What really does. 'Multipurpose Compost ' really mean to us?

Perhaps firstly. What do we mean by compost? then multi purpose??

Not necessarily going back to the dark ages. If inclined to sow seeds and pot-on etc. The garden or plot would provide the basic potting medium. Times passes so quickly and along comes a horticultural institute call, the John Inns Institute. (JI). This introduced us to gaining some insight asto what a potful of soil may require so as to cater for various plants. Older gardeners might recall setting about growing something special. Take x amount of garden soil. Now add two measures of this and that. It was like a cooking recipe.

Now we have garden centers where we can spend our hard earned dosh buying what is often nothing but someone else' waste. Much is going on respecting recycling. Bags of MPC vary so much, from composted plant waste to floor sweeping fom a London Main Line Train station.

So what really is the purpose of MPC.

 

This is a good question and I am looking forward to read opinions from more experienced gardeners than myself.

Compost makes for 60% of my total gardening expenses this year, even if I am using lots of things bought over the previous seasons, so that skews figures a bit.
I have been using quite a lot of soil from the back of the garden in the past, for beds and pots too. It is actually pretty fertile stuff, given I mulched with woodchips in the past and also grown mushrooms.

For me it comes down to:
1) No potential pests eggs/ larvae / harmful bacteria or viruses.
2) No weed seeds
3) The clover soil I normally buy does not compact as badly as my garden soil does
4) No need to remove stones and cobbles by the buckets
5) No potential chemical contamination. This is because the land of my garden, like many in London I think, was in the past used as dumping ground for construction waste and the back as a tipflying area for all kind of things. Because the garden is not flat, contaminants gets spread by rain. When digging some beds, the exististing soil smelled really bad, like a construction site.

Then, I have very little garden space and cram plants in, so I am a bit obsessed with avoiding potential problems. I use ring colture for pretty much all my large plants.
This said, I agree that it is quite a lot of money which would be nice saving.

Many of the above problems could be solved by high temperature composting. I am looking into it, but admittedly, even getting it right, I do not have enough waste to produce over 1000 litre of compost per season, which is what I would need to avoid buying any.