Can I Mix Used Coffee Grounds in the Potting Soil?

15 years ago

Potting soil is my biggest expense by far for winter sowing... I read some of the posts about creating mulch and instant gardens with used coffee grounds as one ingredient, and I wonder if I can do something similar with the potting soil that I plant my seeds in. Can I extend my potting soil by mixing used coffee grounds in it? Would a potting soil/coffee grounds mix be a good medium to sprout seeds?

What do you all think? Good idea? Bad idea?

Thanks,

Lois in Pa

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Comments (4)

tiffy_z5_6_can
15 years ago
I would not use it. It is a food/green matter which is wonderful to use in compost, mulches and worked into the gardens (I do all three), but I would be wary of using it as a filler for potting soil since in that case it is not exposed to the gardening soil world of worms and the microherd. Once warm, in a potting soil environment, I can imagine it becoming moldy and possibly creating problems. I could be wrong because this is one place I've not gone with UCGs.

I have been gardening extensively with UCGs in the last 4 or so years. As an example, today I turned a pile of compost which I made last week which contained 200lbs. of UCGs, 6 bags of shredded leaves, and several pails of seaweed. I also created another pile nearly identical to last week's and inoculated it with some of the week old compost as it had reached a temperature of 155F. I bring home 200 to 250 pounds of UCGs every week and use it to amend the soil in the gardens and on our lawn in many ways.

I also cannot spend a fortune on potting soil every year but enjoy winter sowing so much that I need lots. Is there any place around you where you can buy your potting soil in bale form? I buy a bale of Promix every season for about $30.00. It is basically compressed potting soil and does the trick. I find mine at a store similar to Home Depot and can also get it at a garden center which is open year round for a bit higher price. If I know that things are tight financially, I will ask for it as a gift for Christmas or Valentine's Day (not kidding here) and will get it as such.

Hopefully others will give more insight. I wish you many successes in your gardens. :O)
jspeachyn5
15 years ago
Do a google for the compress bale.
I did and found a site that was offering free shipping about 2 months ago.
So it didn't cost me any thing extra and I didn't have to run around town and waste gas.
Just a thought.
As for the coffee in your soil.I agree 100% with tiffy.
Way back many moons ago. I tried to use it in the soil w/some house plants. BAD idea it molded and had to change out everything. So in the end it cost me more that a little to try to "help" my houseplants. :-)
This was a long time ago. Now that I have found the GW it is such a great wealth of info!
Bonnie
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terrene
15 years ago
I collect coffee grounds from the local convenience mart, but have never used them in pots. There was a thread awhile back in the Garden Experiments forum, about planting in coffee grounds. See link below for more info.

To stretch out your potting soil, perhaps you mix it with some other cheaper amendments, like a little sand (which is cheap at the hardware store) and/or home-made compost or leaf mold. I would add a little dolomite lime for ph and minerals. Maybe there are others too.

Here is a link that might be useful: Coffee grounds as a Planting medium
loisthegardener_nc7b
Original Author
15 years ago
OK, well it was a thought. I am glad I asked; I knew I would get some good information here!

Thanks for saving me from what would probably be a lot of frustration.

Lois in PA

Can I Mix Used Coffee Grounds in the Potting Soil?

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tiffy_z5_6_can

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Can I Mix Used Coffee Grounds in the Potting Soil?

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