# Sulfur burner

> A heated vessel that vaporises elemental sulfur to suppress powdery mildew and mites in veg rooms; it carries fire, gas and timing risks and is never used in flower.

- Canonical: https://genetixbay.com/knowledge/glossary/sulfur-burner.html
- Also written: sulphur burner, sulfur vaporizer, sulphur vaporiser, sulfur evaporator, vaporised sulfur, elemental sulfur
- Glossary category: Pests and diseases · 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"

A sulfur burner, more accurately a [sulfur](https://genetixbay.com/knowledge/glossary/sulfur.md) vaporiser, is an electric heater with a small dish that warms elemental sulfur until it sublimes and drifts through a room, settling as a fine film on leaves. That film suppresses [powdery mildew](https://genetixbay.com/knowledge/glossary/powdery-mildew.md) and some [mites](https://genetixbay.com/knowledge/glossary/two-spotted-spider-mite.md). Elemental sulfur is a widely used, long-established fungicide and acaricide active ingredient.

## In practice

Growers run vaporisers in veg and mother rooms, typically during the dark period and with nobody present. Safety and timing points:

- If the sulfur overheats or ignites, it forms sulfur dioxide, a toxic, choking gas, so the unit must stay within its designed temperature and away from anything flammable.
- Sulfur dust and vapour irritate eyes and lungs; keep people and pets out.
- Sulfur and oil sprays near each other in time can scorch leaves.
- Vaporising in flower taints aroma and leaves deposits on buds; stop well before flower.

Whether sulfur use is permitted on cannabis, and on what terms, depends on product registration and local rules. Check what is registered for cannabis locally and follow the label.

## Don't confuse with

- **Wettable sulfur sprays**: the same active, applied in water.
- **Lime sulfur**: calcium polysulfide, a harsher product.
- **Sulfur as a nutrient**: [sulfate](https://genetixbay.com/knowledge/glossary/sulfate.md) in feed, an essential plant element.

## Related terms

[Powdery mildew](https://genetixbay.com/knowledge/glossary/powdery-mildew.md), [Hemp russet mite](https://genetixbay.com/knowledge/glossary/hemp-russet-mite.md), [Horticultural oil](https://genetixbay.com/knowledge/glossary/horticultural-oil.md), [Pre-harvest interval](https://genetixbay.com/knowledge/glossary/pre-harvest-interval.md), [Contact vs systemic](https://genetixbay.com/knowledge/glossary/contact-vs-systemic.md)

## Read more

- [Powdery mildew in cannabis](https://genetixbay.com/knowledge/diseases/powdery-mildew.md)

## Sources

1. PNW Plant Disease Management Handbook. Hemp (Cannabis sativa) - Powdery Mildew. https://pnwhandbooks.org/plantdisease/host-disease/hemp-cannabis-sativa-powdery-mildew