# 60/60 rule

> A drying rule of thumb: dry cannabis at about 60 °F (15.5 °C) and 60% relative humidity so buds dry slowly over roughly 10-14 days.

- Canonical: https://genetixbay.com/knowledge/glossary/60-60-rule.html
- Also written: 60-60 rule, 60 60 rule, 60/60, sixty sixty, 60F 60% rule
- 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"

The 60/60 rule is a popular drying guideline: hold the [drying room](https://genetixbay.com/knowledge/glossary/drying-room.md) around 60 °F (about 15.5 °C) and 60% [RH](https://genetixbay.com/knowledge/glossary/relative-humidity.md). At those settings, buds lose water slowly and evenly, usually reaching jar-ready in roughly 10-14 days, depending on bud density and how much stem and leaf is left on.

## In practice

The rule works because it slows evaporation from the bud surface to match the rate water can move out from inside. That avoids [case hardening](https://genetixbay.com/knowledge/glossary/case-hardening.md), helps [chlorophyll](https://genetixbay.com/knowledge/glossary/chlorophyll.md) break down, and keeps more of the volatile [monoterpenes](https://genetixbay.com/knowledge/glossary/monoterpene.md) that are lost fastest in warm, fast dries.

It is a target, not a law. Many growers run 60-68 °F (15-20 °C) and 55-62% RH with good results. What matters is a slow, even dry with no mould. Adjust for your material:
- **Wet trimmed, small buds**: stay at the cooler, more humid end.
- **Whole-plant hang, dense colas**: watch mould risk; a little lower RH or more air movement may be needed.

Measure at bud level with a calibrated hygrometer. Room-corner readings can be several points off.

## Don't confuse with

- **Jar RH targets for curing**: a proxy for [water activity](https://genetixbay.com/knowledge/glossary/water-activity.md), a separate measure.
- **Water activity**: the bud's own measure of available water.
- **VPD**: a growing metric, not a drying rule.

## Related terms

[Drying room](https://genetixbay.com/knowledge/glossary/drying-room.md), [Hang dry](https://genetixbay.com/knowledge/glossary/hang-dry.md), [Water activity](https://genetixbay.com/knowledge/glossary/water-activity.md), [Terpene loss](https://genetixbay.com/knowledge/glossary/terpene-loss.md)

## Read more

- [Drying cannabis: the 60/60 method and water activity](https://genetixbay.com/knowledge/harvest-cure/drying.md)

## Sources

1. University of Georgia (thesis). Effects of drying method and storage on cannabinoids and terpenes in hemp. https://openscholar.uga.edu/record/27813
2. Ross SA, ElSohly MA. 1996. The volatile oil composition of fresh and air-dried buds of Cannabis sativa. Journal of Natural Products 59(1):49-51.