Coffee grains

[A&A]

I'm determined to produce a great deal of compost each year for the garden. Elsewhere on the web, I remember reading that plenty of people get wonderful results from used coffee grains. Even Starbucks promote its use - and give away bags of spent coffee free of charge to anyone who asks (apparently.)

Given that coffee grains are acidic (PH 4?) I can see how one must guard against being over-zealous with them. Does anyone here use them in decent quantities and how do you approach the PH issue? I've plenty of wood-ash so there's a possible solution there.

I went and spoke to the local coffee bar and I'm getting a bin bag per week of coffee. The neighbours are all collecting it for me (they think I'm mad!) and that's adding up somehow to another bin bag per week! I'm not talking about small bags either - I have no idea how they're drinking it all! Now I need to do something sensible with it and show them how its done. Anyone?

[becks77]

Coffee grounds are said to be a fantastic slug deterrant, but are no good in wormeries as the worms don't like coffee. but other than that probably just sling the grounds in the compost bin and mix really well
Becks

[homegrown]

Coffee grounds can also be used separately as the help balance out alkaline soil by increasing acidity, especially around tomato plants

[A&A]

Slug deterrent is a new one for me - if it has some effect then that's a bonus. Obviously, that'll mean scattering them on the surface of the soil. The wormery thing puzzled me since the wormery manufacturers all seem to tell you that you can use coffee grinds. My father-in-law feeds his regularly with them. Some of the advice online regarding coffee grinds seems to say that they actually encourage worms - some say in huge numbers. So perhaps the jury is still out on that one?

I did some soil (clay!) tests today all around the garden and I seem to have quite an acidic soil (PH 5.) Therefore, I've got to be careful with the coffee grinds - I tested them separately and got PH 4.5 for them. Perhaps some wood ash with them in the compost is the answer - I need to slowly increase the soil alkalinity for the benefit of most plants.

[becks77]

Mm having read the blurb in the link I'm now unsure wether the grounds in wormery is right or not it says not to in the stuff I read but this suggests its a good thing ..not sure. Sorry for any misinformation

[grahamhobbs]

We put coffee grounds into our wormery with no ill effect but not in the quantities you are talking about. However I wonder to what extent coffee grounds breakdown into compost, or rather how long it takes. I sense that in these quantities using them as a mulch, or possibly mixing with the top couple of inches of soil to avoid capping, might be the best way of using them, as they would provide a slug and weed resistant surface and a darkening of the surface aiding warming by the sun. Obviously you would have to keep an eye on the ph with liming as necessary.

[Green Aura]

I've been thinking about this for a while.

I was wondering if you could use them instead of peat to make acid compost, for things like blueberries which prefer an acid soil. And as a mulch round rhododendrons etc (not that I've got any of those up here ).

[Millymollymandy]

That's not a bad idea GA - perhaps mixing them with leaf mould which is a bit acidic I believe.

Mind you leaf mould wasn't acidic enough for my blueberry in my neutral soil (even though I planted it with tons of ericaceous compost in the hole) so it's now been planted in a tub with ericaceous compost.

[orangey]

I remember reading that coffee grounds aren't actually very acidic. Most of the acidity comes out in the coffee and you're left with something approaching neutral afterwards.

We drink a lot of coffee and I just sling all the grounds in the compost.

Edit: http://faq.gardenweb.com/faq/lists/soil ... 19975.html

Although it doesn't cite any references.

[A&A]

Most of what I've read online seems to suggest that coffee grains are generally quite acidic & Ph 4 is normally quoted. I tested the ones I've been given and got 4.5 so it does seem to back that up but perhaps different coffee & the efficiency of the coffee machines makes a difference? Who knows ;) The grains are currently going mainly into compost with a little wood ash to keep them closer to neutral

I've plenty of wood ash from the stufa and so since I have slightly acidic soil anyway, I've started adding it in small quantities to the beds. I'll keep an eye on the alkalinity and try and adjust the soil depending on what I plan to grow.

[Harasimow]

Haha every time i do somthing i find a thread on here about it! Just picked up a bag of coffee grounds from saisburys cafe yeasterday! Boo yeah.

[Mal]

I was wondering if you could use them instead of peat to make acid compost, for things like blueberries which prefer an acid soil.

Last year I started a bucket full of citrus peel with the plan of scattering them round my blueberries, possibly to include rhubarb leaves as well, and maybe coffee grinds after this conversation.

As it was, the bucket just sat outside the back door for a couple of months and then Mrs Mal made me throw it away because of hygeine concerns! Oops.

[Fred Hoggin]

Ants keep away from coffee grains.