Quick answer
Use one 8 gram two-way humidity pack for up to 1 ounce (28 grams) of weed in a sealed jar. For 1/2 ounce or less, use a 4 gram pack. For a full pound, use a 67 gram pack. Pick a 62% RH pack for most smoking and vaping flower. Pick 58% RH if you live in a humid climate or prefer drier flower that grinds clean.
Humidity pack size chart
- 4 g pack: up to 1/2 oz (14 g) of flower
- 8 g pack: up to 1 oz (28 g)
- 67 g pack: up to 1 lb (448 g)
- 320 g pack: up to 5 lb (2.27 kg) for bulk storage
These ratings assume a sealed container with little excess air. If your jar is much larger than the flower amount, use the next size up or move the flower to a smaller jar.
humidity packs for dry weed rehydration
Why pack size matters
A humidity pack holds a target RH by releasing or absorbing moisture. A pack that is too small for the flower weight and air space will dry out, then stop holding RH. An oversized pack works, but it takes more space and costs more. Match the pack to the weight of flower first, then adjust for jar volume.
cannabis storage humidity pack guide
Pick 62% or 58% RH
62% RH is the common target for cured flower. It keeps buds flexible and reduces the chance of overdrying. 58% RH suits users who want flower that breaks up with less stick, or who store in a humid room. Do not mix packs of different RH in one jar. The packs will fight each other and the jar will settle at an unpredictable level.
How to use a humidity pack
- Fill a clean, airtight jar with cured flower. Leave about 1 inch of headspace at the top.
- Match the pack size to the flower weight using the chart above.
- Place the pack on top of the flower or tape it to the inside of the lid. Keep it flat and away from direct contact with buds if you plan long storage.
- Seal the jar and store it in a dark place at 60 to 70°F (15 to 21°C).
- Check the pack every 2 to 4 weeks. Replace it when it feels stiff, crunchy, or dry.
Common mistakes
- Using a 4 g pack for a full ounce. The pack will dry out fast and stop working.
- Packing the jar full. Flower needs a little air space for the pack to work.
- Opening the jar every day. Each open cycle lets moist air escape and makes the pack work harder.
- Storing in a hot car or sunny windowsill. Heat pushes RH up and can cause mold.
When to replace the pack
Replace a two-way pack when it turns stiff or dry, or when the RH in the jar drops below your target for more than a day. In a sealed jar at normal room temperature, an 8 g pack often lasts 2 to 3 months. A 4 g pack in a small jar may last 1 to 2 months. Label the start date on the lid so you know when to swap it.