Questions & Answers

Compost tea is an aqueous solution full of biotic (beneficial microorganisms) and abiotic (including secondary metabolites, signal substances) components extracted and propagated from compost. The production of compost tea is done by aerobic (with oxygenation) processes.

EDAPRO Compost Tea is compost tea specifically adapted to areas of application.

Bacteria, protozoa, nematodes and fungi can be introduced into the soil through the compost tea. The organisms introduced by the compost tea are the basic length of the food chain and are thus indispensable for a fertile soil.

Compost tea is a sustainable alternative to conventional pesticides due to its disease suppressive (suppressive) effect through foliar and soil application.

No. Although nutrients are contained in EDAPRO Compost Tea, they are negligible in the nutrient balance. An essential component in EDAPRO Compost Tea are the beneficial microorganisms that stimulate metabolic processes and make nutrients contained in the soil available to plants (mineralize). Thus, EDAPRO Compost Tea can indirectly reduce the amount of fertilizer needed. If there is a nutrient deficit in the soil, fertilizer must be applied. Compost tea, on the other hand, does have a foliar fertilizing effect.

No. High disease pressure must be treated acutely and curatively. After the use of chemical pesticides, the application of EDAPRO compost tea is useful. EDAPRO Compost Tea has a preventive effect by strengthening the plants and their natural defenses. Thus, the cause of the disease is treated to prevent its symptoms.

The EdaBiom microbial substrate should be stored at a stable ambient temperature without fluctuations.

The optimal temperature range is between 15 – 20°C.

The EdaBiom microbial substrate must be protected from drying out (55 – 65% relative humidity). Rooms with high humidity, such as a storage cellar, are suitable for this purpose. If drying out nevertheless occurs, the EdaBiom microbial substrate should be moistened. If the EdaBiom microbial substrate is stored for longer than 3 months, it is recommended to loosen the substrate in the bags. This will prevent anaerobic zones.

Before storing the EdaLife brewing system, perform basic cleaning. The lid of the compost tea brewer should be closed after the cleaning is completed and prevents entries.

The term “Effective Microorganisms” (EM) was trademarked by Teruo Higa in 1970. EM is a mixture of about 80 different microorganism species, which are cultivated in the laboratory. EDAPRO Compost Tea contains about 500,000 different beneficial microorganism species from natural substrate. Due to the high diversity, the microorganisms in compost Tea can quickly adapt to locations or when the climate changes.

Additional liquid fertilizers can be added to the compost tea after brewing. Under certain circumstances, however, negative interactions between fertilizer salts and microorganisms may occur. A recommendation can therefore only be given with reservations.

Temperature plays an essential role in the production process of compost tea. The optimal range is between 17-22 °C. At cooler temperatures, the microorganisms multiply more slowly. At temperatures below 17°C, the manufacturing process should be adjusted to 36-48 hours. Temperatures of 30°C and above should be avoided if possible.

The microbial processes are responsible for soil fertility and growth, vitality and disease and pest resistance of the plant. The application of EDAPRO compost tea adds an enormous amount of microorganisms to the soil or leaf surface and brings many benefits:

  • Steigerung der Krankheits- und Schädlingsresistenz der Pflanze
  • Verbesserung der Nährstoffspeicherung und -umsetzung im Boden
  • Abbau von schädlichen Chemikalien, Pestiziden oder anderen Giftstoffen
  • Auflockerung von verdichteten Böden
  • Besseres Wasserrückhaltevermögen, geringere Auswaschung
  • Steigerung der Nährstoffgehalte in der Frucht oder im Gemüse
  • Reduzierung des Bedarfs an Pestiziden und Düngemitteln
  • Grossflächige Anwendbarkeit mit geringem Aufwand
  • Schnelle Zuführung von Organismen an die Rhizosphäre
  • Auch für die Blattanwendung geeignet

No. The brewing system should always be operated fully so that the aeration works well. If only half the amount of compost tea is needed, half the amount of microbial substrate and microbial food can be used. This compost tea should be considered a 1:1 dilution at the end of the brewing process.

Normally, the compost tea is brewed for 24-48 hours. If the compost tea cannot be applied during this time, do not switch off the air pump but extend the brewing time. If the brewing system has a heater, it should be switched off. The maximum brewing time should not exceed four days, otherwise the microbial diversity will decrease.

Yes, water of drinking water quality without chlorine, rainwater or osmosis water is suitable for the production of EDAPRO Compost Tea. For foliar application, make sure that it is soft water with a water hardness below 7 °fH.

Negative effects of overdosing have not been observed so far. Since the nutrients are bound in the bacteria, there is no danger of applying too much compost tea.

EDAPRO compost tea only contains the microorganisms that were present in the microbial substrate (EdaBiom) at the beginning. Due to this fact, the plant-strengthening effect of the EDAPRO compost tea can only be guaranteed with the microbial substrate EdaBiom from EDAPRO.

The beneficial microorganisms in the compost tea need
oxygen. During the production process, the organisms are strongly multiplied. As soon as aeration is stopped, the oxygen contained in the solution is quickly used up. If the oxygen content falls below a certain range (<5 mg/L), anaerobic organisms establish themselves, which can harm the plant. Due to the high oxygen demand, the compost tea must be used immediately after the brewing process and can be kept for up to a maximum of 4 hours.


Info-Broschüre (2 MB)

Info-Broschüre Hobby (2 MB)

Operating instructions EDAPRO Compost Tea brewer V60-V200

Quick start guide for EdaLife compost tea brewers V60-V200

Operating manual EDAPRO Hobby compost tea brewer (0.6 MB)

Instructions plant sap analysis (0.2 MB)



Compost tea for golf turf


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Winning the Agri&Co Challenge


Soil food web presentation

Scientific studies

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Diver, S., 2002. Notes on compost teas: a 2001 supplement to the ATTRA publication “Compost teas for plant disease control.” ATTRA publication, Fayetteville, Arkansas.

Fouda, S.E., Ali, A.S., 2016. The effects of the conjunctive use of compost tea and inorganic fertilization radish (Raphanus sativus) plant nutrient uptake and soil microorganisms. J. Soil Sci. 56, 81–106.

Ingham, E. R. (2005). The Compost Tea Brewing Manual, Oregon: Soil Foodweb Incorporated.

Iten, A. (2010). Wirkung von aeroben und anaeroben Kompostextrakten auf Pilzkrankheiten im Boden und auf Blättern. Bachelorarbeit, ETH Zürich, unveröffentlicht.

Ingram, D. T., & Millner, P. D. (2007). Factors affecting compost tea as a potential source of Escherichia coli and Salmonella on fresh produce. Journal of Food Protection, 70(4), S. 828–834.

Joshi, D., Hooda, K.S., Bhatt, J.C., Mina, B.L., Gupta, H.S., 2009. Suppressive effects of composts on soil-borne and foliar diseases of French bean in the field in the western Indian Himalayas. Crop Prot. 28, 608–615.

Martin, C.C.G.S., 2014. Potential of compost tea for suppressing plant diseases. CAB Rev. Perspect. Agric. Vet. Sci. Nutr. Nat. Resour. 9, 1–38.

Morales-Corts, M.R., Pérez-Sánchez, R., Gómez-Sánchez, M.Á., 2018. Efficiency of garden waste compost teas on tomato growth and its suppressiveness against soilborne pathogens. Sci. Agric. 75, 400–409.

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Rieger, L. (2014). Actively Aerated Compost Tea (AACT). Unveröffentlichte Semesterarbeit. Zürcher Hochschule für Angewandte Wissenschaften, Wädenswil.

Rieger, L. (2021). Einfluss verschiedener Komposte und Nährstoffzugaben zum Herstellungsprozess auf die bakterielle Zusammensetzung von Komposttee und dessen Wirkung auf die Pflanzenvitalität und des Auflaufens von Mais (Zea mays) und Gurke (Cucumis sativus). Unveröffentlichte Projektarbeit. Zürcher Hochschule für Angewandte Wissenschaften, Wädenswil.

Samet, M., Charfeddine, M., Kamoun, L., Nouri-Ellouze, O., Gargouri-Bouzid, R., 2018. Effect of compost tea containing phosphogypsum on potato plant growth and protection against Fusarium solani infection. Environ. Sci. Pollut. Res. 25, 18921–18937.

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Scheuerell, S. J., & Mahaffee, W. F. (2004). Compost Tea as a Container Medium Drench for Suppressing Seedling Damping-Off Caused by Pythium ultimum. Phytopathology, 94(11), S. 1156–1163.

Singh, B. K., Bardgett, R. D., Smith, P., & Reay, D. S. (2010). Microorganisms and climate change: terrestrial feedbacks and mitigation options. Nature Reviews Microbiology, 8(11), S. 779-790.

St. Martin, C.C.G., Dorinvil, W., Brathwaite, R.A.I., Ramsubhag, A., 2012. Effects and relationships of compost type, aeration and brewing time on compost tea properties, efficacy against Pythium ultimum , phytotoxicity and potential as a nutrient amendment for seedling production. Biol. Agric. Hortic. 28, 185–205.

Weltzien, H. C. (1991). Biocontrol of foliar fungal diseases with compost extracts. Microbial ecology of leaves, S. 430-450. Springer, New York (USA).

Al-Mughrabi, K. I. (2007). Suppression of Phytophthora infestans in Potatoes by Foliar Application of Food Nutrients and Compost Tea. Biocycle, 1(4), S. 785–792.

Ketterer, N. (1990). Untersuchungen zur Wirkung von Kompost-Extrakten auf den Blattbefall der Kartoffel und Tomate durch Phytophthora infestans sowie auf den Befall der Weinrebe durch Plasmopara viticola, Pseudopeziza tracheiphila und Uncinula necator. Dissertation, Universität Bonn, unveröffentlicht.

Kim, M. J., Shim, C. K., Kim, Y. K., Hong, S. J., Park, J. H., Han, E. J., … & Kim, S. C. (2015). Effect of Aerated Compost Tea on the Growth Promotion of Lettuce, Soybean, and Sweet Corn in Organic Cultivation. The plant pathology journal, 31(3), S. 259.

Marín, F., Diánez, F., Santos, M., Carretero, F., Gea, F. J., Castañeda, C., … Yau, J. A. (2014). Control of Phytophthora capsici and Phytophthora parasitica on pepper (Capsicum annuum L.) with compost teas from different sources, and their effects on plant growth promotion. Phytopathologia Mediterranea, 53(2), S. 216–228.

Marín, F., Santos, M., Diánez, F., Carretero, F., Gea, F. J., Yau, J. A., & Navarro, M. J. (2013). Characters of compost teas from different sources and their suppressive effect on fungal phytopathogens. World Journal of Microbiology and Biotechnology, 29(8), S. 1371-1382.

Naidu, Y., Meon, S., & Siddiqui, Y. (2013). Foliar application of microbial-enriched compost tea enhances growth, yield and quality of muskmelon (Cucumis melo L.) cultivated under fertigation system. Scientia Horticulturae, 159, S. 33–40.

Naidu, Y., Meon, S., Kadir, J., & Siddiqui, Y. (2010). Microbial starter for the enhancement of biological activity of compost tea. International Journal of Agriculture and Biology, 12(1), S. 51–56.

McQuilken, M. P., Whipps, J. M., & Lynch, J. . (1994). Effects of compost extracts of a composted manure- straw mixture on the plant pathogen Botrytis cinerea. World Journal of Microbiology and Biotechnology, (10), S. 20–26.

Palmer, A. K., Evans, K. J., & Metcalf, D. A. (2010). Characters of aerated compost tea from immature compost that limit colonization of bean leaflets by Botrytis cinerea. Journal of Applied Microbiology, 109(5), S. 1619–1631.

Pane, C., Celano, G., Villecco, D., & Zaccardelli, M. (2012). Control of Botrytis cinerea, Alternaria alternata and Pyrenochaeta lycopersici on tomato with whey compost-tea applications. Crop Protection, 38(8), S. 80–86.

Santos, M., Diánez, F., Del Valle, M. G., & Tello, J. C. (2008). Grape marc compost: Microbial studies and suppression of soil-borne mycosis in vegetable seedlings. World Journal of Microbiology and Biotechnology, 24(8), S. 1493–1505.

Spencerphillips, P. (2003). Phyllopshere Microbiology (107. Ausg.). The British Mycological Society.

Siddiqui, Y., Meon, S., Ismail, R., & Rahmani, M. (2009). Bio-potential of compost tea from agro-waste to suppress Choanephora cucurbitarum L. the causal pathogen of wet rot of okra. Biological Control, 49(1), S. 38–44.

Van Schoor, L., Denman, S., & Cook, N. C. (2009). Characterisation of apple replant disease under South African conditions and potential biological management strategies. Scientia Horticulturae, 119(2), S. 153-162.

Evans, K. J., Palmer, A. K., & Metcalf, D. A. (2013). Effect of aerated compost tea on grapevine powdery mildew, botrytis bunch rot and microbial abundance on leaves. European Journal of Plant Pathology, 135(4), S. 661–673.

Evans, K. J., & Percy, A. K. (2014). Integrating Compost Teas in the Management of Fruit and Foliar Diseases for Sustainable Crop Yield and Quality. Composting for a Sustainable Agriculture. Springer International Publishing, S. 661-673.

Larbi, M. (2006). Influence de la qualité des composts et de leurs extraits sur la protection des plantes contre les maladies fongiques. Dissertation, Université de Neuchâtel, unveröffentlicht.

Rieger, L., Rubi, A. (2016). Wirkung von aktiv belüftetem Komposttee (ACT) auf die Weinrebe. Unveröffentlichte Bachelorarbeit. Zürcher Hochschule für Angewandte Wissenschaften, Wädenswil.

Schmid, F., Moser, G., Müller, H., & Berg, G. (2011). Functional and structural microbial diversity in organic and conventional viticulture: organic farming benefits natural biocontrol agents. Applied and environmental microbiology, 77(6), S. 2188-2191.

Van Zwieten, M, Stovold, G., Zwieten, L. Van, Evans, K. J., Palmer, A. K., Metcalf, D. A., & Sc, A. K. P. B. (2013). Alternatives to Copper for Disease Control in the Australian Organic Industry. European Journal of Plant Pathology, 135(4), S. 661–673.

Van Zwieten, M., Stovold, G., & Van Zwieten, L. (2007). Alternatives to copper for disease control in the Australian organic industry. A report for the Rural Industries Research and Development Corporation, RIRDC Publication, (07/110).

Glöcklhofer, L., Lutz, M., & Rupf, R. Komposttee gegen Pilzpathogene auf intensiven Rasenflächen.

Rieger, L., (2021). Rhizobiom-Management auf Golf Greens. Wädenswil: ZHAW, unveröffentlicht.

Hsiang, T., & Tian, L. (2007). Compost tea for control of dollar spot. Department of
Environmental Biology, University of Guelph-GTI Annual Research Report.