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Compost Tea can be used in place of expensive, commercial liquid fertilisers in your Zone 1 kitchen garden. In applying these solutions you are delivering an explosion of benevolent microflora and microfauna to your soil… and your plants will love you for doing it. These teas can help suppress diseases and replace the agrochemical industry toxins that too many gardeners, in their ignorance, spray liberally all over the gardens, unaware of the damage they are causing. When we feed the plants liquid fertilisers (a free lunch) they respond by reducing the sugars that they deliver to the soil, which slowly starves the soil life and eventually over time makes turns sterile, this is what has happened and is still happening to the world's agricultural land. When we supply the plant with composting teas, however, we are working with nature, the plants are still provided with a flush of nutrients but we are also adding millions of microscopic workers around their roots, each one breaking down the mineral and turning them into soluble solutions that the plant can easily absorb. The more microbial life the more minerals available, this is feeding the plant in a natural way but actually we are not directly feeding the plant at all we are mere boosting the strength of the whole system… Though these teas also contain a range of essential mineral and elements that the plant needs, the key to the success of composting tea is the life-giving biota that they hold.

Composting teas don’t just get added to the soil they can also be harmlessly sprayed onto your plant's foliage to control foliar disease, which is a bacterial blight similar to brown spot and they can also deter pests. Compost Tea will invigorate your plant's growth, but also the beneficial organisms will deliver the food in the correct soluble form and in this way we are strengthening the symbiotic link between the plant and the planet. For many gardeners, compost tea can be even more valuable than compost, though the teas do not improve the structure of their soil, only feed it. Whether the gardeners realise it or not, composting teas are not truly fertilisers, it is actually, the quantity of microorganisms in the tea that are getting the gardener his amazing results.

We should not get confused between compost tea and the dark coloured leachates that might drain out of your compost barrel or worm farm. These leachates are likely to contain pathogens and if you collect them, I would not recommend you spray them over the foliage of your plants. Compost leachate usually needs further bioremediation, so I recommend you just tip them straight back into your compost bin unless you specifically need to reduce the moisture content in your compost. This leachate may contain some beneficial nutrients but they will have little in the form of benevolent microorganisms. Their value is more allotment legend than actual fact.

Making Compost Tea

Compost teas are brewed in a simple process using mature compost as its main constituent. The full ingredients are as follows:

 200 litre of water  10kg of mature compost.  2kg brown sugar (high carbon rich source)  20g fish meal (high nitrogen rich source)

You will also need an air pump, some flexible plastic tubing and some air stones. These can be obtained from any aquarium supplier.

There are two effective methods of getting a seed batch of composting microorganisms into the water.

1a. Using a sieve to break your compost down, you want it to be in small pieces, you are trying to avoid large lumps. Sprinkle this compost into a suitable container that is filled with the 200Ltr of water. Stir this mix occasionally over an hour and then let it stand for all the solids to settle on the bottom. You are looking for all the soil benevolent microorganisms to be released into the solution. There will also be an amount of nutrient and plant growth stimulant taken into the water. When the solids have settled you can decant the liquid and return the solids to your compost heap.

1b. Place you sieved compost into a burlap sack (or any porous bag, that can contain the compost) then put the filled sack into the water. Ensure the compost does not split out by tying string around the top. Do not allow the bag to sink to the bottom of the container. All the microbes will still go into solution, however, the whole process takes a little more time. It does, however, create a little less mess and is therefore less work to achieve the results you want.

2. Once you have your compost solution it is time to introduce the air and microbe food to the mix, this will result in the wanted expansion in microscopic life. Like all forms of life, the benevolent biota needs both oxygen and food to survive and thrive. The more oxygen we can get into the solution, the greater the population of microbes that it can support. You can aerate the water just by stirring the solution mechanically but this is not very efficient. The best method it to buy and air pump and using flexible plastic tube connect air stones. This is the type of setup you might see in a large fish tank to put oxygen in the water for the fish. This is very effective because each little bubble creates a large surface area for the gas exchange; so the more bubbles the better.

While the microbes need air they also need food and for them, this comes in the of carbohydrates. We can use brown sugar or alternatively black molasses as the primary food source. Along with the carbohydrates, we need to supply the microbes with nitrogen. We need to remember that their bodies C:N ratio is 5-8:1. Bacteria is actually one of agricultural richest sources of nitrogen (when the bacteria dies the nitrogen can be released to the soil). So like we do with compost we create the condition in which the microorganism can thrive and the food is included at an approximate 10:1 ratio, again balancing slightly on the carbon rather than the nitrogen side.

The moment the Carbon and nitrogen mix goes into the happily bubbling composting solution the population of microbe will start to grow exponentially. If you can keep the air flowing and while the food is still available the life will increase almost unbelievably. Bacteria numbers are counted in, colony forming units per gramme (cfu’s) if you get the condition right their numbers can grow over 11,000 times their original number, in just a few days. In studies, numbers can typically go from 32,000 cfu to 360 million cfu. So when you are putting this number of tiny generous, all giving, workers into the soil around your plants you can understand the positive effect they can make.

After three days, turn off the pump and remove the equipment. If you leave the tea aerating longer than three days, you must add more molasses or the good organisms will start going to sleep because they don't have enough food to stay active.

You now have a couple of options you can use all the brew to water your plants, or you can just take what you need, then top the container back up with fresh water, not forgetting to also add some more microbe food, plop the air stones back in and fire up the next batch of brew. If you do this it is worth, every now and again putting another bag of compost into the water, not for more microbes they will be very happy reproducing themselves, this is so that you can add some more trace elements back into the mix but this is not absolutely necessary.

Application of the compost tea

It is best to apply this magical solution directly to the soil and leaves of the plant using a watering can rather than a pressure sprayer. The bacteria have delicate bodies and when you have spent all that time trying to make them it seems a little silly killing them off in a pressure chamber. It is also best to not water during the brightest times of the day as the UV light will also kill the bacteria. So with this in mind, it is best to apply this precious potion in the early evening giving the organisms time to reach deeper into the soil. Those that are applied to the leave have the time to establish their own sunscreen.

Many people add more microbe food to the mix before the apply it to their gardens so that the microbes continue to multiply once in the soil, this is like sending them off to work with a well-packed lunch box and therefore they will not have to take any of the resources that are in the soil.

Four applications of this amazing liquid during the growing season is enough to see a huge improvement in the output of your crops. Some people, however, go crazy and apply every 2 weeks, this results in outstanding yields, with vegetable absolutely bursting with natural goodness.

When we look after the bacteria the soil will look after itself.

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