How to Cure Cannabis — The 4-Week Jar Process
You only need three cheap things
Curing is wide-mouth glass jars + a way to hold ~60% humidity + patience. A mini hygrometer per jar (or a 62% 2-way humidity pack) takes the guesswork out and is the difference between a smooth cure and a moldy one.
See Ball wide-mouth quart Mason jars on Amazon →Listen to the summary
The Short Version
A well-grown plant can lose 30–50% of its flavor, smell, and effect to bad drying and no cure. Curing — a controlled, slow conversion of chlorophyll, sugars, and terpenes inside airtight glass jars — takes 4 weeks and needs 1–2 hygrometer checks a day in the first week. We walk the whole protocol: drying RH/temp, the stem test, jar filling, burp frequency by week, and how to know a cure is done.
Watch this first
Official AC Infinity video — marketing, not an independent review
AC Infinity’s own video "Drying and Curing", on the same subject as this article. It is manufacturer marketing rather than an independent review: the drying and curing targets in the tables below are ours, not taken from this video.
Why curing really matters
Most mistakes in indoor growing are made after harvest. A well-grown plant can lose 30–50% of its flavor, smell, and effect to bad drying and no cure. A mediocre plant can genuinely improve with a good cure — up to a point.
Curing is the process where enzymes in the dried plant material slowly convert residues:
- Chlorophyll breaks down — that "green" hay aroma disappears
- Sugars convert into subtler aromas
- Terpenes reorganize — sharp top-front notes shift to deeper, rounder profiles
- Cannabinoids slowly isomerize — a tiny fraction of THC converting to CBN gives the typically "rounder" effect curve of well-cured material
All of it needs time, moisture control, and patience. Not heat, not sunlight, not open air.
Step 1: The dry phase (week 1)
Before curing can begin the material must first be properly dried. Targets:
| Parameter | Target | Why |
|---|---|---|
| Temperature | 64–68 °F (18–20 °C) | Too warm → terpene loss; too cold → mold risk |
| Relative humidity | 55–62% RH | Too dry → brittle, not cure-able; too humid → mold |
| Dark | Complete | UV breaks down cannabinoids |
| Light air circulation | Fan on the lowest setting | Stagnant air = mold risk |
| Duration | 7–14 days | Fast drying loses aroma. Slow drying keeps it. |
The stem test
Answer "is my material ready to cure?" with one test: take a thin side branch (3–4 mm thick) and bend it. If it snaps with an audible crack, it's ready. If it bends without breaking, dry another 1–2 days.
Crucial: the outside of buds feels far drier than the inside. A bud can be bone-dry on the outside while the stem still holds 65% moisture. Stem test, not bud test.
Step 2: Trimming + filling jars
After the stem test passes, trim the buds clean of fan leaves and larger sugar leaves (see how to trim). The resulting buds go into airtight glass jars — wide-mouth mason jars are the standard.
Fill jars to about 75%. Too full = not enough air exchange between buds. Too empty = you waste jars and the buffering is less predictable.
Measuring moisture in the jar
Curing lives or dies on moisture control. Two options:
- A hygrometer per jar: a few dollars for a mini-hygrometer (Caliber IV, ThermoPro, or similar). Put one in each jar. Target range during cure: 58–62% RH.
- Boveda 2-way humidity packs: a 62% pack holds the jar at 62% automatically by releasing or absorbing moisture. A cheap insurance net for beginners. Downside: they mask your own reading.
Boveda packs and Govee mini bluetooth hygrometers are both inexpensive on Amazon.
Step 3: The "burp" cycle (weeks 2–4)
Curing isn't static. You must open the jars regularly to exchange moisture, or they hit one of two problems:
- Too humid → mold. Moisture concentrates in the microclimate around the buds. Without air exchange it climbs to 65–70% and you have white mold spots 24 hours later.
- Too dry → brittle material. Without controlled rehydration the material drops below 55% and goes brittle — all the terpene magic stops.
Burp schedule
| Week | Burp frequency | Duration per burp | Target RH after closing |
|---|---|---|---|
| 1 (days 1–7) | 2× per day | 10–15 min lid open | 60–62% |
| 2 (days 8–14) | 1× per day | 5–10 min | 60–62% |
| 3 (days 15–21) | every 2–3 days | 2–3 min | 58–62% |
| 4+ (days 22+) | 1× per week | 1–2 min | 58–62% |
During each burp: smell the jar. Early week it smells hay-like (chlorophyll). By week 3–4 it transforms into the more complex profile. That's your signal the cure is working.
Step 4: When is a cure "done"?
Curing has no fixed endpoint — it slowly improves up to ~3 months, then stabilizes. Practically:
- 2 weeks cure: Usable but not at peak. Hay notes gone, terpenes starting to develop.
- 4 weeks cure: The sweet spot for most indica/hybrid varieties. Terpenes fully developed, smooth burn.
- 8 weeks cure: Premium feel. Especially sativa-leaning material improves further.
- 3 months+: Stable. Further change is marginal. Store in a cool dark cupboard (59–64 °F / 15–18 °C).
Common curing mistakes
- Jarring too soon. Stem test not passed → too much moisture in the jar → mold within 48 hours. When in doubt: dry an extra day.
- Plastic instead of glass. Plastic absorbs terpenes and off-gasses. Always glass (mason jars).
- Sun on the jars. UV breaks down cannabinoids in days. The curing cupboard must be dark.
- No hygrometer. Curing "by feel" works for experienced growers; for the first 5 cycles, always measure.
- Interrupting the cure. You can't "stop halfway" and continue later; once left open too long, the aroma is gone.
Bottom line
Curing is the step where most beginners drop off — it's boring work and the results only show up weeks later. But the difference between three weeks of curing and no curing is bigger than the difference between a $120 LED and a $400 LED. You've already done all the work to grow the plant — give yourself the 4 weeks to finish it.
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