New Science on Dynamic Accumulators and Weed Tea

Gardeners speak lots about dynamic accumulators, and they’re vital for strategies comparable to permaculture and regenerative agriculture. The issue was that we didn’t have an accepted definition for them – no person agreed on what they had been.

The science of dynamic accumulators has just lately superior, and we now have a correct definition, an intensive database of potential candidates, in addition to some analysis supporting claims about them. There may be additionally new testing of weed teas comprised of them.

This will likely turn out to be extra vital to gardeners than you understand.

Key Takeaways

• We have now an official definition for Dynamic Accumulators.
• About 10% of vegetation within the database qualify as dynamic accumulators for at the very least one nutrient. None qualify for all vitamins.
• Vitamins in weed tea are decrease than most individuals count on.

A Definition for Dynamic Accumulators

In a earlier publish, referred to as Dynamic Accumulators – Do They Exist?, I mentioned the necessity for a definition for them and even proposed one among my very own:

A dynamic accumulator is a plant that can soak up and retain, within the leaf, at the very least one nutrient at ranges which are at the very least 10 instances greater than the common plant.

A key level of this definition is the “10 instances” part. We have now to ascertain a restrict.

Current work by the USDA and different scientists has developed a brand new definition which may be adopted:

A dynamic accumulator is a plant that can soak up and retain, in any a part of the plant, at the very least one nutrient at ranges which are 2 instances greater than the common plant.

Is the 2X worth cheap?

The 2X issue from the above definition, and my 10X issue, is unfair. Which one is extra cheap?

Let’s take a look at Russian comfrey for instance. It qualifies as an accumulator for potassium, producing 53,000 ppm potassium, primarily based on dry weight, and it produces 2.8 lbs/sq ft (recent weight). It comprises about 85% water, so a sq ft produces 190 g dry weight, which may include 10 g (2 tsp) potassium.

The common plant produces 4 g of potassium.

Is it value rising comfrey to get an additional 6 g/sqft of rising house? Remember the fact that you additionally want to reap and course of it to make use of the potassium. Alternatively, you possibly can develop a mean plant that you really want in that house and get 4 g.

Personally, I feel 2X is just too small to make dynamic accumulators a viable choice for getting vitamins, however my 10X might be too excessive.

The Dynamic Accumulator Database

A database of vegetation and their nutrient ranges was developed utilizing Dr. Duke’s phytochemical and ethnobotanical databases and made out there to the general public.

It comprises nutrient information (ppm primarily based on dry weight) for 350 vegetation, calculated from 7,000 information units. It reveals the outcomes for 20 totally different vitamins together with a Dynamic Accumulator Threshold (ppm) for every one.

The database is frequently up to date as new information turns into out there.

Abstract of Observations:

• Each nutrient has at the very least one dynamic accumulator.
• On common, 10% of the vegetation qualify as dynamic accumulators for every nutrient.
• There are extra accumulators for Ca, Cl, Fe, Mg, Mo, and S than for the opposite vitamins.
• Values for a given plant range lots primarily based on the nutrient stage used to develop that plant, leading to important variation for any given species.

That final level is essential to grasp. A plant is simply a dynamic accumulator whether it is grown in soil wealthy within the nutrient in query. Dynamic accumulators don’t exist in crappy soil.

Testing Dynamic Accumulators

As a part of the venture to create the database, a 2-year examine was additionally achieved to check 5 particular vegetation to get a greater understanding of the nutrient ranges within the plant and examine them to the database.

The next are a number of the key findings.

• Russian comfrey could possibly be reduce a number of instances a season and produced essentially the most plant progress (0.6-2.8 lbs/sq ft, recent weight).
• The vitamins which are accrued rely very a lot on the vitamins within the soil. “Whereas able to spectacular nutrient concentrations when grown in the proper situations, outcomes can range significantly from web site to web site. This implies that dynamic accumulators could also be higher fitted to tying up extreme vitamins in wealthy soil, slightly than extracting fascinating vitamins from poorer soil”.

Is Comfrey a Dynamic Accumulator?

Comfrey is the dynamic accumulator that’s talked about most frequently. I mentioned this query in one other publish earlier than this new science grew to become out there. The info out there on the time confirmed that it didn’t have any particular excessive ranges of vitamins.

The above-mentioned database contains Symphytum officinale, the frequent comfrey, which dynamically accumulates solely cobalt and iron.

Russian comfrey (Symphytum peregrinum) is the one most individuals develop if they need a dynamic accumulator. Surprisingly, there is no such thing as a entry for it within the database, displaying how occasionally scientists analyzed it. That being the case, why achieve this many gardeners imagine it’s a nice dynamic accumulator?

Weed Tea

Weed tea is a course of the place plant materials is added to water, allowed to ferment for a couple of days, after which the liquid tea is used as fertilizer. The method is totally described in my publish: Weed Tea, Fertilizer Tea – No Matter the Title, It Stinks

This check used rainwater with a pH of about 5.5 to make the tea. No agitation was used, and recorded temperatures ranged from 55.6°F to 84.9°F. The pH decreased throughout brewing as a result of virtually
quick onset of fermentation. Samples had been taken after 3 and 5 days of brewing.

• Usually, the nutrient stage was greater after 5 days than after 3 days, however this was not at all times the case.
• Cobalt, molybdenum, and nickel had been detected at zero ranges within the tea.
• Stinging nettle is an effective accumulator for calcium, and it transfers an affordable quantity to teas.

Many gardeners recommend diluting the tea as a result of “it is vitally concentrated”, however the above information reveals it’s already at an applicable stage to be used with out dilution.

The brewing course of doesn’t elevate the pH of the rainwater very a lot, which implies that the fertilizer answer can be pretty acidic and should have to be neutralized earlier than making use of to vegetation, particularly if brewed for greater than 3 days.

The third and fourth columns within the desk above present the share of vitamins extracted from the plant materials. It clearly reveals that a lot of the vitamins within the weeds are nonetheless within the strong materials and never within the tea.

A shock to me was that the % extracted for P and Okay are about the identical. Since phosphorus is sure up in giant molecules and potassium just isn’t, I’d count on a whole lot of the free potassium to finish up within the tea in comparison with the phosphorus quantity. Maybe it reveals that fermentation just isn’t disrupting a lot of the cells.

Do Dynamic Accumulators Scale back Vitamins in Soil?

You’d count on that nutrient ranges within the soil would drop if vegetation are pulling lots out of the soil, however that’s not what occurred. Soil assessments after the above plant experiments confirmed that the vitamins within the soil elevated, apart from sodium, which decreased.

This provides help for the argument in my publish on Is Soil Fertility Reducing? that implies that our agricultural soil just isn’t changing into nutrient-deficient.

The rationale for that is that vegetation excrete a whole lot of chemical compounds into the soil to help their rhizosphere microbe populations. All of this microbial exercise results in additional nutrient extraction from rock, making it plant out there.

The Minimize & Drop Methodology

The examine additionally checked out the reduce and drop technique, which they name the chop & drop. Within the reduce & drop composting technique, plant materials is harvested and easily unfold on the bottom the place pure decomposition takes place. The method provides vitamins extra slowly, however it’s straightforward to do.

This examine didn’t see a lot of an impact from this technique, however the materials was solely added within the last 12 months of testing, so it isn’t a shock that there was little change in soil nutrient ranges.

Ought to You Use Dynamic Accumulators?

The aim of utilizing dynamic accumulators is to supply an natural supply of vitamins. You develop the particular vegetation, harvest them, after which apply them to the soil, which is low within the corresponding vitamins.

You will need to perceive that no single plant is nice at accumulating all of the vitamins vegetation want. They aren’t normal fertilizer vegetation. You must choose those that present the vitamins you want in your soil, and use these.

However there’s a catch with that. In case your soil is lacking a nutrient, rising a dynamic accumulator in that soil gained’t retrieve a lot of that nutrient. They’re solely good accumulators if they’re rising in soil that has the nutrient you’re after.

This “catch” is even an even bigger downside when you think about that you don’t have any method of realizing the nutrient content material of the vegetation you’re rising, until you’re keen to do plant tissue testing. With out testing, you may undergo the entire means of rising dynamic accumulators and spreading them within the backyard with none actual profit.

Remember the fact that lots of the dynamic accumulators should not fascinating backyard vegetation, so you could dedicate a few of your backyard house to vegetation you wouldn’t usually develop. Is the time and house well worth the effort?

If the vegetation solely present a 2X improve within the wanted nutrient, then I don’t suppose they’re an excellent choice for many gardeners. They’re too sophisticated, take an excessive amount of house and time, and don’t produce sufficient advantages.