DIY potting compost

Unashamedly borrowed from a Gardener's World article :-

How to make your own peat-free compost
It’s also easy to make your own peat-free potting mix, using a mix of different ingredients, including well-rotted leaf mould, garden compost, vermiculite and garden soil. Monty Don recommends a mix of three parts coir, one part sieved garden compost, one part sieved loam and one part sharp sand, perlite or horticultural grit. Find out more about the some of the ingredients used to make peat-free composts, below:
Leaf mould – An excellent soil conditioner and easy to make yourself. If you have lots of leaves, try making a leaf mould bin to process large amounts, or on a smaller scale you can use plastic sacks.
Home-made garden compost –  Every garden should be able to produce this and the key is balancing green, leafy nitrogen-rich material with carbon-rich brown material, like woody stems and cardboard. 
Loam – Essentially garden soil, you can buy good quality loam (or topsoil) from the garden centre. Alternatively you can use old sections of turf, which you stack up, grass side down, and cover with tarpaulin. After around a year it will have broken down into good, loamy soil, which you can use in potting mixes.
Coir – A waste product from coconut plantations in tropical countries like India and Sri Lanka, you’ll often come across it in compressed blocks that expand when watered. It’s absorbent and an excellent open growing medium for sowing seeds and growing plants.

I might experiment with a home made John Innes type compost this year. B&M sell decent graded soil cheaply which I intend using with cheap peat free compost from Aldi and some course gritty sand  from B&Q (also reasonably cheap) Ratios of 7-3-1 seem to ring a bell, but I will probably just blag it until it looks about right!

I will add a wee bit of blood, fish & bone to the mix as well.

I'm thinking of doing something similar. I have a few coir blocks to rehydrate. and a small bag of perlite & vermiculite. I think B&M have gritty sand and I have some last year's Lidl compost, still in bags. Seems less risky than buying in some of the stuff that's on sale now.

My current recipe for potting mix for tomatoes and peppers is:

10% perlite
50% peat free compost
40% homemade compost/worm castings
6g of fish&blood&bone per litre

Used to use coir instead of peat free compost but the 5kg blocks are now almost double what we were paying a few years ago so it's cheaper to buy the compost.

Courgettes and potatoes don't care what they grow in so I don't use the good stuff on them. This year the potatoes are in:

10% coffee grounds
40% partially rotted horse manure
50% old potting mix or very unfinished home made compost
3g of 'spuds galore' per litre

I've got 3 x 50L bags of grass sod rotting down, hopefully we'll get some good stuff to use next year.

Definitely a good thread for me - I have the space to make enough compost myself, and enough horse manure to be self sufficient. Making my own potting compost will definitely help! Thank you for posting

Forgot to add, the reason for not putting more home made compost in my recipe is because it shrinks too much. You end up with a gap down the side between the potting mix and the pot wall, and when you water it all goes down that gap and straight out the bottom. To avoid the mixture becoming too compact and hard to keep wet you, need something in there that is more resistant to degradation. That's one reason why peat is such a good growing medium: it's very chemically stable. The coir, bark, wood fibre and woody bits in peat-free compost do a similar job.

My mix for both potting on and filling baskets is made up by mixing 12lts. of compost bought from asda, 4lts. of compost bought from home bargains, 6 lts. of soil/sand mix and 4lts. of perlite 80mg of chicken manure and 80mg of blood fish and bone, all well mixed then soaked and left overnight usually used the following day, I was hoping that I could avoid purchasing compost but there is no way I could make enough garden compost just now, I had added a lot of compostable waste into a bed where I am trying a form of hugelkulture plus the winter has been to cold and wet
Well for me to go out and turn it(rolleyes)

I'm bumping this thread as I've been looking at vermiculite prices with a view to mixing up my own compost this spring. I've never done it before but I was so disappointed in the commercial compost last year, I thought I'd give it a try. Any advice or comments welcome.

I’ve made my own potting compost for years.
16 liters of sieved well rotted compost
16 liters sieved mole hill soil
8 liters of washed river sand
6 good handfuls of general purpose biological fertilizer
Mix well and away you go!

Seed sowing
I part sieved well rotted leaf mould
I part washed river sand
1 part dry coffee grounds

I haven’t bought potting compost for years. The only compost I buy is to pot up things like Camelias and Blue Berries and that not very often.

I’ve made my own potting compost for years.
16 liters of sieved well rotted compost
16 liters sieved mole hill soil
8 liters of washed river sand
6 good handfuls of general purpose biological fertilizer
Mix well and away you go!

Seed sowing
I part sieved well rotted leaf mould
I part washed river sand
1 part dry coffee grounds

I haven’t bought potting compost for years. The only compost I buy is to pot up things like Camelias and Blue Berries and that not very often.

I think your seed sowing mix would probably be acid enough for ericaceous plants?