FAQs

Compost Tea

1. WHY USE COMPOST TEA?

   The benefits of compost tea include protection of plant surfaces, retention of nutrients in the soil (no leaching, or erosion), greater nutrient availability to plants, improved soil conditions, increased rooting depths and better soil tilth. Compost tea is also safe to family and pets.

2. WHAT ABOUT ANAEROBIC TEAS?

   When a liquid becomes anaerobic, the beneficial fungi are killed because they are attacked by anaerobic bacteria, and protozoa and nematodes are killed from lack of oxygen. Thus, an anaerobic liquid does not contain the organisms that would normally be in compost. In addition, anaerobic liquids may contain highly toxic materials as a result of anaerobic metabolism.

3. WHY DON'T ALL ANAEROBIC TEAS KILL PLANTS?

   Because in many cases, with long enough brewing, the anaerobic organisms run out of food, and as the critters in the tea go to sleep, and stop using oxygen, then oxygen can diffuse back into the liquid. Then the aerobes can wake up and use the anaerobic metabolites. Thus, a strictly bacterial tea is produced, containing materials and organisms left from when the tea was anaerobic. Anaerobic materials can inhibit some disease organisms, but the brewing time is several weeks in duration, not overnight.

4. HOW IS COMPOST TEA USED?

   Apply to foliage and to soil. A pump spray device or sprinkler can be used. For foliage coat all plant surfaces as evenly and as completely as possible (if tea contains at least 2 micrograms of active bacteria and 2 micrograms of active fungi, typically 5 gal/ac are used). For soil, drench the soil completely (typically 15 to 20 gal/ac if the tea has adequate organisms; more if the tea does not contain adequate bacteria, fungi, protozoa and nematodes).

5. WHEN IS COMPOST TEA APPLIED?

   Compost tea is best when applied within a few hours after removing from the tea maker. Perform soil drenches during mild weather when the soil temperature is above 40 degrees. Apply first applications of foliar teas just before bud break on perennial plants, or at first true leaf stage on annual plants. Repetition is needed if bacterial and fungal populations are not maintained. Typical spraying schedules are every 7 days up to every 30 days, depending on weather conditions.

6. WHY ARE REPEATED APPLICATIONS NECESSARY?

   Toxic chemicals, dust and air pollution kill the organisms on leaf surfaces. Once the normal organisms are gone, then the exudates produced by the leaf material will be available for disease organisms if they land on the leaf surfaces. Repeated applications of compost tea mean healthier soil, healthier plants and less disease.

7. HOW LONG DOES IT TAKE TO MAKE COMPOST TEA?

   Brewing times vary with the brand of tea brewer, but are typically between 12 and 24 hours. Verify recommended brewing time in manufacturer's instructions.

8. HOW DO I KNOW I HAVE A GOOD TEA?

   Take a representative sample, and put it on a 100X to 400X magnification microscope, and look for the presence of beneficial fungi IN EVERY FIELD OF VIEW. Thousands of bacteria should be present per field, and several flagellates, possibly some amoebae and no more than one or two ciliates in 5 to 10 fields should be present as well. Beneficial nematodes should be present as well, 1 to 5 per drop of sample. Good compost tea IS DEEP BROWN IN COLOR, AND smells good with a pleasant earthy scent. Manufacturers should provide proven test results for your brewer. Your ingredients should be high quality.

9. WHAT IS THE DIFFERENCE BETWEEN COMPOST AND COMPOST TEA?

   Compost is a mix of organic materials which microorganisms have begun a significant process of break-downing. Leachable nutrients should NOT be present in high concentrations. Compost is a solid, while compost tea is a liquid. Decent compost tea typically contains a higher concentration of microbes and is easier to apply, because it is a liquid

10. WHY NOT JUST USE COMPOST?

    Compost tea can be applied to the leaves, twigs, bark and soil, whereas compost WILL NOT CLING TO LEAVES, AND THUS can only be applied to the soil. Both are very important to use, however, applying compost is more time consuming and labor intensive.

11. HOW OFTEN DO I APPLY COMPOST TEA?

    Compost tea should be applied at regular intervals. Benefits can be seen with as little as 2 to 3 applications annually. General maintenance practices are well suited for 6 to 8 applications per year. More frequent applications may be needed for stressed plant and soil conditions. more info

12. CAN I USE TOO MUCH?

    Compost tea is safe to use at the (recommended) application rates. Standard applications rates are used throughout the industry. Check your manufacturers' instructions. more info

13. HOW DO I KNOW THAT I NEED MORE APPLICATIONS?

    Observing the conditions of your garden will help you to determine if additional applications are needed. Frequent use is not harmful. Compost tea is a safe product.

14. HOW DO I SELECT A BREWER AND SUPPLIES?

    There are many reputable products on the market. It is important that your brewer and supplies manufacturer provide test results so that you know your equipment can produce a high quality tea. See our recommended list of products.

15. WHY ARE TESTS IMPORTANT?

    Testing is important because the biology in compost tea cannot be seen without a high-power microscope. The balance of biology is important to the health of your plants. Testing by your manufacturer tells you that the machine and supplies you purchase will make tea that contains a wide range of beneficial microbes with no pathogens.

16. CAN I BREW INDOORS?

    A good brewer can be used indoors or outdoors.

17. DOES THE QUALITY OF WATER I USE MAKE A DIFFERENCE?

    Yes. Clean non-chlorinated water is best. If you are on city water (chlorinated), you need to aerate the water until the chlorine is removed. This usually takes 60 minutes. Check your manufacturer's instructions. Chlorine will kill beneficial microbes. Water with chloramines as the material suppressing water microbes needs to be treated with humic acids to tie-up the chloramines. The concentration of chlroamine may very, so you need to work from a "worst case scenario." Always add at least 1 ml, or 1 teaspoon of humic acid per 100 gal, if you are concerned about chloramines, or other toxic materials in the water.

18. DOES THE TYPE OF COMPOST I USE MAKE A DIFFERENCE?

    Yes. Excellent quality compost is needed to produce a good quality compost tea. Each characteristic organism in the compost becomes multiplied in the tea during the brewer process. Thus the compost must contain beneficial bacteria, beneficial fungi, protozoa and nematodes, but should have been treated with good biology to remove, out-compete, consume, or inhibit disease organisms of all kinds.

19. CAN IT HURT MY CHILDREN OR PETS?

    Brewing tea with approved ingredients and equipment is not harmful to adults, children, pets or wildlife. Remember, this is not a chemical application. It is not, however, meant for human consumption. Compost tea contains nothing more harmful than good soil. If you routinely eat soil (not dirt!), then compost tea would not harm you. Given that vegetables and fruits SHOULD come with beneficial bacteria and fungi on their surfaces, the American Medical Association has said that each person should eat at least a pound of SOIL a year. It will keep the biology in your digestive system healthy. Just make sure the compost and compost tea have been tested for human pathogens. Look for the SFI Certified Product label.

20. WILL COMPOST TEA SOLVE ALL MY GARDENING / PLANT PROBLEMS?

    Compost tea may very well be the keystone practice to the success and health of your garden; however, it does not eliminate all other maintenance practices.

21. CAN COMPOST TEA BE USED WITH CHEMICAL FERTILIZERS?

    Yes. Compost tea will improve the health of the plants and soil even with the use of chemical fertilizers, however, it is recommended to make the switch to organic fertilizers. All inorganic fertilizers are salts. That means, the higher the amount you use, the more you kill the biology through a simple salt imbalance.

22. CAN I USE COMPOST TEA WHEN I AM USING PESTICIDES?

    Yes. Compost tea will assist the soil and plants to recover from the detrimental effects of pesticide or herbicide use. If you must use a chemical, follow it with an application of compost tea. All pesticides have non-target organism effects. Re-mediating the soil as soon as the pesticide has done its job of killing things.

23. WHAT OTHER PRACTICES SHOULD I DO WITH COMPOST TEA?

    Compost tea is not a "silver bullet" for the problems in your yard. Other practices, such as organic fertilizing, soil amending, mulching, aeration, etc., are also important to build and sustain a healthy garden. The soil, environmental and prior chemical condition of your yard all play a role in its overall health.