HOME > Chowhound > Gardening >


Pistachio Shells in the garden

We bought our house in November and I did my best to winterize the raised beds before the snow started falling. Now it's spring time and digging up the dirt out there, I've found pistachio shells, loads of them, in the raised beds, and they aren't crushed up or anything. I can't find any reason online for throwing pistachio shells into the garden, does anyone have any idea why they would have thrown their pistachio shells out there?

  1. Click to Upload a photo (10 MB limit)
  1. Misguidedness or laziness or slobbiness? I would guess that they'd take forever to decompose, even if they didn't have a lot of salt on them, which could be really bad news. But i'd ignore them, see how stuff grows and the shells may not be a problem at all. They might not hurt anything.

    2 Replies
    1. re: EWSflash

      Ha. That's what I figured, but I didn't want to say it in case there was a good reason for the shells being there. I plan to just shovel all the pistachio shells and egg shells into the compost pile, at worst they'll be a sort of marker on how the decomposition is going.

      1. re: zitronenmadchen

        Hmm, when I first read your post I thought maybe to keep the slugs away as the shells are sharp? I use crushed up egg shells to keep the slugs away since I don't have a compost heap....

    2. Once I went to the local pecan place. They were selling pecan shells as mulch. I got several bags and put it all out in my beds. The next morning the squirrels were going crazy out there.Too funny.

      I think it might be somebody's attempted at mulching.

      1. I've got pecan shells and pistachio shells in one of my perennial beds, and as DH ate a bowlful of peanuts last night, those shells will go in the garden, as well. We use wood chip mulch, so it just blends in fine.

        1. My guess is the previous owners watched lots of sports on TV and ate lots of pistacios in the process. Probably were using them as a way to aerate the soil and decompose at the same time. I wouldn't worry too much about them. They'll probably take forever to decompose but shouldn't do much harm. Just in case, I suggest getting your soil tested for salt levels. See if your state has a local university agriculture program - they usually offer soil testing services if you send them a sample of yoru soil.

          1. I've used seashells and eggshells in the garden, but never pistachio shells. My guess is a lazy attempt at mulching or composting. They wouldn't do a thing re. slugs...they'd just slime on over/around 'em. You can always "screen" the soil to remove them, if you desire. The shells can be a little acidic in large quantities as they leach, so if you plan to plant things that like "sweet" soil, I'd screen. If not, leave them be.

            1 Reply
            1. re: pinehurst

              What about if you crushed to pistachio shells ? Wouldn't that be bad for the slugs ?

            2. We tried (unsalted) peanut shells once, to no great effect. However, I also bought a bunch of bags of cocoa hulls. That was the same year I lugged home probably 50 pounds of Starbucks used coffee grounds (over several weeks), and the combined aroma of cocoa and coffee in the garden was wonderful! (I think it inspired some extra baking and extra pounds.) Our soil is highly alkaline, so we're always looking for less-chemical ways to acidify it.

              3 Replies
              1. re: pine time

                We do the Starbucks haul, too, pine time, for our evergreens. I feel shady posting this because no one in my area seems to know they offer the used grounds for free. It does smell great. I can imagine the cocoa hulls combo.

                1. re: pine time

                  Cocoa hulls, so you know, are very attractive to dogs, and very poisonous to them at the same time. I found that out from a Florida friend who posted that on a group email. I live in southern AZ, I don't think I've ever seen coco mulch for sale here, but it's good to know.

                  1. re: EWSflash

                    Very interesting, EWSflash. Luckily, we don't have a dog nor do any get into our back yard.

                2. Define "loads". I don't think they will hurt anything. I sure wouldn't sift them out unless you are talking about a very tiny space. They will rot eventually.

                  1. We eat a lot of pistachios and toss the shells into our compost. They break down eventually and don't seem to cause any problems.