Solubility: The Basics
Something is soluble if it dissolves in a particular liquid: picture stirring sugar into hot tea (soluble) versus cold water (not). Many plant compounds that we use for medicine have to dissolve in the water/alcohol/honey/oil/etc. for medicine to be a thing.
Many plant constituents are polar, meaning they have a positive side and a negative side. The different sides are attracted to their opposites, so they can be pulled apart (dissolved) in a liquid that is also polar. The cliche chemistry rule is “opposites attract, like dissolves like.” Polarity is a continuum of different strengths: water is extremely polar; alcohol has both polar and nonpolar bonds (so call it “medium”), oil and wax are nonpolar. There is a lot more to this, but this is enough fluency for medicine-making. (Please don’t write me hate mail full of ionic and covalent bonds! If you do I will dip it in alcohol and it will dissolve!)
All plants contain both water-soluble and alcohol-soluble constituents. The question is how the medicinal compounds that you want extract best. The plants have a preference for the ideal balance to get the most well rounded medicine; make water-preferential or alcohol-preferential medicine based on what results you want (i.e. burdock tincture versus burdock vinegar).
Most plant medicine is best with a balance of both: dandelion, nettles, holy basil. Some really extract best in one or the other: slippery elm, marshmallow, echinacea. Remember that vinegar extracts water-soluble compounds (and in the case of minerals, is better than water at it) and oil extracts alcohol-soluble compounds.
To complicate matters: we still consume non-dissolved compounds in our medicine! Going back to the beginning, picture stirring sugar into hot tea. At a certain point, the tea is saturated and no more sugar will dissolve; any undissolved sugar will settle into the bottom of the cup. This undissolved sugar is still consumed, but it’s sediment at the bottom instead of being part of the liquid itself. This is what happens with sediment at the bottom of tinctures–usually fiber plant bones that won’t dissolve in the alcohol. Likewise, the volatile oils evaporating off the cup of mint tea still exist in the universe (and can be inhaled through your nose as you smell that lovely cup of tea), but they aren’t dissolved into the tea itself, which means they’re 1. very unstable and evaporating off quickly (not preserved) and 2. less available/absorbable into the body as medicine.
How to Tell
Intuition, observation, and practice!
Where it’s growing, how it’s growing, when it flourishes: intuition from experience. Does is grow on the banks of a river? On a wind-swept prairie? Does it bloom only when it’s very hot and sunny?
What worked last time? How does that season compare to this one? Is there a drought, or a late snow storm, or did the river jump its banks last fall and deposit fertile silt in your garden?
Taste, smell, & feel
Mucilage, berberine, tannin, resin: plants often directly tell you how to make medicine with them. Gooey demulcent mucilage is water-soluble, but sharp tingling berberine is alcohol-soluble.
Precipitate
The goop at the bottom of a tincture is the plant matter that didn’t dissolve in the tincture. Think about the goop at the bottom of a burdock or elecampane tincture–that’s the stuff that can’t dissolve in alcohol. Actually, it’s mostly fiber, which does for plants what bones and fat do for people (structure & food storage). Burdock and elecampane are both examples of herbs that tincture best at lower alcohol concentrations so their water-soluble compounds can play too. If there’s way more precipitate than there should be, it often means your tincture had too much or too little alcohol in it. That said, most high alcohol tinctures, especially of roots, will have precipitate, since plant matter always contains water-soluble constituents (see up, second paragraph).
Look it up in a good herbal reference
I recommend the works of Michael Moore and Lisa Ganora
Energetics of Solubility
These are generalizations meant to give you a place to start, not definitive truths for all plants. I’m developing a graphic for this but it’s not ready for the internet yet!
Plants that have very water-soluble medicine are often extremes on the wet-dry continuum:
Marshmallow Willow
Slippery elm Witch Hazel
Plants that do well with high alcohol tinctures are usually more in the middle of wet-dry, but on an extreme of hot or cold:
Echinacea California Poppy
Cayenne Skullcap
Remember, most plants make good medicine in both water- and alcohol-based preparations, but the individual effects still follow these basic guidelines.
For example:
Burdock tea: water-soluble medicine, benefits are dramatic on the wet-dry continuum with kidney & lymphatic actions
Burdock tincture: alcohol-soluble medicine, benefits are dramatic on the hot-cold continuum with liver & digestive actions
Old Ways Herbal: Juliette Abigail Carr 
Awesome and super helpful! Can’t wait to see the infographic!
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Do you have any information on the solubility of Jewelweed? I see a lot of people using oil to extract, however, I am curious if a water soluble solvent would extract more constituents?
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Yes, water is the best but you can’t really preserve it. I make jewelweed ice cubes for my husbands constant poison ivy. There’s an article about infused ice cubes in the medicine making section of the site, that method works well.
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Hello,
I was researching a problem I came across when making solar infused lemon balm in olive oil.
After straining off the plant material and later, decanting into smaller bottles I came across a gel like substance at the bottom of the bottle. Does this mean the oil is spoilt?
I read your article above but I understand that relates to a alcohol infusion?
Many thanks for your time.
Jane
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I tell oil is spoiled when it smells subtly like French fries. Olive oil goes rancid at a really low temp and doesn’t have a great shelf life, so it happens pretty regularly. I’m not sure about gel. It could be that you had some water on the plant matter that balled up in the oil, or it could be something not extractable (especially if it has some little sifty sandy bits). If you figure it out let us know!
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Great website BTW Juliette!
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Thanks!
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Great website!
Can you give any examples of compounds that are best extracted in carrier oils?
Oil is my prefered medium and I am having a hard time understanding what parts of the herbs are actually being transferred to the oil?
Any book suggestions you have that focuses on herbs in oil infusions or extractions would be very helpful.
Thanks
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Awesome and super helpful! Do you have any information on the solubility of Jewelweed?
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Water soluble. Very much so. Best preserved in ice cubes! There is an article about this if you go to the medicine making articles menu.
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Eurecka! I love that I found you and your impressive talents. I have tried to find you on FB and also shared my email on another site of yours…whatever way you came into my life or I came into my yours, it feels like Providence is answering a prayer. I am uber toxic with fluoride, mercury, aluminum, tin…suffering from decades of a mirade array of multiscourced toxin’s harm.
Using my own natural healing protocol, I have journeyed back from being in 24/7-full time-care-GONE to once again being able to advocate for myself and my healing. I do not yet know what you know which will help me in this next stage of recoverying my abilities, but I know you are right for me. For me it all about chelators and binders.
As soon as I read that herbs are either water or fat soluble, you had my attention,. These toxns are firmly ensconced in my toxin sodden fat cells. When this is liberated from cells, it becomes free circulating in my interstitial. Unless bound and eliminated safely, it can be reuptaken to new cells causing new harm. Thank you in advance for any guidsnce, help or knowledge I can acquire which will help in this quest to be as well as I can be.
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Hi Mo, I think I replied to you elsewhere, but this is too complicated for this format. If you’d like to schedule an appointment you can reach out through the appointments option on the top menu. Good luck!
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Awesome and super helpful! Can’t wait to see the infographic!
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Thank you I’m glad!
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Great website!
Can you give any examples of compounds that are best extracted in carrier oils?
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Anything that extracts well in oil—so the fat soluble compounds and most things that are useful topically
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Hey,
Love you website. I think you’re being trolled by bots. Amateur herbalist and aspiring herbal magician currently harvesting heaps of heather in Victoria. Take care!
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Thanks for your article. It was very interesting. My question is this: do beta acids dissolve into oils? I have hops. A treatment for mites in beehives involves the beta acids from hops. Can I extract the beta acids (lupulones) using traditional oil infusion methods? I don’t know if this is too technical, but you seem to have a better grasp on the topic than anyone else that I have read. Anytime I research hops all I see refers to beer making and the water soluable properties of hops. I have read about CO2 extraction, but I don’t know how to do this at home.
Thank you for your help!
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This is a great question. I don’t know the answer. My suspicion is that beta acids are likely not oil soluble because acids are polar and oil is nonpolar, but I could be wrong. Can you make a strong water infusion or tincture and use that instead? Please come back and tell us the answer if you figure it out!
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Thank you for your informed reply. I read somewhere that the beta acids were hydrophobic. So, I assumed oil would work. I guess its more complicated than that. How would I know that I had the beta acids anyway? There’s always more to learn!!
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I am part way through an advanced herbal medicine course and found your page. I just wanted to say I love it! Spread the knowledge🌿
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