Coffee grounds vs. pill bugs

In our search for information on how to protect our new seedlings from pests my wife came across something, somewhere on the web about using coffee grounds to deter insects from attacking plants. We have been using this method for about three weeks now. Our findings:

Pill bugs are no longer interested in our plants - prior to our application of coffee grounds any new transplant was mauled and gnawed to the ground within 24 hours of planting. After applying the coffee grounds the pill bugs don't avoid the coffee grounds they just seem to ignore the plants. My theory is that the coffee grounds are giving off an odor/chemical that is masking the odor of the new plants. None of our new plants are being attacked by anything at all - I admit this is potentially circumstantial evidence at this point. But we have been seeing an increase in cabbage loopers and cut-worms on the established plants. So take this information with a grain of salt.

We have a patch of Vidalia onions about 6' by 2.5' and in the past week the pill bugs have taken to attacking them - they are very near our new transplants. We suspect that the pill bugs moved to the onions because the other plants were not as appealing. After an application of coffee grounds around each plant they are now bug free.

Application: We surround each plant with enough coffee grounds to cover the dirt completely - about 1/4" thick and about 2-3" wide.

Anyone else have a similar experience?

Hi Jerry,

Well...here I go again...another factoid of a multi decade debate with layfolk about "pill bugs" and "sow bugs," which are not a bug or any other type of insect as they have gills, and are actually a land crustacean. I am still waiting (35 years now...maybe this will be the one) where someone finds a garden variety of this animal that is actively eating a living plant...I am still waiting.

These little guys are "garbage people" and eat decaying veg matter...(with very small mouth parts) and do not eat (or not very well or effectively at all) living plants. Yes...yes...I know..."it has to be them, I see nothing else," or my other favorite..."they are all over the place...I know its them..."

I have seen even neotropical giant varities (and breed them in captivity)...guess what...they die if not given rotting veg matter...

So, if you have a picture of a sow bug or pill bug activly eating a plant...let me please see it. I am one of those "naturalist geeks" that has actually sat (for up to five hours) with a "convinced" gardener that it is the sow bugs eating there plants...guess what...it has always turned out to be a slug, snail, catipiller, hopper, or some other nocternal villian and the little pill bug is just there eating there other favorite food....poop!

Regards,

j

Nice littel link about "pill and sow bugs."

I too have heard that they "prefer" decaying matter over living. However, while I do not have any pictures as of yet I will get some for you when I see it happening. What I can say is that mine is not suspicion. I have personally, firsthand, witnessed them eating my new transplants and have also personally removed and squished them while they were doing so. In fact even this morning I observed a few of them on the onions where we had neglected to lay down coffee grounds. I disturbed the plants and flicked them off and then I realized I should take a picture but by that point they had all taken flight and were no longer in sight. I have found them on my peas, runner beans and cucumbers. In the case of the transplants they simply ate it. In the case of the larger plants they chew on the base.

I do have a theory about why a "garbage" eater is going after my "living" plants and that is moisture. I live in So Cal and it has been excessively hot and dry on and off the past few months. I think they are going after the plants for water. I neglected to mention this in my original post. I agree that they have a "preference" but in times of need any organism will eat something other than what it prefers to survive.

Jay C. White Cloud wrote:Hi Jerry,

Well...here I go again...another factoid of a multi decade debate with layfolk about "pill bugs" and "sow bugs," which are not a bug or any other type of insect as they have gills, and are actually a land crustacean. I am still waiting (35 years now...maybe this will be the one) where someone finds a garden variety of this animal that is actively eating a living plant...I am still waiting.

These little guys are "garbage people" and eat decaying veg matter...(with very small mouth parts) and do not eat (or not very well or effectively at all) living plants. Yes...yes...I know..."it has to be them, I see nothing else," or my other favorite..."they are all over the place...I know its them..."

I have seen even neotropical giant varities (and breed them in captivity)...guess what...they die if not given rotting veg matter...

So, if you have a picture of a sow bug or pill bug activly eating a plant...let me please see it. I am one of those "naturalist geeks" that has actually sat (for up to five hours) with a "convinced" gardener that it is the sow bugs eating there plants...guess what...it has always turned out to be a slug, snail, catipiller, hopper, or some other nocternal villian and the little pill bug is just there eating there other favorite food....poop!

Regards,

j

Nice littel link about "pill and sow bugs."

Hi, Jay....I sent my son a copy of what you wrote here because he has had a huge problem in the past in his greenhouse/cold frame...here is what he says and a picture he found on the web...don't know if the pic will paste from my email....

"... my understanding is that pillbugs-sowbugs only eat green stuff when their population exceeds their preferred food source. I read a bit about it last winter when my greenhouse was overrun. I think they mainly eat early morning and late evening while its darkish, and stay in the shade or barely underground during the day. I saw dozens eating the crowns of my mizuna last winter, wish I'd taken a picture. An image search found this picture, also pillbugs eating strawberries, tomatoes, and plant stems.... "


edit...I'll try the pic again....

Jerry, welcome to the forums! I thought I had noticed this was your first post...good to have you here.

I am not sure what my son ended up doing to beat back the sowbugs but it might have been coffee grounds. Diatomaceous earth didn't work and a few other things...they were a solid thick layer in some places and besides the greenhouse they were in an outside bed eating hostas, totally wiped them out...definitely out of balance but OK now. I'll ask again exactly what he did. Glad the coffee grounds are working.

That looks familiar.

Hi Folks,

I thought this one would get everyone talking... I am glad!

As I said...I am still waiting for "confirmed" photos of them actively eating a green "mature" plant to pieces...here is the important part...by themselves...

I am not denying it may very well be true...and I do know that there are "giant tropical" and "foreign" species that have the larger rasping mouth parts to do it...so yes...isopods (of some species) are confirmed of doing it...even flesh eaters (e.g. the variety that eats the tongues out of Snapper Fish and replace the fishes actual tongue with there own bodies thereby forming a symbiotic relationship...strange but true.)

This little topic of interest is something (as I have said) I have tracked on and off for years. We did find a case of them deforming the skin of young cucumber fruit. and possibly tomatoes that rest on the ground. There may (probably is more) yet...like the photo...which I have seen plenty of, may not be what it appears to be. On microscopic examination of the plant you find (I am still looking and sure I will find more mysteries) the plant has two separate patterns of mastication. It has been even suggested, and there is field observation that have suggested this...that the isopods (pill bugs) are attracted to the "scent trails" left by snails, and slugs...perhaps other insects as well. These are the primary plant destroyers with much larger appetites (and abilities to chew much faster and more efficiently) than the little pill bugs...who get blamed, yet are actually only opportunistic feeders on plants that are already damaged and on there way out.

Now there is some evidence that really small seedlings, just sprouting can be damaged (if not destroyed) by dense populations of them (pill bugs.) That will be more reading and observing...I am sure...as there are so many wonders of nature that capture my attention. So often...like this one though...what may appear as taking place (who knows...in some cases maybe it is??) is something else entirely...

Just food for thought......Isopods, either way, are fascinating and very much part of the Permies ecology of a well balanced garden...

Regards to all, and thanks for reading...

j

I think they mainly eat early morning and late evening while its darkish,

I forgot to add this and thank you for the post...this is actually the time that many animals are active...its called "crepuscular"...and what most "nocturnal" animals actually are....

I wonder if the coffee grounds work because they provide food that the pill bugs actually prefer over green plants? Maybe when they eat plants it indicates a lack of decaying matter in the soil?

Judith...I love your thinking on this...it is mine as well...or one of the hypotheses I have for why coffee grounds work this way.

I can share that my Grandmother put coffee (and tea) grounds everywhere...to solve all matter of issue. It did seem quite effective (plus she said she just like the smell and what it does to soil.) If you really want to impact them (pill bugs) and other insects...look to DE...it works for so many issues...maybe to good. As shared, I like pill bugs (and so do my toads) so for folks tracking this...instead of "chasing little issues" in your gardens (wee crawly things)...take a step back and take a good long gander and think about the ecosystem that is your garden...what is it missing? Is it in homeostasis? If you can't really answer this (at least within the 70% range of understanding it) then you have a much more reading, learning and sharing to do. Our gardens (well my Grandmother's) almost grew themselves when established and she just "played" and "eat" her way through them each year (as did all the "little people" she had around her.)


Regards,

j

I too witnessed the pill/potato bug snacking down on my starts in my raised beds last year. I was also under the impression that they only ate decaying matter. I have a theory for why this might be happening, maybe they're evolving, but maybe they're seeking the calcium in the plants. The reason I think that is because when I was helping my mom on a construction project the dry wall (gypsum) paste was all over the floors and the little buggers were going crazy for it. There were thousands of them muching. Just a theory, but maybe its a sign of calcium difficiency in the soil and other organic matter that would turn them to this behavior. I'm going to try the coffee ground method, thanks for the tip.

I see pillbugs everywhere in my yard. But it is usually on decaying matter under another blooming plant. However, it's been exceedingly dry here for the last two or three months. So the other day I was over checking my compost pile and I picked up a humongous handful of dirt and there was thousands of them all clustered together underneath there in one huge ball. So I'm not sure what they feed on in reality but I know they do like some moisture and also I have found that a lot of my plants this year have been Eaton with holes in the leaves I do not think that they are pill bugs doing it I think it is earwigs what somebody say about that do earwigs eat plants destroy plants or what I'm curious to know somebody's comment thank you

For whatever reason, it's a bumper crop of sowbugs (aka pillbugs, roly polys) this year here on our Central Texas homestead. But we have black soil and a watered garden. The neighbor has dry rocky soil and typically his critters are different over there. For example he gets lots of rattlesnakes but we have not seen one yet here.

The sowbugs attacked our strawberries, so we're trying coffee grounds today. They also infest wherever they can get in thru cracks, such as garage and shop with big roll-up doors that don't seal completely. When I walk around outside in the not-yet-hot mornings, there are several sowbugs meandering per square yard, or more.

I wonder why we have so many. Koyaanisqatsi? In years past, we only had a few, typically hiding in the cool under objects, plants, melons.

Wow this is so interesting! We've had a drought here as well and some little buggies have been after my sprouted beans and corn, but nothing compared to what I expected/got in previous years. I've been watering with diluted urine, coffee grounds, Epsom salts, wood ash, and compost tea and it seems? to be working? Also I haven't had any animals chewing on them and we've had a bumper crop of bunnies and chucks. Suspicious. But I'll keep doing it!

Also usually the slugs gnaw tender melon/squash sprouts down to the ground as soon as they come up, but this year they are completely left alone, completely!! Something must be right...
Makes me wonder though (I'm not too terribly worried, but) the whole thing about "if something's not eating your garden, you shouldn't be either". Is the coffee bad? I personally don't drink it but I'm not afraid of it. Can't be any worse than store veg. But it just got me thinking.

Almond, thanks for sharing what works for you.

It is my understanding from Dr. Bryant Redhawk that soil building often eliminates pest problems:

https://permies.com/wiki/redhawk-soil

Used cofee grounds or new?

Our gardens (well my Grandmother's) almost grew themselves when established and she just "played" and "eat" her way through them each year (as did all the "little people" she had around her.)

THAT, totally touched a heart string with me...My Grandmother had a "green thumb."  What a pleasure it was as a child to nibble at what Grandma grew in her garden...60 years later, great memories... I only hope that my grand kids will fondly remember the great taste of the veggies from Grandpa's garden that were raised from compost and worm poop...Good schtuff!

i had really poor germination rates for my seeds indoors this spring
i was finding seeds uprooted with the tap root eaten
it kept happening so i was checking on them often and found the reason
caught a potato bug eating the sprout red handed...pulled it away from the sprout and found tiny chew marks right where it had been
i always loved potato bugs and have boat loads of them in my indoor garden over the winter... i dont mind them being there although i now believe they are eating new roots
when i start my seeds this coming spring it will be with fresh soil and sealed under a dome to hopefully avoid what happened this year
i still like them and it was interesting to learn that they are crustations

M. Phelps wrote:caught a potato bug eating the sprout red handed...pulled it away from the sprout and found tiny chew marks right where it had been
i always loved potato bugs and have boat loads of them in my indoor garden over the winter... i dont mind them being there although i now believe they are eating new roots

Sorry about the potato bugs.  Did you find that coffee grounds helped?

Hi Jerry, I think I might agree with Jay on this.  Here is the reason…
I see pull bugs in my garden and all over my yard ALWAYS, but have never noticed them eating anything fresh.  They mostly hide under dying stuff.  My new transplants however, get chewed down almost immediately overnight after planting, and I caught the culprit.  It is slugs every single time, they come out at night and are gone by morning.  I tried coffee grounds, but I didn’t go very thick so I have to assume that’s why it didn’t work.  I will try again

Hi Anne,
i am just hearing of this technique now... but i may give it a try next spring... and with the potted plants over the winter
in the garden i use wood chips and coffee grinds (thanks Dr Redhawk) and the millipedes have been multiplying like crazy in there
i do see potato bugs in there as well to a lesser extent