making ericaceous compost?

[smoxi]

Wonder if anyone is doing this and if so what ingredients do you / would you include?

[tomc]

The idea of making a finished compost to be acidic. Presumably your going to add sulfur. Compost no matter how acidic the plant additions are, is going to end up just about neutral.

My two cents is its all going to be in the chemistry of fiddling with the finished product.

I'm even more of a sceptic if this 'compost' is to acidify alkaline soil. Or at least it never worked for me when I tried.

[applestar]

I'm thinking "compost" here is in the British and European English sense -- a blended planting medium -- rather than mixture of ingredients that are decomposed into humus.

What will this mixture be used for?

I do avoid peat moss now. I don't have anything that needs super acid growing medium but for more acid preferring plants, I generally add leaf mould of pine needles and sifted pine bark mulch fines. I also add UCG (used coffee grounds). My winter compost pile usually includes a large amount of orange peel and remains, so I tend to expect the resulting compost/humus to be on the more acid side and use it without any lime for them while adding some dolomitic lime for neutral to more alkaline mixture.

[smoxi]

I'm wanting to make a mix to plant blueberries in, I'm leaning toward keeping them in big containers or long term maybe making a raised bed for them. I have 2 plants, bought in the spring, they are very healthy and now about foot tall and are still in their 3 inch pots, very cramped, the planting medium looks to be just big chunks of bark.
As there are 2 plants I'm happy to experiment but am loath to buy compost re peat content and likely that it won't be organic or stock free (I work vegan organic).

I've got a separate bin to develop the mix in and did get a load of coffee grounds from a coffee shop as I'd heard that they were acidic and good for mulching ericaceous plants, its a very fine grind, almost powder but just read on another thread that the acid ends up in the coffee drink and so no longer in the grounds?

Other stuff I have I could put in the mix: huge amount of leylandii foliage both green and brown plus the small wood which I'm hoping would be on the acidic side,
I do have some oak bark but it is very dry and very brown.
I do drink copious amounts of tea, the tea I am sure holds its acid in the spent tea leaves as it always works to pink up the hydrangea or maybe its because the tea is still wet and the acid is working through that, interesting, maybe I should water the plants with cold tea!

No idea where I could get sulphur from, would it need to work in the mix for a set time before use?

[tomc]

If you have a lot of limestone in-under your soil you'll need sulfur. Sawdust amended with something nitrogenous will do for the organic part of your soil.

There just isn't anything compostable that remains as acidic as blueberry wants. Trust me I lived in lime-starved New Hampshire in the heart of blueberry country, and no home or commercial grower got their crop in with out sulfur. Even peat in unlimited amount is not equal to the lift you propose.

[ElizabethB]

Hydrangeas are pink in neutral to alkaline soil. They turn blue in acid soil. I highly recommend that you test the pH of your planting medium. You already know that blueberries like very acid soil. Our soil tends to be alkaline. Elemental sulfur is almost a necessity for blue berry production.

Good luck

[smoxi]

Very unusually for London I don't have any clay, the garden is on the remnants of what was an area of marsh overflow from the Thames so I've got fine sandy soil and as it was called a marsh and not a bog I guess its going to be pretty alkaline, I've never tested.

I have had a quick look about sulphur seems quite easy to get hold of and there's a nice piece on the RHS website:

https://www.rhs.org.uk/advice/profile?PID=82

I'm thinking to make a kind of acidic soil based mix for containers, it should be easier for testing and getting a thorough mix and in the mean time I may have to compromise with a bought bag of ericaceous for the short term, thank you I will begin to experiment and research more on blueberry requirements

Re the hydrangea, I should know this about the colours! It was my OH's long deceased mothers and it has become a kind of lore that she put the tea leafs to make it more pink, I've never even thought about it just continued the tradition!

[applestar]

I might be wrong but my impression is that used coffee grounds are not in of themselves acidic if you test their pH as already mentioned, however, they readily nourish/foster fungal growth, and THEY are what creates the more acidic environment.

[rot]

..
How do you keep Eric standing still long enough to make compost?
..

[toxcrusadr]

Haha, sounds like the type of corny joke I'd make.