Good Soil Bugs – Make them feel at home, and make it good enough to eat!

Often referred to as the soil food web, a healthy, living soil will be teeming with microbes, both beneficial and pathogenic (infective; able to cause disease). Including species of bacteria, fungi, algae, nematodes, protozoa, arthropods and earthworms, soil microbes are all vital in maintaining a healthy soil structure.

Often we’ll hear of a garden that is receiving the best of everything but still not thriving, something is just not right. The problem could be lack of beneficial soil microbes. How can this happen?

There are a number of reasons for a lack of microbes including indiscriminate use of fungicides, biocides, herbicides, nematicides or fumigated landscape soils and high salt fertilisers.

Microbe brewing is one way to overcome these problems and is easier than beer brewing. In just 24 hours, in ideal conditions you can brew billions of microbes that will help bring your soils to life!

As with all garden inputs, wear gloves and a breathing mask to ensure you don’t breathe the microbes into your lungs.

Once you have brewed and applied your microbes help create a comfy microbe home with regular composting, add minerals like Soft Rock phosphate and feeding the soils with kelp, fish, aloe, molasses, humic acid and fulvic acid. 

Essential Oxygen (O)

Most beneficial microorganisms require good levels of oxygen to thrive. In fact, it could be argued that oxygen is the most important element in biological gardening. Aerobic soils are richly supplied with oxygen while anaerobic soils lack this element.  Earthworms create pathways for oxygen to enter the soil and calcium opens up (flocculates) the soil to let it breath. Gypsum can break up heavy clay soils to sponsor better oxygen intake, while compost can improve you soil to create a highly desirable crumb structure.  Light tillage with a fork can also help aerate soils.

Retaining moisture in your garden

Moisture retention is becoming more important as the cost of water increases and the availability decreases.  Climate change is likely to exacerbate these issues. Building humus in the soil becomes the most rewarding strategy to reduce moisture loss.

Humus improves soil structure and seriously increases your moisture holding capacity, If you can increase the humus levels by just 1% then every square metre of the soil can now retain 17 litres more water.

Composting is an excellent way to build humus, but you might also consider green manure crops whenever there is a chance. When green manure is dug back into the soil, the organisms convert the organic matter into humus. My strategy is to use Instant Humus, to encourage humus production.Yes, it is a product we sell, but it works so well! 

The most successful commercial composting system in the world is called CMC composting and it has some important lessons for the home gardener as well. It has been found that the addition of  10% clay has proven to produce a form of stable humus that can continue offering benefits for up to 35 years!

If you can’t access a friable clay, then you might add some soil or Soft Rock Phosphate.

Selecting compost and manures

Manures and composts come in may forms. In choosing to use any of them you should consider what you aim to achieve.

Mushroom compost has great levels of carbon and is terrific for building soil profile while not having an impact on nutrient levels.

Animal manures will have differing mineral analyses depending upon the source. Chicken (chook) manure contains good levels of phosphorous, while cow manure contains a greater overall mineralisation. All animal manures are a good source of the important minerals, nitrogen, potassium and phosphorous, and chook manure is also a good source of calcium.

All animal manures need to be used sensibly to avoid imbalance and nutrient run-off into the surrounding environment.  We need to strike a balance in garden inputs as an oversupply of nitrogen via manures can risk unhealthy nitrate contamination of our vegetables.

If manures are composted or purchased in a composted form then there is no risk of leaching or oversupplying nitrates because the nitrogen has been complexed and stabilised. Composting can increase the availability of the nutrients, introduce effective soil microbes and break down carbon into humus making it more effective in terms of water and mineral retention in the soil. Overuse of uncomposted material can lead to serious mineral imbalances and lock-up trace elements.

There is also the potential issue of weed seed contamination. Nitrogen in fresh manures is volatile and easily escapes into the atmosphere. Incorporating into a compost pile or digging the manure into the soil can help slow down this mineral loss.

Chook (chicken) manure is considered ‘hot’ when fresh. This means it is likely to burn delicate and sensitive plant roots and some soil microbes. It is a good strategy to compost this manure if that is possible. This manure has a fairly low carbon content unless it contains sawdust or straw.

Mushroom compost has a high carbon content but it is generally low in overall nutrient content. The pH of mushroom compost can range from 6.8 to 8. Preferably select a product with a pH below 7.

Cow manure and products made from cow manure have good levels of carbon and nitrogen but usually contains weed seeds as well.

Horse manure has great levels of carbon and breaks down quickly. Compost worms love horse manure but care needs to be taken to avoid manure straight after the animal has been wormed o vaccinated if it is to be used to feed worms. Once again there will the issue of weed seeds.

Green manure can be grown during the off-season or when resting beds in a rotation. Green manure crops build humus levels while feeding your beneficial soil microbes and earthworms. In warm areas try oats, Japanese millet, buckwheat, mung bean. In cooler areas, fava beans or fenugreek can be used.

Nitrogen – our number one soil nutrient

Nitrogen is the nutrient required in the largest amount for plant growth. In the natural scheme of things, nitrogen is largely sourced from the atmosphere where 74,000 tonnes of nitrogen gas hovers above every hectare.

Soil bacteria are responsible for the conversion of this gas into plant available nitrogen but they need good levels of calcium, sulphur and molybdenum to perform this role.

The aim of biological gardening is to optimise conditions for natural nitrogen fixation while supplying supplemental nitrogen in a natural form. Nitrate nitrogen is the form most commonly used in commercial home garden fertilisers and it is not conducive to the production of nutrient-picked, insect resistant crops. In fact, it encourages the exact opposite! Nitrates are taken into the plant with water and this dilutes all other nutrients. This mineral deficient plant then more easily falls prey to insect pests and disease. Just like a healthy human, a healthy plant has a strong immune system!

Nitrogen is the basis of vigorous growth as it is needed to build protein, hormones and enzymes. Along with magnesium it is the main mineral in chlorophyll, the green pigment that houses the sugar factories that produce glucose through photosynthesis. The best sources of natural nitrogen include compost, manures and fish fertilisers.

However, it is essential that your plant food contain molybdenum so that the plant has access to the “free gift” from the atmosphere – nitrogen.

Plant deficiency symptoms: a nitrogen deficient plant is often a thin straggly plant with fewer stems and poor vigour. The leaves are uniformly pale and yellow (including the leaf veins) 

Mulder's chart represents the relationships between minerals and why a correct balance is so important to achieve maximum mineral availability. 

Minerals and Micro-organisms

Minerals and micro-organisms are the basis of soil health, plant health and human health. Minerals and micro-organisms are the very essence of satisfying, problem-free productivity in the home garden.

Soil and plant health is not just about throwing nitrogen or phosphorous about the garden to fee our plants. It is more about balancing minerals. Good humus, healthy soil, is far more than applying lawn clipping compost to regenerate your microbe workforce. An imbalance of minerals and micro-organisms will result in poor production and unhealthy plants susceptible to pests and diseases.

Mineral imbalance is usually linked to calcium  and trace element deficiency, or to an excess of phosphorous and potassium, often due to over application of chook manure fertilisers. 

We use the Life-Force system from Nutri-Tech Solutions which contains cutting edge components that have previously only be available to large scale agriculture.

The Life-Force system was essentially developed for even the most inexperienced gardener.In my early days of gardening I was continually frustrated and disappointed by the sight of straggly substandard plants, that too often succumbed to pests and disease.  Many times I gave up as it was too hard, and a waste of my time ans effort. Now that I use Nutri-Tech products I harvest nutrient dense, medicinal foods for our family. We have a chemical free, organic garden and superb food that tastes delicious.

The home garden can be our own private wellness tool. The five step, Life-Force system has given me sensational results and the tastiest vegetables we have eaten in years.

the good earth

One of my secret loves, well, maybe it is not so secret as I discuss it with great enthusiasm, is compost. To be more exact, I adore making compost and using the compost that I make to grow my plants. Cheap thrills, and so satisfying!

My Dad used to declare that his compost was "good enough to eat" and I would laugh, thinking what a strange man he was. Now that I am older, and understand the process and the sense of achievement involved, I know exactly what he meant and how he felt as he worked with the fresh earthy soil. To think that nothing but kitchen and garden waste, paper, lawn clippings and cardboard can make rich dark soil that make plants grow brilliantly! Garden magic!

We have only ever had one of those dark plastic containers with a lid. At the moment we have three, so you can understand my enthusiasm for composting.

We anchor all the lids with a brick so that they don't go flying and become projectiles in storms or high winds. I like the little trap door at the bottom that allows me to access some of the older compost at the bottom. They are also easy to move around the yard if you are starting a new garden, or find carrying any weight of soil difficult.

However, they do have limitations. After a while they weather and the plastic cracks, and so after a time they require replacement. A little explanation as to how we ended up with three bin, also - never one to throw anything out when it still has a use, we use the old bins for things like lawn clippings and leaves and use the new, intact bins for mixes that include kitchen scraps.

This reasoning explains the second, draw back with the plastic bins. As they are open at the bottom rodents and toads can access them. Plastic bins also make a wetter mix than open bins made with wood, or chicken wire and so need more frequent aerating and balancing of dry or carbon based materials. We have also had rats gnaw through the plastic to access the yummy kitchen scraps (never put dairy or meat products in the bin as that is like an open invitation to vermin). I am sure that the same thing happens with open wood or wire bins also.  No one wants their neighbours to know that they have unintentionally opened a rat cafe in their back yard!

So, I am saving up for a deluxe metal compost bins. One of those rolls royce horizontal, tumbler models. I am not sure if it will be metal, or plastic as yet, though I am yielding to a metal one. I like the idea of it lasting a long time, and I love the idea of being able to give it a tumble whenever I add something to it. At the moment, I need The Agronomist to aerate and turn our compost, and I would rather have more independence in my composting! I believe the tumbling speeds up the composting process as well. More compost for the garden!

If anyone has an opinion for or against a particular compost bin please let me know. We have the average Australian backyard, so don't have room for one of those large custom made wooden structures with various sections such as one might find at the Botanical Gardens!

Back to my cheap thrills - I have potato peelings to take out to the compost bin!