Training methods compared
| Method | Stress | What it does | When | Autos? |
|---|---|---|---|---|
| LST (tie-down) | Low | Flattens canopy, exposes bud sites, no recovery pause | Early veg onward | ✅ The auto-safe option |
| Topping | High | Cuts the main tip → 2 colas, bushier plant | 3–5 nodes, veg only | ⚠️ Only very vigorous autos, very early |
| FIM | High | Partial pinch → 3–4+ colas, messier, faster recovery than topping | Veg | ⚠️ Same caveat |
| SCROG (screen) | Low-med | Weave through a net → even canopy, best light use | Veg → early flower | ✅ With LST only |
| Defoliation | Med | Removes fan leaves blocking bud sites/airflow | Sparingly; classic passes day 1 + 21 of flower | ⚠️ Light touch |
The rule behind every method: stress must pay for itself in light distribution. Photoperiods can wait out recovery; autoflowers cannot — every stressed day is yield gone.
Common questions
Which training method should I use?
Low-stress training and SCROG shape the canopy with little recovery cost. Topping and FIM redistribute growth but cost recovery days. On autoflowers, prefer low-stress methods — they run on age, so lost days cannot be made up in veg.
Does defoliation increase yield?
The evidence is mixed and does not clearly support it. Recent indoor trials found no substantial improvement in floral biomass or CBD yield from defoliation. Where benefits are documented, they are about improving light penetration to lower buds and making the plant more uniform — not raising the total.
Why are lower buds always weaker?
Light. Bottom inflorescences have been measured up to 90% lower in cannabinoid concentration than the top, and the driver is light penetration, not distance from the roots.
Is it better to grow more plants or train fewer?
Density does more than training for yield per square metre — going from 1 to 2 plants/m² raised yield per area 28–44% in one study, even though yield per plant fell.
Sources: Danziger & Bernstein 2021, Plants — light penetration drives lower-bud potency · Danziger & Bernstein 2022, Frontiers in Plant Science — density lifted yield per m² by 28–44% · Crispim Massuela et al. 2022, Plants — topping added biomass, not significant CBD yield · Salachas et al. 2026, J. Cannabis Research — topping above the 4th node
- Trellis netting — the cheapest yield upgrade in a tent — SCROG without the guesswork
- Plant ties / soft wire — low-stress training without snapping stems
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Keep reading
- When to flip and what the stretch does
- Why autoflowers need a lighter touch
- Judging readiness at the end
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