Curing cannabis: definition, method and why it's essential

The curing (or treatment, is the stage of controlled cannabis conservation that follows drying and precedes consumption. It's a phase often overlooked by novice growers, yet decisive for the final quality of the product: aroma, smoke sweetness, potency and shelf life depend directly on it.

The principle is simple: after an initial quick drying, the flowers are placed in hermetically sealed containers under controlled conditions for several weeks. This process allows residual moisture to redistribute evenly, sugars and starches to decompose, and the terpenes to stabilize. The result: more aromatic cannabis, smoother to smoke and better preserved.

Why cure cannabis?

Without curing, cannabis dried too quickly retains chlorophyll, undegraded sugars and unevenly distributed moisture, resulting in acrid smoke, unpleasant plant aromas (smell of freshly cut grass) and faster degradation of the cannabinoids.

Curing performs several functions simultaneously:

Chlorophyll degradation The chlorophyll responsible for the vegetal taste and irritating smoke gradually decomposes during curing. Well-cured cannabis is smoother and more pleasant to smoke or vaporize.

Degradation of sugars and starches Residual sugars in the flower are metabolized by enzymes and aerobic bacteria during curing. Their undegraded presence results in a hotter, more pungent smoke.

Moisture redistribution Drying pushes moisture towards the heart of the flower. Curing in a jar ensures slow, uniform redistribution: flowers seem to «rehydrate» slightly at the start of the cure, before stabilizing at their ideal moisture level.

Terpene preservation Terpenes are volatile molecules that evaporate rapidly at high temperatures. Drying too quickly or too hot destroys much of the aromatic profile. Slow curing at low temperatures preserves the remaining terpenes and stabilizes their expression.

Long-term preservation Cannabis that has been properly cured can be kept for 1 to 2 years in an airtight jar without any significant loss of potency. Without curing, degradation begins much sooner.

The difference between drying and curing

Step-by-step curing protocol

1. Pre-drying

Before curing, the flowers must be sufficiently dry. The classic test: bend a small branch. If it breaks cleanly with a snap, it's ready. If it bends without breaking, it's still too wet. If it breaks into dust, it's too dry.

Target humidity before jarring : 60–65%. A miniature hygrometer placed in the jar is the essential tool for monitoring this precisely.

2. Bottling

Use only hermetically sealed glass jars (such as Mason jar, Le Parfait), glass is chemically inert and does not alter aromas. Plastic containers should be avoided: they allow chemical compounds to migrate to the trichomes.

Fill jars with two-thirds, no more. A jar that's too full doesn't allow sufficient air circulation when opened, and one that's too empty contains too much oxygen, which accelerates oxidation.

3. Burping (ventilation)

This is the key step in curing: open the jars daily for the first two weeks to renew oxygen and evacuate excess moisture.

Weeks 1-2 Open jars 1-2 times a day, for 5-15 minutes. If you smell ammonia or fresh grass when you open the jars, leave them to air for longer, as this is a sign that the humidity is still too high.

Weeks 3-4 Open every 2 to 3 days.

More than 4 weeks one opening a week is enough.

4. Storage conditions

• Temperature 18-21°C, avoid wide variations
• Relative humidity 58-65% in the jar, use Boveda 62 humidity packs to automatically maintain the ideal level.
• Light In total darkness, UV light degrades THCA into CBN and destroys terpenes.
• Location Store in: cupboard, cellar, drawer, away from heat and light.

5. Optimum duration

How do you know when curing is complete?

Three indicators:

The sense of smell aromas must be frank, complex and characteristic of the variety, with no hint of fresh grass or ammonia. Well-cured cannabis smells exactly what it promises.

The texture The flowers should feel slightly spongy under the fingers, without being damp. They should not crumble into dust, a sign of over-drying.

Hygrometry A hygrometer in the jar should indicate stabilization between 58 and 65%, with no variation from one opening to the next.

Curing and curing in jars vs. industrial curing

In large-scale legal markets, traditional curing in jars is being replaced by curing systems in controlled chambers, temperature, hygrometry and CO₂ automatically regulated over hundreds of kilos simultaneously. The principle remains the same, only the scale changes.

A number of alternative treatment techniques are emerging on the legal market, such as cold cure (low-temperature cure, 4-7°C) used for the piattella and some modern hashes, which preserves more of the volatile terpenes at the cost of longer duration.

Curing and storage

Well-cured cannabis keeps significantly better than rapidly dried cannabis. For a optimum preservation :

• Hermetically sealed glass jars with Boveda 62 packs
• Total darkness
• Stable temperature between 18 and 21°C
• Avoid refrigeration (condensation) and freezing (trichome degradation).