Soil building with Dynamic Nutrient Accumulators – Comfrey

Today we talk about the importance of dynamic nutrient accumulators in your garden and we focus on my (any many people’s) opinion of the best plant for the job: Comfrey, Symphytum officinale. Not to be confused with wild comfrey, Cynoglossum virginianum.

As discussed in the video, here is a research paper comparing nutrient values of various liquid manures made from 3 different plants, comfrey being one of them, and then comparing them to animal manures.

Remember that the root zone/location of a plant performing this function is extremely important. Having a nutrient extraction zone farthest away from the root zone of other plants means that the nutrients taken to make the leaves of the accumulator is not from the same soil level that the other plants are taking theirs from. For this function we want DEEP TAPROOTED plants, and nothing can touch comfrey. Even if comfrey wasn’t such a heavy accumulator of nutrients, it would still be valuable simply for the depth of it’s roots. Combine that with a plant that dynamically accumulates critical nutrients like phosphorous, calcium, magnesium, zinc, etc, and you have a out-of-ballpark homerun addition to your garden and food forest.

For those “keyboard warriors” angrily typing how invasive this plant is, make sure you watch the last few minutes where I directly put these issues to rest. This is NOT wild comfrey, Cynoglossum virginianum. This is NOT other varieties of fertile-from-seed comfrey. This variety is STERILE, and will ONLY replicate via root cutting. So if you do not want them spreading, then simply do not sever the roots. It CANNOT spread without you consciously doing it. So put that anger away and join us in the peaceful garden, full of nutrient rich topsoil. (Can you tell I get that response a lot when I post about comfrey? lol)

One last thing…

There is debate on the edibility of comfrey. Some “studies” have shown it to be toxic, but the level of plant consumed in those studies was astronimical. If someone told you that eating a dumptruck full of iceberg lettuce made your tummy hurt, then isn’t the conclusion rather to not eat quite that much, instead of concluding that the plant was toxic?

Now I’m not going to get into this, and I never recommend anyone to eat anything, ever, for any reason. Yes, just starve instead of eating anything so that I am not liable for your health. Never eat. Anything. That way you cannot possibly get sick.

Still, if you do choose to make actual beverage tea with comfrey, or you choose to add some into your salad, just be aware that there are concerns with the toxicity of this plant, ONLY when used internally.

More info from, make sure to check out the link above:

Comfrey is a commonly used herbal medicine with a long and proven history in the treatment of various complaints. Comfrey is especially useful in the external treatment of cuts, bruises, sprains, sores, eczema, varicose veins, broken bones etc, internally it is used in the treatment of a wide range of pulmonary complaints, internal bleeding etc[4, 238, K]. The plant contains a substance called ‘allantoin’, a cell proliferant that speeds up the healing process… I hit character limit of description on YouTube… see more on their website…


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