Enhancing Photosynthesis with Compost Teas at Chaos Springs

Our Go Organic horticulture class had the privilege of a half day with Steve and Jenny Erickson at their 200 acre organic farm close to Waihi where they do dairy grazing, make certified organic compost that is shipped all over the country, sell lemons, garlic, potatoes and Steve's famous compost teas.  We were primarily here to understand more about compost tea production.

They purchased the 200 acre property in 2001and looking at the lush pastures today, it's hard to imagine it was once covered in gorse and ragwort. The ragwort problem inspired Steve to try compost teas.  Dr Elaine Ingham of the food soil web fame talks about weeds having a purpose as part of plant succession to build bacterial soil into a balanced bacterial and fungal soil flora. Pioneer plants in plant succession are often annual weeds with high nutrient value that grow quickly, die, and then lay down organic material to aid in building the soil biology. Pasture needs a bacterial fungal balance to be productive.  Weeds are the fixers or bandages on bare or depleted soils.

So if Steve was to just remove the ragwort it would not have served its purpose and next season would pop up again, just as it does for farmers who spray it.  He had to remove the ragwort because he needed to make an income grazing stock. In a home garden situation you could allow this cycle to play out before cultivating. So Steve collected the ragwort and made a plant extract and returned it to the land as a sprayed on tea.  Within one year he had got rid of the ragwort.

Steve showing up the mechanical
stirrer to replicate
the Bio Dynamic stirring process.

Steve makes aerated teas from diluted compost and plant extracts. He aerates mechanically to reproduce Steiners Biodynamic stirring process.

This machine creates a vortex one way and then the other.  The action changes the anaerobic solution into an aerobic one and the action of the churning the water separates the microbes from the plant material. This is important if you want to spray sieved material to ensure the microbes will be in the remaining liquid.

This vortex action is mesmerising.

Foliar feeding with compost teas create a liquid carbon pathway bypassing the solid state of carbon breakdown. This means the plant exudates grows the soil microorganisms faster.  The plant feeds the microbes sugars and in return the microbes through the plant's root system deliver all the minerals the plant requires to grow well. The pasture the animals graze or the vegetables and fruit produced have a sweet vitality.  Steve says the dairy farmer is over the moon about the condition of the cows when they leave his place at 18 months old.  They are fit for the task as milking cows.  Compost teas enhance the photosynthesis process - speed up the whole cycle.

Foliar feeding of plants with compost teas have created one inch of topsoil in a year in Australia.

Steve told us about the work of Australian, Dr Christine Jones and the Soil Carbon Coalition. Christine is a Soil Ecologist and has the nickname over there of "Carbon Goddess".

Steve doesn't use any other form of fertiliser apart from the compost teas on his land except for fine lime that he sprays on in a liquid form at the rate of 50 kg/hectare. Application with water also makes the lime available to plants faster than a powder form.

Steve has used Bio-dynamic preparations because he could see the results but being someone who needs to know how things work he was pleased to discover the work of  scientist Philip S Callahan who has been able to explain in scientific terms concepts such as paramagnetism affecting plant growth.

The other tool he has used has been plant diversification. He sites that the growing popularity of a herbal lay is good but 30 different plant species should just be the starting point.  He stated "a bag of seed is worth ten times more than a bag of fertiliser".   He suggested when we grow cover crops not to stick to one other species but add variety as plants do best living in a mixed community.

Trish taking a close look and sniff of comfrey plant extract that
Steve will usually add to each of his Compost Teas.

We then braved the rain and had the opportunity of seeing just how Steve makes his brews.

He uses plant extracts in two ways:

1. To deal to problematic weeds by putting the problem weed exudates back on the land.  He and others have had success with ragwort, Scotch and Canadian thistles, lawn daisies and one woman claims to have got rid of comfrey using this same method.
2. A general biological nutritional feed of soil biology and minerals for the soil.

To make his teas he may use a selection of extracts and add some sea water as there are so many valuable minerals in seawater. He makes plant extracts of hay, cut pasture, comfrey, and even gorse (chopped up) as it's an excellent source of nitrogen. Every plant has different mineral compositions and the pioneer weeds like nightshade are often especially high in nutrient value. He had us all thinking of the weeds we would dearly like to get rid of on our properties.  If nothing else making a tea of them will be satisfying because at least we can get the positive of that weed's nutrient value back on the soil. The effort of weeding them out is rewarded.

Steve showing us the tanks of different extracts.
He says the hay extract when he looks under the microscope
is "buzzing with protozoa..millions of them"

He has large plastic and stainless steel containers up to 2000 litre capacity. For a 2000 litre container of material and water he is likely to get 12-1300 litres of extract.

The 2000 litre stainless steel container has California thistles in it.  Usually he covers the containers but this one was left uncovered and the pasture seed in amongst the materials have started to grow on top of the liquid.

Steve pointing out the plant growth on top of the  California thistle extract tank.

He decided to leave the plant topping because  "those plants are photosynthesising stuff into the liquid". 

To make the extract:

Harvest weeds or plant materials including roots and attached soil, press down until it fills your container.
Fill with water.  They will become fairly smelly for a few days but the smell will go away.  Comfrey seems to always stink no matter what you do.
The plant material will float but will eventually over 3 to 8 weeks drop to the bottom and change in colour indicating it should be ready to be drained off as the nutrients have been extracted from the plant material.

To make a nourishing tea he mixes a number of extracts using about 10 litres of each including a dilution of his compost and seawater.  This is all diluted at least 20:1 with water.

To put on the land he has to first aerate with his mixing machine to change from anaerobic to aerobic.  This addition of oxygen kills any pure anaerobic microbes, and allows other microbes to convert from anaerobic to aerobic. Anaerobic pathogens that can cause harm are eliminated.

He has always made his extracts anaerobically and has found 30 minutes aeration is all that is needed to change it to an aerobic solution.  Spraying of course also aerates.

At home you can aerate by hand for half an hour stirring one way with your hand to make a vortex, then change to other way.  If doing this by hand I would add some warm water as part of the dilution to make it a more pleasant task as they do in Biodynamic stirrings.

Steve says you can just keep the extracts in the tanks until you need them.  He has some extracts that date back to one year.  Like with seaweed extracts the visual sign when its ready to use is when the materials sink to the bottom.

Steve did a number of tests to see if the visual signs of colour change and material sinking to the bottom stacked up with other scientific methods of monitoring.

He checked the temperature.  The temperature only raised a couple of degrees above ambient temperature and dropped down to ambient temperature in 4-5 days.

The other measure was pH.  The pH after 3 days had dropped down from neutral to 3 and over time it gradually returned to neutral.

He used an EC  (electrical connectivity) meter that measures the amount of minerals in the solution.  It doesn't tell you what minerals just how much. The EC metre measure started low and gradually rose until it started to level off.  The time it started to level off was the same time that the material dropped to the bottom.

Steve then showed us his mixer and spraying unit. His spraying unit
has no filters as there will be small bits of plant material in the tea.

On our way to visit his compost making set up he showed us his saltwater feeding station for the stock.  He says his cows fight over getting first licks of the fresh salt water he gets from the ocean 20 minutes drive away.

Seawater feeding station for stock

 Steve has been a commercial compost maker for many years both in the US and at Chaos Springs so he has an impressive array of machinery to enable him to make compost in large quantities.

Compost silver. The fine material is used in the compost tea.

Compost is made in long strips. He monitors for temperature, moisture and odour and writes down the results every day for the first month. For Biogro certification you have to have records of the heap reaching a temperature of 55 degrees C for 15 days and it has to be turned five times.

If the mix is perfect it will only need to be turned half a dozen times. You turn the compost to homogenise the materials and every heap can vary.

If it heats up too high over 65 degrees then he knows he has to add some more carbon. The test on whether the carbon nitrogen ratio is correct is if the temperature rises as expected.

 If it is taking too long to increase in temperature he knows that more nitrogenous material needs to be added and he will add some more grass or fish fertiliser to correct.

He prefers poplar, willow, aspen or avocado trees to pine as the carbon component because the tannins in pine make the compost process more difficult.  He told us that adding seawater can help raise the temperature of the heap.  He puts on 100 litres of seawater over each pile which is 30 cubic metres.

Manure is vital to the compost process and Steve has made a pen close to the compost area where he can put 100 cows overnight. The purpose is to gather their manure from one concentrated area.

Compost heap with fleece cover

The heaps are covered with a poly fleece that is light, black to attract heat and is permeable enough to let in some moisture but to keep excess moisture out.  Steve imported this fleece from the US.

So much easier to handle and looks so tidy compared with the recycled carpet we as home gardeners have to use.

The compost was impressive as was Jenny and Steve's home garden.
Jenny dug into her garden and the soil was picture perfect full of worms, dark, fine aggregates all holding together well.

Everything including Jenny and Steve looked full of life. The landscape with native bush backdrop was lovely including the hedgerows dividing up the paddocks.




Steve curses the Barberry Barberis vulgaris hedges as they are such prickly customers to maintain but I immediately spied the fruit ready for the picking.  He said we could help ourselves so I enlisted the help of Sinead with the promise of a jar of Barberry jelly for her efforts.