# Burping

> Briefly opening sealed curing jars to release moist air and let fresh air in, so moisture keeps declining slowly during the cure.

- Canonical: https://genetixbay.com/knowledge/glossary/burping.html
- Also written: burp, burping jars, burp the jars, jar burping, airing jars
- Glossary category: Harvest, drying and curing · Evidence: Grower practice
- 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"

Burping is opening [curing jars](https://genetixbay.com/knowledge/glossary/curing-jar.md) for a short time, typically a few minutes to tens of minutes, to swap the humid air in the headspace for room air. It lets moisture that has migrated from the bud cores to the surface escape, so the cure moves gradually toward the target [water activity](https://genetixbay.com/knowledge/glossary/water-activity.md) without the jar staying too wet.

## In practice

A common schedule (Grower practice):
- **Week 1**: once or twice a day, guided by equilibrated [jar RH](https://genetixbay.com/knowledge/glossary/equilibrium-relative-humidity.md).
- **Week 2**: every day or two.
- **Weeks 3-4**: once or twice a week, then mostly sealed.

Let the hygrometer guide you rather than the calendar. If a jar equilibrates above about 65% [RH](https://genetixbay.com/knowledge/glossary/relative-humidity.md), burp longer or take the buds out to air on a tray for an hour or so. If it drops below about 55%, keep it closed. House approach: if you need to add moisture back, put a fresh bud in the jar rather than a [humidity pack](https://genetixbay.com/knowledge/glossary/humidity-pack.md).

When opening, smell the jar. A sharp ammonia or musty smell means too wet and possible microbial growth; spread the buds out and inspect for mould.

## Don't confuse with

- **Curing**: the whole process; burping is one step in it.
- **Venting a grow room**: air exchange in cultivation.
- **Humidity packs**: try to hold RH fixed, which is the opposite of a slow decline.

## Related terms

[Curing](https://genetixbay.com/knowledge/glossary/curing.md), [Equilibrium relative humidity](https://genetixbay.com/knowledge/glossary/equilibrium-relative-humidity.md), [Water activity](https://genetixbay.com/knowledge/glossary/water-activity.md), [Humidity pack](https://genetixbay.com/knowledge/glossary/humidity-pack.md)

## Read more

- [Curing and burping: jars, humidity and how long](https://genetixbay.com/knowledge/harvest-cure/curing-burping.md)

## Sources

1. ASTM D8197. Standard Specification for Maintaining Acceptable Water Activity (aw) Range (0.55 to 0.65) for Dry Cannabis Flower. ASTM International. https://store.astm.org/d8197-22.html