Everyone knows how to make herbal tea. Regular tea is a kind of herbal tea – it’s made from the herb Camellia sinensis*. So anyone who has made gumboot will understand the basic principles of making a water based herbal medicine. You need hot water, dried herb, and something to brew in.
But beyond that, water based herbal medicines vary depending on what you are trying to achieve. There are teas, infusions, and decoctions for internal use. As I mentioned in another post, those terms get used interchangeably and contradictorily by different people, so here is what I personally mean in this blog when I use those words:
Tea: a small amount of herb steeped in hot water for a shortish amount of time. Can be a refreshment or a medicine, but is less strong than an infusion.
Infusion: a large amount of herb steeped in water for a long period of time. The greater amount of herb and the longer time both mean a stronger medicine and more parts of the plant are extracted.
Decoction: simmering herb in water, or simmering an infusion to reduce it down and increase the strength of the brew. Decoctions are by definition stronger than teas or infusions.
Some important principles:
One of the ways plants protect themselves is by having very thick cell walls. In order to get to the nourishing and medicinal bits of the plant inside the cells we have to break the cell wall. Three things will do that in water preparations: drying, heat and time.
Drying: for the most part dried herb will extract into water far better than fresh plant. You can try this for yourself. Find a non-aromatic herb that you have both dried and fresh eg nettle, raspberry leaf, or calendula. Make a tea from the dried and from the fresh by putting 1 tsp into 1 cup of hot water. Cover and leave for 15 minutes and then compare taste, smell and what they look like.
Having said that, some herbs extract well as fresh plants. These are herb that are high in volatile oils (the aromatic oils you can smell) eg mint, rosemary, thyme, lemon balm. You can make water medicines from these as fresh plants because the volatile oils may be the medicinal parts you want and they extract into the water very easily (and if it’s the volatile oils you are after, they often extract better from fresh plant than from dried). They also smell great.
Heat: heat will break down plant cell walls (this is true of food too, and is one reason why well cooked food is often easier to digest and more nutritious). Hot water, just boiled, is perfect for tea and infusion making, extracting most plant parts more effectively than cold water. Hot water and dried plants are a good match. Again, you can try this yourself. Take some dried herb and make a tea from hot water and one from cold water, and then compare after 15 minutes.
Decoctions also use hot water, but hotter than in tea or infusion. With a decoction, you simmer the herb, or heat it just below simmer, for a period of time. This additional exposure to heat will break down tougher cell walls and so is used for tougher plant parts like roots and barks. It can also be used for fresh plant, where there has been no drying to assist the cell wall breakdown. Rongoa (Maori herbal medicine) seems to be a tradition that uses decoctions more than infusions, presumably because of the easy availability of fresh plant.
And again there are exceptions to the rule. Some plants have mucilage in them, a substance that produces slimey or jelly like medicines that are good for soothing mucous membranes eg the digestive tract. Mallows and marshmallow are classic examples of this. Mucilage extracts very well into cold water.
Time: and thirdly, time allows for greater extraction of medicine from the plants. The longer you leave a tea or infusion to brew the stronger it will be. This is important if you are wanting to get nutrients like minerals from herbs, as it takes time for them to extract into the water. An over night infusion will have more minerals in it than a 20 minute infusion.
It is possible to brew some herbs for too long. Chamomile is best brewed (as a tea) for no more than 20 or 30 minutes, otherwise it gets quite bitter.
You can use any combination of those three things to make the medicine you want. For example, if you want a mucilage medicine you can use cold water, but still use time and drying to help access what is inside the cell walls. Sometimes you want to limit the extraction. Some herbs are just too strong to do as an infusion (licorice and thyme are two herbs I make as teas). Sometimes you want a medicine in a hurry, so a tea or fast decoction is better than an infusion.
Here are some standard recipes:
Lemon balm tea: take a handful of fresh lemon balm leaves, put in a tea pot, cover with 2 cups of boiling water. Steep 10-20 minutes.
Chamomile tea: put 1-3 tsp dried flowers in a tea pot and cover with a cup of just boiled water. Steep no more than 20 minutes.
Nettle infusion: take 30gm dried nettle leaf and put it in an agee jar. Add boiling water, being careful not to crack the jar. Stir with a wooden spoon to release air, and top up if needed. Put a lid on tightly, and leave to steep 4 hours or overnight. Strain and drink as is or reheat. This makes a nourishing infusion strong enough to supply large amounts of minerals that you simply won’t get from nettle tea.
Echinacea: put 30gms dried echinacea root in a pot and cover with 500mls water. Put a lid on and slowly heat until just simmering. Simmer 30 minutes. You can strain and use then, or leave in the pot for further infusing, taking out what you need over time. This method makes a brew strong enough to help heal bacterial infections.
These are guidelines, laying out time honoured ways of getting the best medicine from plants. If you learn and practice these rules, then you can learn where and when to break them.
*but it’s not really a herbal tea. Neither is green tea (it’s unprocessed regular tea) or regular tea with herbal additives (eg jasmine tea).