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steveberry

Q's re: dogs, coffee grounds and gardens

16 years ago

Hi,

I'm interested in using waste coffee grounds in my garden but I have a dog. I have a whole bunch of questions about the process-- mostly about dogs and coffee, and some just about the use of coffee in the garden.

First-- can I simply dig it into the soil without composting it, or is it too much of a "brown" to be used as anything other than a mulch? I know about the issues of digging in browns vs. using them as a mulch and have some concerns with coffee in this regard. Of course, part of the reason I'm considering digging it in is because I have a dog and don't want him to have ready access to it, incase he tries to eat it.

Second-- if I dig it in can it still be dangerous to dogs that might dig/eat some soil if its been mixed in like an amendment? My concern is that there's still going to be coffee grounds all around in the soil-- and dogs like to dig in freshly tilled soil. It sounds sort of like a recipe for problems, but I don't have any experience here. Am I being over cautious?

Third-- I've read that coffee grounds can mold when used as a mulch on potted plants (indoors and out). Is this true? And if so, why? Can it be prevented? I had a friend have a similar experience using soy bean hulls outdoors in a garden-- they molded and smelled bad on top of the soil, and seemed to sort of rot and decompose in a smelly way when mixed into the soil (in uncomposted form).

Basically-- how can I use coffee grounds in my garden (particularly if I have a dog)? I would love some input from those with more experience than I.

Thanks!

Comments (14)

  • 16 years ago

    40 +++++ years of breeding dogs qualifies me to assure you that you are way to careful.
    Pete

  • 16 years ago

    First, coffee is a green, not a brown.

    Most people sprinkle it on top of the soil and they don't dig it in.

    It could be bad for your dog, if he ate a lot of it. But frankly, he would have to eat a bunch. A little nibble here and there won't hurt him. One reason, I do fence off the garden and compost is to keep the dog out... I don't want him digging in the garden or snacking on the compost. The main reason I fence off the garden is to keep rabbits out...but it has a secondary advantage of keeping the dog out too.

    Primarily I use grounds in the compost and not directly on the soil, so I don't worry about the mold.

  • 16 years ago

    I put a lot of coffee grounds in my garden beds without composting them first. I had trouble with germination of peas and pumpkins. From what I read, the caffeine will inhibit the growth of roots of some plants. I recommend going easy with the amount of coffee you use in garden beds, especially in the spring.

    The corn seemed to be less affected by the coffee grounds.

    My dog has taken no interest in my compost bin, nor in the coffee grounds I put on the garden soil.

    I have tried drying out the coffee grounds and spreading them on the lawn. The lawn was not adversely affected by that.

  • 16 years ago

    Hmmmm.... ok.

    My intention is not to put them into veggie beds alone(which are located in a non-dog area), but to dig them into some new flower and planting beds that I'm creating to help the new plants get a big, powerful, Spring push.

    I am planning on mixing in some compost and using it as a mulch layer as well, so it could be done at the same time. Still, I guess it would be nice to hear some personal experiences with coffee and how beneficial (or not) it was.

    I mean, is it really worth mixing in the coffee?? Does it really have any substantial N benefit to the soil if I do so? I've been collecting some from coffee shops, but I'm not really interested in doing the work if it isn't really worth it.

    My understanding is that coffee is a pretty quick release organic fertilizer and that compost is pretty slow release and is really more about tilth. Thus, I thought adding them both would be really good for the plants. Does that make sense?

  • 16 years ago

    Steveberry said:

    "My understanding is that coffee is a pretty quick release organic fertilizer and that compost is pretty slow release and is really more about tilth. Thus, I thought adding them both would be really good for the plants. Does that make sense?"

    The simple short answer to your questions is to use a "mulch" to cover the coffee grounds. I always err on the side of composting everything that goes into my garden first, thus the plants have the best opportunity to get off to a great start. I would not say that compost is a slow release fertilizer due to the fact that compost provides more than just a small amount of N-P-K. The addition of both (coffee and compost) could be taken with the caution offered by other posters in this thread; it is very valid. However, there are other methods one can use to avoid any experienced shortcomings.

    Adding compost, using a mulch that is not "dog friendly" (possibly wood chips?), and adding other amendments to better get plants to grow in the manner one wants are but a few of the examples that can/could be employed. Your question makes sense, as well does all the suggestions (help) that have been offered thus far IMOÂ

    Blutranes

  • 16 years ago

    Thanks for this post. I recently started a weekly pickup of coffee grounds from my local coffee shop. I have been adding them to my worm compost bin and will add to the big heap outside once it thaws. The worms like the grit of the UCG and it provides nice aeration in the bin. Now if only those worms would eat faster, I could go through all of the grounds I have....

  • 16 years ago

    I'm not sure where that information about nutrients in coffee grounds came from but this is from Starbucks.

    Here is a link that might be useful: Nutrients and pH of coffee grounds

  • 16 years ago

    Did you read the link? The data was the result of a test conducted on UCG's from Starbucks conducted by a soil and plant testing lab that is international in scope. Soil, compost or amendment testing will always have some variability dependent on the sample and the quality of the testing facility and procedure. I don't see anything in the Starbuck's test that is significantly off from the other, although they don't specify a pH at all, only that the grounds are "acidic".

  • 16 years ago

    In the end, it seems like my idea of tilling it directly into the soil as a quick shot of N was a bogus idea..... oh well. :(

    Now I've just got all these bags of grounds in my garage!! Perhaps its time to start a compost pile. This has been, oddly, a hard thing to do, as I don't have a ready supply of greens to do a whole pile-- no lawn, and no lawns in my neighborhood. Hmmmmm....

    Thanks for all the info everyone.

  • 16 years ago

    Those coffee grounds are your greens.

  • 16 years ago

    Gardengal, I read it. I doubt most of what is there. Adding 1 teaspoon of lime per 5 pounds of coffee grounds is not enough lime to do much, and since the pH of coffee grounds falls in the 6.2 pH range, which is very close to what is optimal for growing most plants, there would really be no good reason to even think of doing that.
    That pH of 6.2 should also tell those that suggest adding coffee grounds to soils for plants that prefer an acidic soil that it is a waste of time and energy.

  • 16 years ago

    steveberry, you did notice people reminding you that grounds are a 'green', not a 'brown', right? Your other greens are all your kitchen scraps.

    You've got no excuse. :^]

  • 16 years ago

    Steveberry, you may want to read the FAQ, ( alink at the top of this forum) ... has a good description of greens and browns...

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