Drying and storing so the potency survives

Two drying regimes — choose by plant part

| Material | Method | Temperature | |---|---|---| | Aromatic leaf (mint, lemon balm, sage, thyme, oregano) | Shade, ambient, moving air | Under 35-40 C, ideally ambient | | Flower (chamomile, calendula, lavender, rose) | Shade, ambient, single layer | Under 35-40 C | | Root (echinacea, valerian, dandelion, ginger, turmeric) | Warm, ventilated | 45-55 C | | Bark | Warm, ventilated | 45-55 C | | Seed (milk thistle, fennel, dill) | Warm, dry, in a bag | Ambient to 40 C | | Berry (elderberry, hawthorn) | Warm or dehydrator | 45-55 C |

Shade and ambient drying — for aromatics

• A dark, dry, well-ventilated space with moving air
• Out of direct sun — sunlight degrades colour and volatiles
• Hang small bundles, or lay on a mesh screen in a single layer
• Turn gently every day or two
• Expect 5-14 days depending on humidity
• A small fan dramatically improves results in a humid climate

Warm drying — for roots, bark and seed

• A dehydrator set to 45-55 C, or a warm dry room
• Slice roots to 0.5-1 cm or split them; whole roots mould inside
• Spread in a single layer, not in a heap
• Until they snap, not bend, not merely feel dry outside

Freeze drying

• Best retention of volatile and labile compounds
• Needs equipment almost nobody has; air drying in shade is the practical alternative

The dryness test — do this

• Leaf crumbles; stems snap
• Root snaps crisply
• Seed rattles and is hard
• Jar a sample and check it the next day. Condensation inside means it was not dry enough — return it to drying.

Storage

| Enemy | Countermeasure | |---|---| | Light | Amber or opaque glass, or a dark cupboard | | Oxygen | Fill the jar high, minimise headspace | | Heat | Cool, stable temperature — not above a stove or in a sunlit window | | Moisture | Absolutely dry material, sealed jar, no fridge (condensation) |

• Label with plant, part, date and where it came from
• Keep whole; grind only as needed
• Check at one month and three months
• Smell it. A faint, dusty, hay-like smell means it is spent.

Working lives

• Volatile flowers and leaf: 6-12 months
• Other leaf: 12-18 months
• Root and bark: 2-3 years
• Powdered herb: about half of those
• Tinctures in alcohol: several years
• Infused oils: 6-12 months, refrigerated, and watch for rancidity

What not to do

• Do not dry aromatics in an oven, a hot car, or direct sun.
• Do not dry whole roots at ambient temperature.
• Do not store dried herb in a plastic bag on a shelf — the light and the plastic both cost you.
• Do not keep a jar past the point where it still smells like the plant.
• Do not grind a year's supply at once.