# Zinc

> Zinc (Zn) is a micronutrient needed for auxin production and many enzymes; deficiency gives small, twisted new leaves and shortened internodes.

- Canonical: https://genetixbay.com/knowledge/glossary/zinc.html
- Also written: Zn, Zn2+, zinc deficiency
- Glossary category: Nutrients · Evidence: Established
- 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"

Zinc is a [micronutrient](https://genetixbay.com/knowledge/glossary/micronutrient.md) absorbed as Zn2+. It is a cofactor for many enzymes and is needed for making the growth hormone auxin, which is why shortage shows as stunted, compressed growth. It is only moderately mobile in the plant.

## In practice

[Deficiency](https://genetixbay.com/knowledge/glossary/nutrient-deficiency.md) produces small, narrow, twisted or wrinkled new leaves, [interveinal chlorosis](https://genetixbay.com/knowledge/glossary/interveinal-chlorosis.md) near the tips and very [short internodes](https://genetixbay.com/knowledge/glossary/node-stacking.md) ("rosetting"). High phosphorus and high [pH](https://genetixbay.com/knowledge/glossary/ph.md) both reduce zinc availability, so a heavy bloom-booster regime is a classic trigger. Hydro feeds usually carry somewhere around 0.1-0.5 mg/L (ppm) Zn. [Zinc sulfate](https://genetixbay.com/knowledge/glossary/zinc-sulfate.md) or a [chelate](https://genetixbay.com/knowledge/glossary/chelate.md) supplies it; galvanised pipes and fittings can leach extra zinc.

## Don't confuse with

- **Heat or light stress**: can also curl new growth, but without the short internodes.
- **Broad or russet mites**: twisted, glossy new growth with no nutrient pattern; check with a loupe.
- **Manganese deficiency**: mottling without the leaf distortion.

## Myth check

Zinc problems in flower are often caused rather than cured by high-P additives. See [bloom boosters](https://genetixbay.com/knowledge/nutrients/bloom-boosters.md) and [nutrient antagonism](https://genetixbay.com/knowledge/nutrients/nutrient-antagonism.md).

## Related terms

[Micronutrient](https://genetixbay.com/knowledge/glossary/micronutrient.md), [Zinc sulfate](https://genetixbay.com/knowledge/glossary/zinc-sulfate.md), [Phosphorus](https://genetixbay.com/knowledge/glossary/phosphorus.md), [Nutrient antagonism](https://genetixbay.com/knowledge/glossary/nutrient-antagonism.md), [Chelate](https://genetixbay.com/knowledge/glossary/chelate.md)

## Read more

- [Zinc (Zn) in cannabis: small leaves, margin burn and the phosphorus link](https://genetixbay.com/knowledge/nutrients/zinc.md)

## Sources

1. Marschner P (ed.). 2012. Marschner's Mineral Nutrition of Higher Plants, 3rd ed. Academic Press. https://doi.org/10.1016/C2009-0-63043-9
2. Cockson P, Landis H, Smith T, Hicks K, Whipker BE. 2019. Characterization of nutrient disorders of Cannabis sativa. Applied Sciences 9(20):4432. https://doi.org/10.3390/app9204432