Mysteries of compost

[JDParticipant]

Interesting blog from Ridgedale Farm. Like yourselves, I have always believed the main benefit of compost to be the ‘life force’ it gives to the soil, rather than any NPK figures or the oft quoted humus water-holding ability. To this end, I have often wondered if there is any ‘good’ and ‘bad’ compost, or whether it all ends up the same, colonised by the bugs/fungi in the underlying soil to their blueprint.
You are usually told to mix greens and browns, chop up small so the bugs can work faster, and make sure there is enough oxygen for aerobic bacteria to predominate.
But what if you’ve put in too much grass and it’s all collapsed into a stinky, horrible, mess with anaerobic bugs dominating? Is this ‘bad’? Do you inoculate the soil with detrimental ‘bad guys’from which it takes a while to recover? Is ‘hot’compost better than ‘cold’?
Obviously each batch of compost made will come with its own microbial/fungal loading, is there any that plants prefer?
Sorry, rather profound stuff for this time of the morning. Don’t know if we have any experts left on the forum.
Just musing
Jan

[DerekParticipant]

Jan, you have entered a fascinating area. I also got interested in this and there is an awful lot more to compost than is generally talked about. From searching the web I have learnt that some plants, mainly trees and perennials, prefer fungal dominated compost whilst annuals prefer bacteriologically dominated compost. Another fascinating point I learnt is that plants exude substances from their roots to attract the right types of “microbe” to produce the plant food they require, right next to their roots. When you add artificial fertiliser the plant may stop attracting exuding this substance as it gets its nutrients delivered for free – briefly. Also, the fertiliser harms the microbes/fungus. I will never use fertiliser in the soil again!

[charlesModerator]

Two lovely comments, and happy to hear your new view on fertilisers Derek.
JD, Richard’s problem was that he spread raw material that looked like compost – it was still hot at spreading time. So its decomposition interferes with growth.
Yes anaerobic compost is of less benefit but at least when spread on the surface, it slowly aerates and becomes useful to soil.
It is indeed fascinating.

[JDParticipant]

Thanks so much guys. I thought I would get a duck with this one. Derek, that’s amazing and I would love to know more! I suppose the fungal preference for trees and perennials is because they’ve adapted to utilise their leaf mould/spent foliage from previous season(s) whereby the breakdown would be largely fungal by the time the plant came into growth again. Annuals probably opportunists after a ‘quick snack’ where they can get it, and maybe fungi are indications that there are tree canopies/competitors nearby?
I originally asked this after emptying one of my compost bins (trying to batch-compost to make as much as poss) and pondered the microbial mixture. I try to get it hot enough to kill seeds after my previous lot germinated over 1000 tomatoes, but not so hot that it kills off a lot of the good guys. Doesn’t always work, the batch I was emptying had got to 78 Celsius and I had struggled to cool it down!
Getting excited about next season to finally be able to put some ‘live’ compost on my beds instead of the largely depleted bagged stuff. Just got to try to remove most of the worms before spreading though or I’ll be plagued by moles again!
Thanks again
Jan

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