension.
Small clips or carabiners — some growers prefer clips over ties for easier adjustment and removal. Available from hydroponic supply stores.
Pot with anchor points — many purpose-designed training pots have holes around the rim for attaching ties directly to the container. Otherwise, bamboo stakes inserted into the soil provide anchor points.
Optional tools for advanced techniques:
SCROG net — a horizontal net stretched across the growing space that supports and directs canopy growth. Essential for Screen of Green (SCROG) — an advanced cannabis LST variation.
Trellis netting — vertical netting that supports heavily trained canopies during flowering.
When to Start Cannabis LST
Timing is one of the most important variables in successful cannabis LST. The optimal window is specific and missing it reduces the technique’s effectiveness.
Optimal Start Point: Early to Mid Vegetative Stage
Begin cannabis LST when the plant has developed 4–6 nodes — typically 2–3 weeks into vegetative growth from transplant. At this stage:
- Stems are flexible enough to bend without snapping
- The plant is large enough to have meaningful branch structure to work with
- Apical dominance is established and disrupting it produces the maximum lateral growth response
- The plant has sufficient root development to support the increased growth demands
Too early: Seedlings and very young plants have limited stem flexibility and insufficient node development. Cannabis LST started too early produces minimal canopy benefit.
Too late: Older vegetative plants develop thicker, less flexible stems that are harder to bend safely and are more likely to snap or crack at sharp angles. Starting late in veg is still beneficial but requires more careful, gradual manipulation.
Continuing into Early Flower
Cannabis LST can be continued into the first 2–3 weeks of flowering — often called the “stretch phase” when the plant rapidly increases in height. During this period, continued gentle training maintains canopy evenness as bud sites develop. After week 3 of flower, stems become less flexible and LST is generally discontinued.
Step-by-Step Cannabis LST Guide
Step 1 — Assess the Plant
Before beginning cannabis LST, examine the plant’s overall structure. Identify the main stem (the apical shoot), the lateral branches, and the direction of natural growth. Choose which direction you will bend the main stem — typically toward the outside edge of the pot.
Step 2 — Prepare Your Ties and Anchor Points
Set up bamboo stakes or identify anchor points around the pot rim. Cut ties to appropriate lengths — longer for the main stem, shorter for lateral branches. Have everything ready before you start manipulating the plant.
Step 3 — Water the Plant Before Training
A well-hydrated plant has more flexible stems than a thirsty one. Water your plant a few hours before beginning cannabis LST to maximise stem pliability and reduce snap risk.
Step 4 — Begin with the Main Stem
Gently and slowly bend the main stem toward your chosen anchor point — aiming for a roughly 90-degree angle relative to its original vertical position. Move slowly and feel for resistance. The stem should bend without cracking. If you feel significant resistance, ease off and try again more gradually over a few sessions.
Step 5 — Secure the Stem
Once bent to the desired angle, secure the stem to your anchor point with a soft tie. The tie should hold the stem in place without cutting into it — loop it loosely so the stem can expand as it grows. The bent tip should now be pointing horizontally or slightly upward toward the light.
Step 6 — Address Lateral Branches
As the main stem is secured horizontally, lateral branches will begin reaching upward. Over the following days, gently bend these branches outward and secure them — working toward a radial pattern where branches spread evenly in all directions from the container centre.
Step 7 — Monitor and Adjust
Check your cannabis LST setup daily in the first week. The plant will actively grow toward the light — new growth from the bent main stem will turn upward rapidly. As new shoots develop and grow, continue securing and spreading them to maintain an even canopy.
Step 8 — Transition to Flower
Once your training has produced a wide, even canopy with multiple equally-developed bud sites, the plant is ready to transition to the 12/12 light cycle to initiate flowering. The level canopy you have created through cannabis LST will produce a uniform flush of bud development across all sites simultaneously.
Cannabis LST and Living Soil
Cannabis LST and living soil cultivation are highly compatible — in fact, LST is particularly well-suited to the living soil environment for several reasons.
No Root Zone Disruption
Unlike high stress techniques that trigger wound-response chemistry throughout the plant — potentially redirecting biological resources away from root zone activity — cannabis LST produces no stress response. The plant continues its normal biological activity, including mycorrhizal network development and root zone nutrient uptake, without interruption.
Horizontal Canopy and Light Efficiency
Living soil growing environments typically use high-quality LED or HID lighting optimised for flat, horizontal canopy illumination. Cannabis LST‘s horizontal canopy development perfectly matches the light distribution pattern of these systems — maximising photon capture across the entire canopy surface.
Terpene Development
Because cannabis LST does not trigger a stress response, the plant continues investing biological energy into terpene development throughout the training period. High stress techniques can temporarily reduce terpene production while the plant focuses on wound response. This distinction matters enormously in a living soil environment where the goal is maximum terpene expression. For the full terpene science: Cannabis Terpenes: The Ultimate Guide
Companion Plant Compatibility
In a living soil grow room with companion plants between cannabis plants, the wide, horizontal canopy produced by cannabis LST can be designed to avoid crowding companion plants — maintaining the beneficial insect habitat that forms part of the living soil IPM system. Read more: Cannabis IPM: The Complete Guide
Advanced LST Variations
Once the fundamentals of cannabis LST are mastered, several advanced variations offer additional canopy control and yield potential.
Screen of Green (SCROG)
The most widely used advanced cannabis LST technique. A horizontal screen or net is positioned above the plants, and branches are woven through the screen as they grow — creating an exceptionally even canopy supported by the screen structure. SCROG maximises the total bud-producing surface area and is particularly effective in indoor controlled environments with flat canopy lighting.
Mainlining (Manifolding)
A more structured form of cannabis LST that creates a symmetrical plant architecture from a central manifold point — typically established by topping the plant at the third node and then training the two resulting branches symmetrically. Mainlining combined with LST produces plants with 8, 16, or 32 equally dominant bud sites — maximising yield consistency.
Tie-Down with SCROG Combination
Combining basic cannabis LST tie-down technique with SCROG netting produces the most even canopy possible in an indoor environment — using tie-downs to establish the initial horizontal spread and the SCROG net to support and maintain the canopy through flowering.
Lollipopping
Not strictly an LST technique but frequently combined with it — lollipopping involves removing lower growth that will not receive adequate light under the trained canopy. This redirects biological energy to upper bud sites, improving the quality and size of the primary colas developed through cannabis LST.
Common Cannabis LST Mistakes
Starting Too Late
Attempting cannabis LST on plants with thick, mature stems risks snapping rather than bending. If stems are too stiff to bend safely, consider super cropping instead or accept a less dramatic training result with gentler, more gradual manipulation.
Ties That Are Too Tight
Ties that constrict stem growth as the plant develops cause damage and can girdle branches — cutting off vascular flow. Always use soft ties and check them every few days, loosening as needed to accommodate stem expansion.
Training Too Aggressively
Bending stems sharply to extreme angles in one session risks cracking or snapping. Cannabis LST should be gradual — bend to the point of resistance, secure, and allow the plant to adjust before continuing. Multiple gentle sessions produce better results than one aggressive one.
Neglecting Lateral Branch Training
Many beginners focus only on the main stem and neglect the lateral branches that emerge after initial training. Complete cannabis LST requires ongoing management of all major branches — not just the original main stem.
Training into Flower Too Long
Continuing cannabis LST past week 3 of flower on plants with hardening stems risks stem damage at a critical bud development period. Finish training by early flower and allow the plant to focus its energy on bud production.
LST for Different Strain Types
Cannabis LST is effective across all strain types but produces different results depending on genetics.
Indica-dominant strains — typically compact with short internodal spacing. LST opens up the dense canopy, improving light penetration and airflow. The naturally bushy growth pattern of indica strains means LST has significant impact even with moderate training.
Sativa-dominant strains — naturally wide and branchy, with longer internodal spacing. LST tames the vigorous lateral growth of sativa genetics, preventing canopy crowding while maintaining the multiple bud site development these strains naturally tend toward.
Autoflowering strains — require modified cannabis LST due to their compressed life cycle. Begin training within the first 2 weeks of vegetative growth, use very gentle manipulation, and stop well before the transition to flower. Autoflowers cannot recover from overtraining in the way photoperiod plants can.
At Space Trees, our genetics — including Ethos Genetics, LIT Farms, and Doja Exclusive cultivars — are all photoperiod plants specifically selected for robust vegetative vigour that responds well to cannabis LST. The Wizard Trees cut of RS-11 used in our Rainbow Marker, for instance, responds exceptionally well to LST’s lateral branch development — the wide structure that results from training matches the genetics’ natural tendency toward lateral branching and heavy resin production across the full canopy.
Cannabis LST at Space Trees Thailand
Cannabis LST is standard practice in every grow cycle at Space Trees Chiang Mai — used alongside living soil cultivation to produce the even, productive canopies that generate the consistent quality our customers experience across every strain on the menu.
Our cultivation team, led by Sam Walker with over 20 years of cannabis cultivation experience, applies cannabis LST principles to every plant from early veg through the stretch phase of flowering — adapting the technique to each strain’s specific growth characteristics and the requirements of our living soil indoor environment.
The combination of cannabis LST, mycorrhizal living soil cultivation, and careful pheno-selected genetics is what produces the consistent bag appeal, terpene expression, and bud density that Space Trees is known for. For the full story of how each element works together, read:
- What Is Living Soil Cannabis?
- Mycorrhizae Cannabis: Nature’s Root Network
- Cannabis Pheno Hunting: Finding Elite Genetics
- Cannabis Cloning: The Complete Guide
Frequently Asked Questions
What is cannabis LST?
Cannabis LST — Low Stress Training — is a cultivation technique that involves gently bending and securing cannabis stems and branches to disrupt apical dominance, create an even horizontal canopy, and expose multiple bud sites to equal light intensity. Unlike high stress techniques, LST achieves canopy restructuring without cutting or wounding the plant.
When should I start cannabis LST?
Begin cannabis LST when the plant has 4–6 nodes — typically 2–3 weeks into the vegetative stage from transplant. At this point stems are flexible enough to bend safely and the plant has sufficient structure to respond meaningfully to training. Continue through the vegetative stage and into the first 2–3 weeks of flower.
Does cannabis LST increase yield?
Yes — cannabis LST consistently increases yield by exposing more bud sites to direct light. A flat, even canopy produced through LST develops multiple equally dominant flower sites rather than concentrating yield in a single main cola. Most growers report 20–40% yield increases compared to untrained equivalents under the same growing conditions.
Is cannabis LST suitable for living soil grows?
Cannabis LST is particularly well-suited to living soil cultivation. It produces no stress response that would redirect biological energy away from root zone activity and terpene development. The horizontal canopy it creates also maximises the efficiency of the high-quality lighting used in indoor living soil environments.
What is the difference between LST and SCROG?
Cannabis LST is the base technique — bending and securing stems. SCROG (Screen of Green) is an advanced LST variation that uses a horizontal net to support and organise the trained canopy. SCROG produces an exceptionally even canopy and is particularly effective in indoor grow rooms with flat LED lighting.
Can I use LST on autoflowering cannabis strains?
Yes, but with modifications. Autoflowering cannabis strains have a compressed life cycle with limited vegetative time. Begin very gentle LST within the first 2 weeks of growth and use minimal manipulation — autoflowers cannot recover from overtraining the way photoperiod plants can. Stop all training before the plant begins to show early flower signs.
Does Space Trees use LST on their plants?
Yes — cannabis LST is standard practice across all Space Trees grow cycles in Chiang Mai. Applied from early veg through the flowering stretch phase in combination with living soil cultivation and carefully selected genetics, LST is one of the key practices behind the consistent bag appeal and canopy quality that Space Trees produces.
Last updated: 2026 | Written by Sam Walker, Space Trees cultivation specialist with 20+ years of cannabis growing experience. For educational purposes. All cultivation practices should comply with local laws and regulations.
