In case you need a refresher course, here are some points about the benefits of using compost in your garden, according to the UC Master Gardeners of Alameda County:
⢠Improves Soil Structure (Tilth): Lightens heavy clay soils and adds structure to sandy soils.
⢠Saves Water: Increases the water-holding capacity, reducing runoff and water usage.
⢠Feeds Plants & Soil Life: Adds slow-release nutrients and boosts beneficial microorganisms and earthworms.
⢠Balances pH: Helps to buffer and balance soil pH (acidity/alkalinity).
⢠Reduces Needs: Lowers the need for commercial soil conditioners and chemical fertilizers.
⢠Protects Plants: Encourages healthy root structure, helps control erosion, and acts as a mulch to reduce weeds and moderate soil temperature.
**How to Use Compost **(UCANR Recommendations)
⢠As a Soil Amendment: Mix 1â4 inches of compost into the top 6â10 inches of soil before planting.
⢠For New Beds: Apply 3-4 inches of compost and turn into the soil.
⢠As Top Dressing/Mulch: Apply 1-3 inches around established plants, trees, and shrubs (keeping it away from the stems).
⢠For Lawns: Spread a 1/2 inch layer of compost over the lawn in the spring.
⢠When to Apply: Fall is best for improving soil structure, but it can be applied in spring to prepare for planting.
⢠Materials: Composting kitchen and yard waste helps prevent landfill waste and acts as a nutrient-rich fertilizer.
For the Snarkies among you who answered, âAnd compost mulch provides a place for cats to poop.â Hey! Get your head out of the toilet. We covered how to thwart that in a previous newsletter.
But if you think composting is a lot of work, what if I told you that you can make compost using just two ingredients, and you donât have to turn the pile, ever!
Now that I have your attention, hereâs what Kellie Hallenbeck and Judy McClure had to say in a recent Sacramento County Master Gardener newsletter:
âThe average person in the U.S. consumes about three cups of coffee per day, with landfills receiving 75% of those spent coffee grounds. Deep in landfills, grounds are robbed of oxygen, so they cannot decompose aerobically like they do in a compost pile or worm bin. Instead, coffee grounds are subject to anaerobic decomposition that can produce large amounts of methane. Methane is a greenhouse gas contributing to global warming, 25 times more potent than carbon dioxide.
Composting with coffee grounds is easy if you remember they are high in nitrogen and considered green for compost purposes. Just add a good supply of carbon-rich material, like dried leaves and shredded paper. Too much nitrogen can cause the release of ammonium gas and cause foul odors. At the same time, too little nitrogen will slow down the decomposition process.
Follow your routine of food scraps and grass clippings by mixing 1 to 2 volumes of âbrownsâ (dry, woody materials) to 1 volume of âgreensâ (moist, green materials, filters with grounds). Add water and turn the mixture to add air.â
(Or, donât turn. Read todayâs podcast transcript interview further on in this newsletter (or listen to it, above) with Master Gardener and composting expert Susan Muckey to find out the why and how).
âIn 2022, the Compost team experimented using only coffee grounds as the âgreensâ and dried leaves as the âbrownsâ to see how the final product compares with traditional methods. Too many coffee grounds were added, resulting in the pile being too wet. The Compost team is trying again with a bin made of a hog/chickenwire ring. The pile was demoed at the March 2026 Open Garden.
[During you next FOHC visit], stop by the Compost area to check on the process.How can you help to keep coffee grounds from entering the landfill? Take a bag (or 2 or 3) for your home garden during
[Open Garden Days].Small changes add up over time. Just think: by adding grounds to your compost, you will be reducing waste and protecting our environment, all the while having your coffee too.â
A 4âĂ5â sheet of 6-inch Concrete Reinforcement Wire (CRW) wrapped end-to-end forms a cylinder roughly 19 inches across and 4 feet tall â plenty of structure to hold a seasonâs worth of material while letting air reach the pile from every side. The wire ends along the seam can be secured with several zip ties through the opposing squares to lock it shut, so no special tools are needed (and you can pop it open to turn the pile, if necessary).
The chicken-wire or 1/2â hardware-cloth liner goes on the inside of the Concrete Reinforcement Wire cylinder so itâs held in place by the pileâs outward pressure rather than fighting it. That fine inner layer keeps loose material from spilling through the big 6-inch openings while still letting the whole bin breathe. Inside, layers of browns (shredded leaves) and greens (coffee grounds) are alternated, a 3 or 5 gallon bucket of each at a time, until the bin is full.
The 2-inch perforated pipe runs straight down the center of the bin, poking a few inches above the top of the pile and reaching all the way to the ground. Holes drilled in a staggered pattern along its full length to more easily water the middle of the pile with a garden hose. The holes also let oxygen drift into the middle of the heap â the spot that otherwise goes anaerobic and slows down the composting process. PVC, ABS, or even a length of corrugated drain pipe all work; just drill 1/4â-3/8â holes every couple of inches around the pipe and cap or screen the top so it doesnât fill with debris.
We Talk with Sacramento County Master Gardener and compost expert Susan Muckey.
Farmer Fred:
[0:00] Did you know the average person in the United States consumes about three cups of coffee per day?
Problem is, landfills are receiving about 75% of those spent coffee grounds. And those coffee grounds are buried deep into landfills, and then the grounds are robbed of oxygen so they canât decompose. And what happens then, they become anaerobic and poof, they produce large amounts of methane. Methane is a greenhouse gas contributing to global warming, 25 times more potent than carbon dioxide. Did you know you could use those coffee grounds instead of sending it to a landfill? Put it in your compost pile. In fact, you could even make a compost pile using nothing but coffee grounds and leaves. Does that actually work? It just so happens they tested that here at the Fair Oaks Horticulture Center. Weâre here at a workday where the Sacramento County Master Gardeners are hard at work, and weâre talking with Composter Supreme Susan Muckey, Master Gardener. And Susan, you did a little experiment back in 2022 on this.
Susan Muckey:
[1:08] Yes, we did. It was great. We took the tomato cages, which were pretty big tomato cages. They werenât like the little skinny ones. And then we put chicken wire around them, and we started this in November. And actually, if I were to do this again, I would probably start it as early in the fall as I could, especially as soon as I have enough leaves to fill up a tomato cage. And then the hunt begins. You can go to Starbucks or some of the other places if you donât drink coffee. And just use, I would say, 50-50 ratio of coffee grounds and leaves. And what happens is by six months, if it rains, and if it doesnât rain, youâre probably going to have to water it a little bit. But if it rains, youâre going to have incredible compost. The most beautiful I have ever seen.
Farmer Fred:
[2:02] Letâs talk a little bit about the tomato cages you used. I think weâre standing next to one of them. That was probably a prime candidate for that project. And this is made out of concrete reinforcement wire. And those sheets are usually four by five or thereabouts, maybe four by six, and just formed into a circle. Sometimes theyâre secured by zip ties. Sometimes people will bend the prongs together to secure it. But it gets you a tomato cage, six-inch mesh, thatâs about five feet tall. and probably two feet wide. So thatâs the size you want. And then you would wrap the outside of this with chicken wire.
(FREDNOTE: others who have done this recommend putting the chicken wire or hardware cloth on the INSIDE of the tomato cage.)
Susan Muckey:
[2:40] Yes, because, well, I decided to do a beta test. And when we did it, and this is not in front of an audience, but we did it and we poured the leaves in. And guess what happened? All the leaves fell out. So then we said, oh, well, we probably need to put some chicken wire around it. And I find, too, that shredded leaves probably would work better than the regular leaves. And if you donât have a leaf shredder, your lawnmower will work just as well.
Farmer Fred:
[3:13] I use my mulching mower for that. And I also use my weed whacker. And Iâll stick the leaves in the fall into a metal trash can. Remember 32-gallon metal trash cans? Well, theyâre still around. And just put my string trimmer into that and cut them up, and it works fine. And in this day and age, you can save those leaves forever if youâve got a big enough compost sack where you can just keep those leaves in until you need them.
Susan Muckey:
[3:47] Yesterday, I shredded five bags of leaves from last year and they were fine. The only problem is if you hadnât shred them in the fall when you collected them, itâs very hard to shred them. Theyâre like a mass of muck. And so I could just take the top layer because those shredded just fine. But the bottom ones, because I think during the year, what happens is the moisture thatâs in the leaves kind of goes down to the bottom, and now youâve got all this moisture, even though the leaves were dry when I put them in the bag.
Farmer Fred:
[4:23] âMassive Muckâ was the name of my band in high school, in case you didnât know. The secret to a successful compost pile is a 50-50 mix of what are called greens and browns. Those fallen leaves, theyâre browns. And Iâm still trying to wrap my head around, how can coffee grounds be green?
Susan Muckey:
[4:40] Because theyâre a source of nitrogen. And actually, once theyâve gone through the process of making coffee and brewing and whatnot, they are no longer extra acidic. Because thatâs what people are afraid to use, coffee grounds, because they think theyâre too acidic. But once youâve processed them through the coffee-making process, I use instant coffee, so I donât have that problem. But anyway, yeah, they will not be acidic.
Farmer Fred:
[5:08] How do you stack them when youâre adding green, when youâre adding brown? How big is each layer?
Susan Muckey:
[5:16] Okay, so what we did about a month ago, two months ago, is I did an interactive mini talk with my audience. And after I talked a little bit about compost and the components of compost, we went over to our trusty tomato cage and I had each one of them dump a bucket into it, of alternating leaves with coffee grounds.
Farmer Fred:
[5:40] Five-gallon bucket?
Susan Muckey:
[5:41] Well, some of them were five-gallon. I think the coffee ground buckets were smaller, like maybe the three-gallon ones from Loweâs and Home Depot. And they all, one at a time, did it. And then we had somebody sitting there with the hose watering. It became their compost pile. And then we did a cheer when we finished it.
Farmer Fred:
[6:01] Now, of course, the secret to a successful compost pile is also air. So do you have to turn that pile?
Susan Muckey:
[6:08] No. Thatâs why itâs called a no-turn compost pile. And what happens is the materials you put together, they all start interacting with each other. And pretty soon, within about six months, youâre going to have compost.
Farmer Fred:
[6:22] Well, probably below what you can see on top. So the compost takes up how much of the bottom of the tomato cage?
Susan Muckey:
[6:28] Okay. So when we did the original experiment, I kept looking at the tomato cage and it still looked like nothing had happened, only that it had shrunk. It went to about half the size. And I said, okay, well, Iâm tired of waiting. So we tipped it over and the outside was still the leaves because we didnât turn it. But what came out of it was to die for. Even Farmer Fred would die for it.
Farmer Fred:
[7:00] Having a smart pot compost sack, I know that story well because I fill it with the shredded leaves and you look at the top and you go, nothingâs happening there. But then if you dump it out, all of a sudden thereâs all this beautiful brown and black compost.
Susan Muckey:
[7:15] Thatâs right. Thatâs right. Thatâs exactly right. And I donât remember because it was several years ago, four years ago, but I donât remember if there was any worms in there. I canât really remember if there were, but if there were worms in there, they probably would have aided in the decomposition process.
Farmer Fred:
[7:32] Now, obviously youâre using, if youâre using a three gallon bucket of coffee grounds, thatâs probably more coffee than youâre going to make in a week, making your 10 cups (!) of coffee each day. So a lot of coffee shops will gladly give you a big bag or two. And that happens here at the Fair Oaks Horticulture Center. But is that just for Master Gardeners or anybody who shows up on an Open Garden day?
Susan Muckey:
[7:53] I think itâs for anybody. And actually, what Iâve done is if you give one of the coffee shops a five-gallon bucket, theyâll fill it for you.
Farmer Fred:
You just have to have a lid.
Susan Muckey:
Yeah, it should have a lid or a three-gallon if you canât carry five gallons. But I find they donât necessarily want to keep a lot of coffee grounds around. Now Starbucks, I know theyâll bag it up for you, you know if youâre really a true gardener you donât want like just a little bag of coffee grounds you want a manly size bag of coffee grounds. theyâll say âOh do you want us to put it in little bags?â and iâll say âNo just give me a big bag.â âCan you carry it?â âYes i can carry it.â
Farmer Fred:
[8:38] How big is the big bag?
Susan Muckey:
[8:39] Itâs a garbage bag oh okay itâs probably a good 30 pounds.
Farmer Fred:
[8:44] You can drag it to your car.
Susan Muckey:
[8:45] No i wouldnât want to drag it to my car, leaving A trail of coffee grounds.
Farmer Fred:
[8:51] You know. Well, itâs in a garbage bag.
Susan Muckey:
[8:53] Yes, itâs in a garbage bag, but as youâre dragging it. And also, you do not want it in your car. You know, coffee grounds all over your car.
Farmer Fred:
[9:03] How do you get it home?
Susan Muckey:
[9:05] I do carry it in my car, but it doesnât have a hole in the bag. All right.
Farmer Fred:
[9:10] Well, use two garbage bags, one inside the other.
Susan Muckey:
[9:14] Yes, yes, yes. And I do try to take it out as soon as possible because my husband always says, your car smells like a garden.
Farmer Fred:
[9:22] Well, thatâs putting it politely.
Susan Muckey:
[9:24] I know. He says, between the compost and all the other stuff you put in here, he doesnât ride with me very often. Okay.
Farmer Fred:
[9:31] Well, my car usually smells of chicken manure and things like that. All right. So if youâre working with a converted tomato cage that is like five feet wide by two feet wide, If you went to get enough coffee grounds to fill up, say, half of it, it would probably be, and if itâs a garbage bag full, youâd probably need about two or three of those garbage bags.
Susan Muckey:
[9:58] Yes, itâs quite a bit. And you have to realize, too, when you putâŚ
Send this story to anyone â or drop the embed into a blog post, Substack, Notion page. Every play sends rev-share back to Beyond The Garden Basics.
70% to the publisher ¡ 20% to whoever forwarded this ¡ 10% keeps Storyflo running.
Loading comments...