Can I use my own compost and food additives?
To obtain real benefits with compost tea, you need to apply tea that has high microbial diversity and numbers.
Compost quality is of the utmost importance. It must be free of pathogens and must be aerobic. Most farmers
do not give enough attention to their compost heaps. Typical problems are: the compost dries out; it becomes
waterlogged and anaerobic after excessive rain; the heaps are too wide and the centre is anaerobic; too little
nitrogen or moisture is applied and the heap does not heat up adequately, and inoculants are not used. Another
problem is that most farmers use their crop wastes. While this is a good practice for making compost, it is not
a good idea to use it in compost tea. The compost tea will contain the same organisms that are present in the
field or orchard and no real benefit will be achieved in disease suppression. If the plant material contains
disease causing organisms (pathogens) and the compost was not properly prepared, these organisms will be propagated
it the compost tea system. Compost tea must stay aerobic over the full brewing period. There must be at least 6
ppm dissolved oxygen as measured with a dissolved oxygen probe (DO meter). Adding too much food will stimulate
too rapid bacterial growth that will drive the dissolved oxygen levels below 6 ppm and cause the tea to become
anaerobic. Anaerobic bacteria produce by-products like alcohol that can harm or even kill your crop.
Disease-causing organisms grow better in anaerobic conditions. Our compost is of outstanding quality,
containing huge microbial diversity and the recipe is well researched by our microbiologist. There is no
need for you to measure your dissolved oxygen levels as our recipe will increase microbial numbers at such a
rate that it will not outstrip our compost tea systems aeration capacity.
Can I use my own tanks and only buy the other hardware?
It is essential that compost tea tanks should be properly cleaned. Ecosoil has open top tanks and are thus easily
accessible. They have a smooth inner surface which allows for easy cleaning. When water tanks are cut open, they
loose their rigidity. It is far more difficult to clean these tanks than ours.
What are Ecosoil’s tans capacity and can we use larger tanks?
Our compost tea systems are modular. Each tank has a capacity of 1200 L and the blower size determines how many
tanks can be run in sequence. Our recipes are based on these tank dimensions and cannot be used in larger tanks.
It is extremely difficult to clean larger tanks. The size of the blower is also determined by the water height. One
5 000 L tank will require a far more powerful blower than a system with four 1 200 L tanks. Other considerations are
adequate pick-up and agitation of organic material, preventing them from settling on the bottom and becoming anaerobic.
There are cheaper compost tea systems on the market. Why can’t I use these?
Numerous growers who used these systems have switched over to our system. Typical complaints are that they have
very limited capacity; they are difficult to clean; they produce poor results; that the compost quality is poor;
that their claims are not validated by results in the field and that growers receive poor after sales service.
When you use our system, you know you are using the best that is currently available in South Africa. Our team is
doing research and trials on a continuous basis and will keep you abreast of all new developments. Your business
will grow with ours.
If I have a power failure, what should I do?
Using a generator is the best practice. If you do not have a generator, connect your blower to the power supply
in such a manner that it will automatically switch on when the power comes back again. Our recipe is for a 48 hour
brewing period and consists of a day-1 and a day-2 food package. The oxygen demand is the highest between 8 and 24
hours after brewing starts. If you have a power failure during this period for up to two hours, it should not be a
problem. If the power takes longer to come back on, refrain from putting in the day-2 package and brew for an extra
day and then add the day-2 package at the beginning of the third day. You can test your tea by smell. If it smells
anaerobic, e.g. like rotten eggs, it should be discarded. You can also half fill a clean water bottle with compost tea.
If the bottle swells up or gas escapes when opened after 24 hours, it is not safe to use.
How long can I keep the tea without aeration?
4 hours when the brewing period is finished.
Can I brew for more than 2 days?
Yes, you will have more fungal growth the longer you brew. Keep in mind, though, that species diversity will
decline the longer you brew. Try not to brew for longer than 5 days.
Are there any farming practices that I must change when I use compost tea?
Fertiliser that MUST be avoided is potassium chloride (KCl). Rather use potassium sulphate or potassium nitrate.
Ammonium fertilisers are more harmful to micro-organisms than nitrate or organic fertilisers. Herbicides containing
paraquat are very harmful. Glyfosate are fine to use. Try to build organic matter and spray as little herbicide as
possible. During the second season of compost tea use, plants will show a higher resistance to disease. Try to
monitor pest and disease pressure before applying any pesticides. You may be surprised to find that you can apply
far less sprays.
Can I save on fertiliser?
A general rule is that you can apply between 10 and 20% less nitrogen during the first year of use, depending on
the amount of tea applied. In subsequent years you may save 30% on nitrogen applications. This figure will vary
between crops and production areas and each farmer will have to prove this to themselves. We have in the past save
as much as 70% on nitrogen over a 5-year-period. There are a couple of reasons for this: increased root growth which
allows for better uptake of applied nutrients; less leaching of fertilisers due to immobilising of minerals and a
carry-over effect to the next season; chelating of minerals and the mineralisation of tied-up nutrients.
Will I have less pest and disease?
Most pest and disease have a life cycle in the soil. By inoculating the soil with beneficial organisms pathogen
numbers will be controlled naturally. Far less disease is present on virgin land than conventionally managed land.
By using compost tea, you will create conditions similar to virgin land.
How much tea should I apply?
On perennial crops - 800 to 2 000 L per season, depending on the state of the plants and soil.
On irrigated annual crops - 800 to 1 000 L per season.
On dry-land crops – as much as is practically possible.
Can I apply too much compost tea?
Not that we have seen.
How do I apply the tea?
In irrigated crops – through the irrigation system. I diaphragm pump should be used. Centrifugal pumps damage
organisms. Best to work with pressures less than 6 bars.
On dry-land – it can be sprayed out on the soil and worked in with an implement immediately afterwards.
