Turns out importing tons of soil for scientific experiments is really hard (or impossible)
Why we can not include soils from overseas in our greenhouse experiments in Germany
When we planned our new 2025/2026 greenhouse experiment, targeting as many as 600-700 pot experiments, we wanted to include a wide variety of soil types so we would create a very diverse data set. Apart from over 20 soils from Germany (photo shows the preparations at the greenhouse) we also wanted to include soils from other European countries as well as from overseas. Depleted, tropical soils are of special interest in the EW context because we expect the weathering to be faster/more effective in these soils.
Of course we did not want to create any bio-hazards or import some crazy bug or bacteria. We expected to be able to eventually get licenses/allowance for such imports if we properly treated the soil before transport or before use, through e.g. heat, gamma-ray-treatment or gas-treatment. That was our “just do it” naive practitioner's expectation. But…
Long story short: We failed.
The current EU and German regulations do not allow us to import foreign bulk soils and then use them in our greenhouse, except with special permission by the authorities which are given out only very restrictively. The fact that we needed almost half a ton (400 kg) per soil (several tons in total) made this especially complicated. Regardless of effort, money and willingness to kill the hell out of these soils before/upon arrival, we failed.
The long story
In April we wrote on our blog: “About 15 more soils from all over the world (from Europe, Australia, India, Africa, and the Americas) are expected to arrive over the summer and will also be used in the greenhouse (if everything works out fine with the logistics).”
Together with experts from companies specialized in environmental services, logistics and sea/air cargo we have been working on this logistics project for many months now. They were working on permits and import-regulations. In the meantime our partners in Australia, India, Africa, the Americas, Ireland, Denmark, Greece and Slovenia collected and prepared 400 kg per soil, and they were ready to ship on pallets.
But ultimately - even after spending more than 50k€ - we couldn’t get the necessary OK from German authorities. We had to cancel the logistics and we finally had to tell our partners to dump the prepared soil packages without sending them off. Needless to say that of course everybody involved was very disappointed.
We have heard from projects that were able to successfully import just small quantities for use in specialized labs only. But we can’t work with small quantities and we can not offer an hermetically sealed greenhouse either.
What alternatives do we have?
Unless you happen to know someone or some organisation that can make such imports possible (then we need to hear from you!) we will need to look into other alternatives.
Set up the experiments “on location”: We shortly considered setting up multiple greenhouse experiments abroad, but the differences in experiment setup, irrigation and temperature would make the data mostly incomparable to our data. And the cost/effort would be huge.
Mixing our “own tropical soils”: It should be possible to combine soils from Germany with sand or quartz to achieve similar characteristics of tropical soils - at least in part.
Use paleosoils from Germany: Paleosoils are ancient soil horizons that formed in the past under different climatic and environmental conditions (e.g. before the last ice age), later got buried and preserved within the geological record.
Use the “shaker experiment” approach on location to get at least some data from these soils: We found that a simple shaker experiment can give indications of CDR performance, this would at least be a small hint for our data.
Currently we are considering options 3 and 4. If you have tips for us in this regard, please let us know! Write to info@carbon-drawdown.de.
