What Is LST in Cannabis Growing? Low Stress Training Guide

What LST Means in Cannabis Growing

LST stands for low stress training. It is a set of bending and tying techniques that shape a cannabis plant without cutting it. You pull tall stems down and outward, tie them to the pot rim or a trellis, and let the lower branches rise into the light. The plant stays intact, so it recovers fast and keeps growing through the whole process.

low stress training cannabis step by step

Growers use LST to flatten the canopy, spread light across more bud sites, and control height in tents and small rooms. It pairs well with topping and defoliation, but it works on its own too.

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Why Bending Changes the Plant

Cannabis grows with apical dominance. The shoot tip produces auxin, a hormone that travels down the stem and suppresses the buds below it. That is why an untrained plant turns into one tall cola with small side branches.

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When you bend the main stem below the height of the side shoots, auxin distribution shifts. The lower branches stop being suppressed, stretch upward, and become their own tops. The result is a wide, level canopy where every cola receives similar light intensity instead of one top hogging the lamp.

When to Start

Start once the plant has four to six nodes and a flexible main stem. In soil or coco this usually lands around week three to four of veg. Stems harden with age, so early bending takes less force and causes less risk of a snap.

Prerequisites

• A healthy plant in active vegetative growth, not a stressed or sick one
• A pot with a rim or grommets, or a scrog net above the canopy
• Soft plant ties, coated wire, or garden twine
• Clean hands and a stable light schedule

How to LST a Cannabis Plant

1. Water the plant a few hours before training so the stems bend instead of cracking.
2. Choose the anchor point on the pot rim directly opposite the direction you want the stem to fall.
3. Bend the main stem down and out with two fingers, supporting the stem below the bend.
4. Loop the tie around the stem at a soft angle where it meets a node, never on a bare thin section.
5. Anchor the tie to the rim and leave a half inch of slack so the stem can thicken.
6. Push the newest side shoots outward from the center of the pot with your fingers.
7. Check ties every two to three days and loosen any that dig into the stem.
8. Keep bending new growth flat through the stretch phase, then stop once flowers set.

Mistakes That Cost Yield

• Bending a dry, woody stem and snapping it
• Tying too tight and cutting off the plant's internal flow
• Bending only once and letting one top regain dominance
• Training a flowering plant hard in late bloom, which stalls bud development
• Leaving the canopy flat but crowded, so lower leaves get no air

LST vs HST

High stress training means cutting: topping, fimming, super cropping. Those methods remove or break tissue, and the plant needs recovery time. LST never breaks the skin. You can train daily with almost no downtime, which makes it the better choice for autoflowers and for growers who want steady, low risk canopy control.

Most indoor setups get the best result from a mix: top once for more main branches, then use LST to keep every branch at the same height.