# Plant density

> Plant density is the number of plants per unit of canopy area; more plants raise yield per area up to a point but shorten veg and reduce uniformity.

- Canonical: https://genetixbay.com/knowledge/glossary/plant-density.html
- Also written: planting density, plants per square metre, plants per square meter, plants per m², stocking density, plant spacing
- Glossary category: Cultivation and training · Evidence: Supported
- Status: Draft: awaiting expert review · Updated: 2026-10-31
- Licence: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/), attribute "GenetixBay cannabis glossary"

Plant density is how many plants occupy a given area, usually given as plants per square metre (1 m² = 10.76 ft²). It interacts with [veg time](https://genetixbay.com/knowledge/glossary/veg-time.md): few large plants and many small plants can fill the same canopy, the first by growing longer, the second by numbers.

## In practice

Typical ranges: one to four plants per m² for trained [SCROG](https://genetixbay.com/knowledge/glossary/scrog.md) or mainlined plants; about 9-20 per m² for [sea of green](https://genetixbay.com/knowledge/glossary/sog.md) clones. In a study of drug-type [medical cannabis](https://genetixbay.com/knowledge/glossary/medical-vs-adult-use.md), higher density increased yield per area while reducing yield per plant and lowering the uniformity of [cannabinoid](https://genetixbay.com/knowledge/glossary/cannabinoid.md) content between plants. Higher density also means more clones, more stems, and denser air under the canopy, which raises humidity and mould risk.

For home growers the deciding factor is often the law: many places cap plant numbers, so fewer, larger, well-trained plants make sense. Check local rules.

## Don't confuse with

- **Plant count limits**: a legal cap on the number of plants; covered as a legal term.
- **Canopy area**: the area itself; density divides [plant count](https://genetixbay.com/knowledge/glossary/plant-count-limit.md) by it.

## Related terms

[SOG](https://genetixbay.com/knowledge/glossary/sog.md), [SCROG](https://genetixbay.com/knowledge/glossary/scrog.md), [Yield](https://genetixbay.com/knowledge/glossary/yield.md), [Canopy](https://genetixbay.com/knowledge/glossary/canopy.md), [Veg time](https://genetixbay.com/knowledge/glossary/veg-time.md)

## Read more

- [SOG: sea of green](https://genetixbay.com/knowledge/training/sog.md)

## Sources

1. Danziger N, Bernstein N, 2022. Too dense or not too dense: higher planting density reduces cannabinoid uniformity but increases yield/area in drug-type medical cannabis. Frontiers in Plant Science 13:713481. https://doi.org/10.3389/fpls.2022.713481
2. Backer R, Schwinghamer T, Rosenbaum P, et al., 2019. Closing the yield gap for cannabis: a meta-analysis of factors determining cannabis yield. Frontiers in Plant Science 10:495. https://doi.org/10.3389/fpls.2019.00495