Best supplier of compost 2025

In all my 60ish years of gardening I've not seen loam for sale for most of that time.
It was available here and there, but that was decades ago.
Loam is usually made by stacking grass turfs and allowing them to rot down, so it's not really a commercially viable product.
The closest you'll get to that would be something like a soil-based John Innes compost or a good quality topsoil.
Coir is very widely available now.
I've heard that Poundland sell it and I've seen it in most garden centres - eBay sell the coir bricks too.
The coir bricks are soaked in water then they expand.

PS - Happy Birthday

 

Thank you @Pete8 for the info and birthday wishes. I watched a video of Monty from 2018 where he showed how to use soil blockers and his mix included loam, I guess now (as it’s Monty) he would have made his own supply of loam. As the coir blocks are solid I think I might well find getting the mix right is going to be harder than I first thought!

 

It somewhat depends on what your going to put into it.
If you get a coir brick and soak it as per instructions you'll get a very fibrous and light medium.
Then it's a case of balancing that with your loam substitute - e.g. John Innes (soil-based) or topsoil.
If you're going to be sowing seeds, then you want a fairly light mix, say 75% coir, 25% loam substitute.
As the plants grow and need to be potted on, increase the amount of loam used to give more substance to the mix and support plant growth.

 

When we make a growing media using coir, then for seed & cuttings we would incorporated perlite, for a general potting we add 10% sterilised top soil. The added soil helps to prevent leaching of the nutrients.

When we make an orchid compost using coir, we use 45% of coir that has been passed through a 6mm screen with 5% sterilised soil and the other 50% is coir chips, which is coir but in sizes of 5 to 10mm chips for added drainage.

 

I think @CanadianLori uses blocks, not sure what medium she uses.

 

My mixes are: Seed Compost, equal parts of JI No1, Own Compost & Coir.
Potting Compost, equal parts of Own Compost, Coir, Perlite and feed.

 

Thanks for the detailed explanation @gks. It made me lose whatever hope I might have had that commercial peat-free compost will ever be really good at an affordable price. I guess I stick with what I'm doing to amend it.

Re. the sieving, I'm often amazed at the pieces of plastic, glass, wire and suchlike that turn up in bags of compost as well as thick twiggy stuff. Not saying I don't get any of that stuff in my own compost (usually it's plant labels and those little green clips, plus the occasional weeding knife) but I suppose I expect better when I'm paying for it.

It's interesting that the "green waste" is mostly brown. I suppose all the grass clippings etc that many people put in their green bins have already started to rot down and lost a lot of their nitrogen before it even gets to the composting site.

 

One of the mixes I’ve found online is
2 parts coir
2 parts perlite
3 parts compost
1 part garden soil
It’s definitely going to be trial and error (probably more error!). This one doesn’t say to change it so I assume it’s the same for seed sowing and potting on into the next size block.

 

Yes - I'd imagine that sort of mix would suit most stages of growth.
It's something we've all got to get used to now
Good luck

 

I have said this before but I think it's worth repeating. On Beechgrove garden programme the head gardener gave a quite comprehensive demo of the different mixes they used. It all started with peat free MPC, which he SEIVED, he then added various proportions of shaps sand, soil etc according to the use he wanted. It was shown over a year ago now, but should be on iplayer.

 

I have watched Montys video again and his mix is 4 parts coir, to 1 part of each of the following; leaf mould, compost, loam and perlite. I’ve emptied one of my compost bins and got 8 bags out, moved the leaf box, put back in the top 3/4’s and bagged up 5 of leaf mould, went to Wickes and picked up a split bag of topsoil (to use as loam) and OH has ordered some coir blocks to go with my soil blockers present. I have 1/3 bag of perlite left. So all ready for the big test and tryout next week, fingers crossed for some gardening weather.

 

Hope you got it for half price or less !! The hd poly bags they use are worth 50 p as well..,