Decoction, infusion, maceration: which preparation for which plant?

All medicinal plant preparation methods explained: temperatures, durations, plant parts, mistakes to avoid, and a practical summary table.

You bought beautiful plants from a herbalist, but how do you prepare them to get the best out of them? The choice of method is not anecdotal: it determines the extraction of active compounds and therefore the effectiveness of your tea.

Why method matters

A plant's active compounds don't all release under the same conditions. Essential oils evaporate with prolonged heat, mucilages are destroyed above 60 °C, tannins require boiling, and some compounds are only soluble in alcohol.

Infusion: for tender parts

Pour simmering water (90-95 °C, never boiling) over leaves, flowers or flowering tops, and let infuse 5 to 10 minutes covered to preserve volatile compounds. Suitable for: chamomile, mint, lemon balm, verbena, linden, lavender, rosemary (leafy parts).

Common mistake: directly boiling water with the plant. This destroys some essential oils and produces a bitter taste.

Decoction: for hard parts

Reserved for roots, barks, seeds and woods, which only release their actives at high temperature for a long time. Place the plant in cold water, bring to a boil, then maintain a gentle simmer for 10 to 20 minutes. Filter, and consume warm. Suitable for: valerian, ginger, licorice, fresh turmeric, dandelion root, willow bark.

Cold maceration: to preserve fragile compounds

Soak the plant in room-temperature water for 6 to 12 hours (often overnight). This gentle method preserves mucilages, vitamins and heat-sensitive compounds. Suitable for: marshmallow (root and leaves), flax seeds, plantain, mallow.

Inhalation and fumigation

For respiratory issues, pour boiling water over aromatic plants (thyme, eucalyptus, lavender) and inhale vapors under a towel for 5 to 10 minutes.

Summary table

• Thin leaves, flowers → infusion 5-10 min, water at 90-95 °C
• Thick leaves, flowering tops → infusion 10-15 min, water at 95 °C
• Roots, barks, hard seeds → decoction 10-20 min, gentle boil
• Mucilages (marshmallow, flax, plantain) → cold maceration 6-12 h
• Aromatic plants for breathing → inhalation 5-10 min

Frequently asked questions

Can multiple plants be infused together?

Yes, provided their infusion times are compatible. Avoid mixing tender leaves (5 minutes) with roots (15 minutes): prepare them separately then mix.

Should I sweeten my tea?

Honey is preferable to sugar, and some honeys (thyme, lavender) potentiate tea action. Add when water has cooled below 40 °C to preserve enzymes.