Skip to main content

Making use of microbes in the soil

Another paradigm shift….
I began the first summary page (Understanding Soil Minerals for Plant Nutrition) with a paradigm shift – adding several more mineral requirements to the traditional NPK in agricultural fertilisers. This post also requires a shift in thinking, this time we need to change the idea that all microbes, bugs and germs are bad guys. Actually there are an amazing range of bacteria, fungi, protozoa and even nematodes that can help us to grow healthy, resilient and nutritious plants, and release minerals from the soil so that we don’t have to pay for them. We need to support these helpers so that our job is easier, if we try to kill any that are perceived as bad, it can disrupt the balance and start to make life difficult for us.

eight acres: making use of microbes in the soil


The importance of humus
Organic matter in the soil is classified as either raw organic matter, active humus (consumed in about 6 months) and stable humus. The stable humus is most important for several reasons:
  • Retains moisture in the soil
  • Buffers pH
  • Retains and stabilises minerals (natural and added to the soil)
  • Detoxifies the soil by immobilising toxic heavy metals and sodium
  • Provides chelation complexes at the root zone
  • Promotes plant growth by storing beneficial plant chemicals
  • Humates, or humic acid, found in brown coal, can also be used to increase the humus content of soil.
The microbe connection
Microbes in the soil are the mechanism by which plants receive the minerals they need from the soil, as plants cannot produce enzymes, they rely on microbes, however plants also feed the microbes that help them. Failure to recognise the importance of microbes to plant health has resulted in increasing use of chemicals to treat plant nutritional problems (diseases), which results in plants that are both deficient in human nutrition needs and laced with toxic chemicals. The use of chemical fertilisers can prevent plants from supporting the microbes that would normally provide these minerals in the soil, and so they gradually die off. Salt fertilisers (most chemical fertilisers) test to create unpleasant conditions for microbe growth.

The role of microbes in the soil includes
  • Decomposition of organic matter in active and stable humus
  • Retention of nutrients, especially nitrogen
  • Releasing minerals from the soil
  • Producing CO2 close to the plant’s leaves for photosynthesis
  • Improving soil water retention by producing compounds that absorb water
  • Enhancing soil structure by producing compounds that aggregate soil particles
  • Producing plant growth hormones
  • Suppress diseases with a balanced population of different microbes with different prey
  • Encourage insect resistance through production of hormones

I also have a summary table explaining the different life in the soil, it didn't transfer to this post, so see the full document.

Increasing microbe populations
Microbe populations have been damaged by the use of chemical fertilisers, other chemicals (herbicides, pesticides etc), cultivation, growing monocultures and poor mineral balances.

Healthy microbe populations can be encouraged by:
  • Balancing minerals 
  • Improving soil structure and aeration 
  • Building organic carbon content of the soil – e.g. green manure crops 
  • Using specific soil foods such as kelp, molasses, humic and fulvic acids 
Microbes can also be introduced to the soil by seed inoculation and by spraying or direct injection of microbe brews (often called compost teas). Either a pure inoculum or a mixture of good microbes, such as compost, can be brewed in aerobic conditions to produce a concentrated mixture to be added to the soil, see the compost tea brewing manual. Different crops can benefit from different microbe balances, e.g. trees need more fungi, annual crops need more bacteria.  More on compost tea here and  here.

A simple test for microbe activity
Simply bury a strip of cotton fabric and inspect after a few weeks. The more decay, the more microbe activity in the soil.

How do you encourage microbes in your soil?

Comments

  1. Oh that is an interesting test - I will have to bury a piece of cotton....

    ReplyDelete
  2. I've heard all this and it makes sense. I know I try to chuck some woody mulch under the fruit trees if I can. I don't understand it all on a complex level though. It's very scientificky so I just go by 'if it's natural, it's good'. It seems to be working.

    I like the cotton test idea too. Might try it out.

    ReplyDelete
  3. I discovered just how poor our soil is the other day. I dug a hole to plant our first tree. Filled it with water and 30 minutes later the hole was still full of water!

    Am loving how informative your posts are Liz. thank you :-)

    ReplyDelete
  4. Hi all, glad I could help a little, this is a complicated subject and I'm sure it would take a lot of study to understand it in detail. Linda, all organic matter is good, and if you see lots of earthworms, you are definitely on the right track. The only people that really need to worry about the detail are large-scale/broad acre farmers that can't add organic matter in such large quantities and need to consider ways to improve soil biology to counter all the negative practices such as tillage. I will get into more of that soon.....

    ReplyDelete

Post a Comment

Thanks, I appreciate all your comments, suggestions and questions, but I don't always get time to reply right away. If you need me to reply personally to a question, please leave your email address in the comment or in your profile, or email me directly on eight.acres.liz at gmail.com

Popular posts from this blog

Worm farm maintenance

I have had the worm farm for over a year now, and I have to say it’s the easiest and most convenient way I have found to make compost and to dispose of vege scraps and other organic waste. I have not had much success with putting everything in a compost bin, I find that the food scraps go all sloppy and don’t really compost properly. I have found that my current system works much better, all food scraps go to the worms and the compost bin is for weeds and manure. The worms are able to eat all our food scraps and convert it to compost and worm tea, and there is still plenty for the compost bin, but now its not full of sloppy food scraps. People often ask if its necessary or possible to have both a worm farm and a compost bin, and I think it actually works better for us.



The worm farm really requires very little maintenance.  All I have to do is tip in more food scraps every few days, drain the tea once a week or so, check that the top tray is damp (if not, tip in half a bucket of …

Getting started with chickens - Tanya from Lovely Greens

Sign up for my weekly email updates here, you will find out more about soap and our farmlife, straight to your inbox, never miss a post!  New soap website and shop opening soon....

Farmer Liz: You will remember Tanya from Lovely Greens from the first series, she lives on the Isle of Mann and added chickens to her garden about a year ago.  You can leave comments for this post on Tanya's blog.



How many chickens (and other fowl) do you keep, what breed and what do you use them for (meat, eggs, slug control etc)?
Tanya: Around the same time that we were initially thinking about having hens another friend beat us to the punch. She went to the local pet store and bought a flat-pack hen house and chicken run combo and found a local farmer who had dozens of semi-feral chickens running around his property. One night he pulled three down from the trees and my friend took them home in a pet carrier. She named them Miracel, Carmen, and Geraldine and though they’re probably related they were all…

The new Eight Acres website is live!

Very soon this blogspot address will automatically redirect to the new Eight Acres site, but in the meantime, you can check it out here.  You will find all my soaps, ebooks and beeswax/honey products there, as well as the blog (needs a tidy up, but its all there!).  I will be gradually updating all my social media links and updating and sharing blog posts over the next few months.  I'm very excited to share this new website with you!