100 bags of leaves... now what?

I have collected upwards of 100 bags of leaves from the city-folk who give away this precious material for free. I also have a steady stream of coffee grounds from the local coffee shop (~70 lbs/week). My goal is to create as much compost as I can in order to use it in the gardens come springtime. However, being in north central Wisconsin, it is getting to the point where winter will come quick (the fact that there is not any snow on the ground yet is just short of a miracle). Should I get my leaves all shredded and piled now, and let them and the grounds sit until spring? Should I shred and leave them in bags to make compost as the coffee grounds arrive? What is the best path forward to be able to have copious amounts of compost come springtime?

The sooner you can shred them, the better.  Leaves don't break down for a very, very long time if you don't shred them.  They mat together and stay put.  At one point, I made a double-dug garden and incorporated a bunch of Oak leaves.  Three years later, I dug into the soil and found whole leaves looking much like the day I put them in the ground.

If it were me, I would shred the leaves and mix in the grounds right now.  You may have good compost by time to plant.  I don't plant until the last week of May normally here, but your leaf/coffee ground mix will start composting before then.  I would start turning the pile as soon as you are able break it apart in the spring.  Keep the moisture correct and turn it every week, and you should be okay.

There's an old saying: There's no better day than today. Shredded leaves decompose much faster then whole leaves. Shred those leaves soon and get them into a pile. Here's the thing- If you put just leaves into a pile, you'll have leaf mold after a year or two. Leaf mold is quality stuff. If you want compost to use by spring, you'll need to add a "green" to the leaves, something that has nitrogen in it. Grass clippings are a great source of nitrogen, but of course today being December 1st, grasses have gone dormant here in north america and aren't growing. Good news, your coffee grounds contain nitrogen. Put your shredded leaves and some coffee grounds into a pile, a big pile, like the size of an automobile or bigger. Once active composting starts, that pile will shrink, quite fast actually. Stir that pile to incorporate more oxygen, and it'll shrink again. Do this regularly, and I'm willing to bet you can have a usable compost for your garden come spring. Having a long probe compost thermometer is a great tool to let you know how hot the pile is in the center, and as the temperature drops, can guide you on when to turn the pile or add more nitrogen.

Alright. I will get them shredded and piled this weekend. The coffee grounds only come about once a week, so can I just make a pile of leaves now, and then once a week, dump a bag of grounds into it? It may take a while to get to the right C/N ratios, and will prove difficult once it gets super cold/snow covered. Or should I just shred and pile the leaves now, and then stockpile the grounds in a shed until everything starts to thaw in the spring?

I don't think you're going to be able to make much compost between now and spring given cold temps and lack of nitrogen. Shredding 100 bags of leaves is a big task. Given that youre going to spend a lot of time with little chance of achieving your goal, why not rethink the whole endeavor?  If it were me, I would not shred the leaves. I would make a large pile and come back In a year or two for the resultant leaf mould. You could compost it at that time or simply use it as is.

O. Donnelly wrote:I don't think you're going to be able to make much compost between now and spring given cold temps and lack of nitrogen. Shredding 100 bags of leaves is a big task. Given that youre going to spend a lot of time with little chance of achieving your goal, why not rethink the whole endeavor?  If it were me, I would not shred the leaves. I would make a large pile and come back In a year or two for the resultant leaf mould. You could compost it at that time or simply use it as is.

If you don't shred the leaves, in a year or two you are going to have leaves.  Last fall I shredded, loaded, hauled, and piled 120 bags of leaves in less than 2 hours.  I still don't have leaf mold, although the leaves made really good mulch where I put them.

You aren't going to get compost during these winter months, but the first couple months of spring, composting works here.  That should be enough time to get compost for planting given enough turning.

There is no harm in having them shredded now.  Shred it while, and when, you have time, and use it when you have the right conditions (nitrogen and warmth), since microbial life prefers warmer temps.  

That said, you can still make compost in the winter.  It does require that you have the proper C to N and water ratios; the warmer your water is the better.  If you do not have the right conditions and ratios, the compost will only heat up in those small pockets where the ratios are right, and that wont have the cumulative effect that creates a good hot proper compost.  If you had buckets upon buckets of coffee grounds to create the right ratio right now, I'd say definitely go for it.  Without a nitrogen source, you are largely just going to have shredded leaves breaking down into leaf mold (which isn't terrible), but there is only so much heat that can be produced so the amount of decomposing will be greatly decreased during the winter.  The leaves themselves have some nitrogen, however, and enough bacteria and fungi on them to do something, with or without the coffee grounds.  

If you decided to shred it all now, and try to do a smaller compost with the amount of grounds that you have at present, you are likely going to get at least that much compost by spring, assuming you turn it appropriately.  

One thing to do is to cover the pile with a tarp; this traps heat.  You could pile the rest of your bags around and on top of the smaller heap, thus insulating it.  Then in the spring, make compost tea with this first batch, and utilize it as you like over a broader area or to feed nursery seedling stock, while accumulating enough compost for the rest of the garden come warmer weather.  

According to Jean Marc Fortier, author of The Market Gardener, the type of microbial nutrient boost that comes from compost does not activate fully first thing in the spring anyway: "The fertilizing action of compost is gradual and especially slow in cool spring soils."  He uses dried pelletized chicken manure for early spring nutrient bursts.  He loves his compost, but stresses that there are huge differences in quality by how it is made.  If compost is made properly it stabilizes nitrogen and trace nutrients allowing these to slowly release from their carbon bonds over years, which is quite unlike manures, which give a rapid boost, or poorly made composts which largely add only organic mater to the soil.

You aren't going to get compost during these winter months, but the first couple months of spring, composting works here

Perhaps this is your experience, Todd, but a friend in my valley said her husband made hot compost at minus 30C using leaves and fresh rich barn bedding from the cattle shed; he'd mistakenly not put much bedding down and so there was a need to clean the manure out of the shed and put a better ratio of bedding down.   It might be a bit better to start the process in the fall when things are still decomposing readily naturally; I imagine the turning process must be timed perfectly as you would not want your compost to cool down too much, as this would deter the process and make turning it difficult.

People keep telling me that Roberto, but I certainly don't know how.  We have had unusually warm weather so far this spring and my bins have already stopped dead.  I went to the place I normally get my wood chips.  These are huge piles, 15 or 20 feet deep and probably 40 feet across.  Earlier in the fall I would see the piles steaming when I went to get chips.  I broke thru the crust on top and dug in a couple feet and there is no heat whatsoever.  Maybe if I could dig all the way to the middle I wood find some warm spots, I don't know.  I do know that I have never successfully kept a pile going later than late fall, no matter how big it was.  If you water a normal sized bin here, say 4 ft x 4 ft, you will very quickly have a 4 ft x 4 ft block of ice.  If you water it with warm water, it will take an extra half hour to get your block of ice  

HI Todd,

I went to the place I normally get my wood chips.  These are huge piles, 15 or 20 feet deep and probably 40 feet across.  Earlier in the fall I would see the piles steaming when I went to get chips.  I broke thru the crust on top and dug in a couple feet and there is no heat whatsoever.  Maybe if I could dig all the way to the middle I wood find some warm spots, I don't know.

 I don't doubt this.

Woodchips especially damp ones, have a certain breakdown going on (when the moisture, oxygen, and temperature are in the right proportions), but this is limited due to a primarily chemical  (oxygen/carbon) reaction (a bit about this process here); this chemical reaction quickly takes over from the biology in a wood chip pile.  This, in my understanding, is not at all comparable to a properly built thermophilic biological compost, where those chips would be combined with other materials in the proper composting ratios to increase the nitrogen to the point of full biological interaction with the carbon.  Here, the biological reaction along with the chemical reaction are responsible for the heat, but it is primarily the thermophilic (heat loving) bacteria that do the job.  

Woodchips, however, are, on a unit by unit basis, inherently too small of a surface area/to volume ratio to create compost quickly and effectively enough for longer term composting heat generation when external conditions decrease in favor-ability, thus full biological interaction with the carbon can not occur, even if the proper ratios of nitrogen are layered properly with the chips(some will occur certainly, but not involving the full thickness of the chip's volume, and this is the reason that Mother Earth News initial experimentation with wood compost heat generation failed.); this is the reason that Jean Pain had invented a shredder to make his woody material have a much higher surface area to volume ratio; thus oxygen and moisture and nitrogen could reach the majority of the woody surface and gain nearly full biological activity; this is one of the reasons that leaves don't break down well without shredding besides the layering effect you mentioned; the surface area that is exposed to the composting elements in a shredded leaf is massive in comparison to a intact leaf.  

Pain ensured that his woody waste was balanced with green material and moisture so that it composted effectively over an extended period.  I know that Pain was working in France's south, and it's climate is not comparable to a winter in your or my area.  That is why tarping and insulating a pile are potentially of utmost importance, and the size of the pile would certainly make a huge difference.  Pain's piles were massive (15 tons), and produce heat for 2 years.  Our own winter situation would require that the pile not be an average 4' X 4' pallet framed heap.  It would likely have to be larger, and it would likely have to be insulated quite a bit if it weren't.        

It's 20degrees F and clearly winter in this video by Ben Falk.  It's clear in this video that the heap was not built in the winter, however.  Note that the heap was insulated on the outside by a surrounding support wall of square bales.  Falk's compost water heater.  I haven't seen an update on this video or this project.  

Roberto pokachinni wrote:It's 20degrees F and clearly winter in this video by Ben Falk.  It's clear in this video that the heap was not built in the winter, however.  Note that the heap was insulated on the outside by a surrounding support wall of square bales.  Falk's compost water heater.  I haven't seen an update on this video or this project.  

I can see it working that way, with that much insulation.  I can't see it being cost effective to do it just to make compost though, unless you get your straw bales much cheaper than I can.  A rough guess from looking at the video is 80-100 bales.  That would cost me $240-$300.  If I was heating my water with it, it may be worthwhile, but it isn't to make compost.  Especially when I can just wait and make it during the summer

I don't have a great answer for you but if I were in your shoes, I'd shred them now (before it gets cold on Tuesday).  I'd take some of the shredded leaves and mix in whatever coffee grounds you have in approximately the right ratio to start the core of the pile.  Moisten it down to the "wrung out sponge" level, ideally with warm/hot water.  Then mound all the rest of the leaves on the top and sides as insulation and cover it with a tarp.  As you get more grounds you can remove the tarp and try to mix them in with a pitch fork.  Or just save them till spring.

For this batch, I'd put them in a sunny place so the pile thaws out sooner in the spring.  Then turn it as soon as you can, mix in the coffee and turn it every couple days.  For composting in the summer it may be better to do it in the shade.

I'm up North of you in Thunder Bay. I have used used coffee grounds before, but I had to stockpile them frozen through the winter because I needed a critical mass off the stuff to get the pile working, and prevent it from freezing.

Last winter I did that with about 400lb of used coffee grounds, some sawdust, dolomite lime, and water. I also put composting worms in there to see if they would survive. I then surrounded the pile with straw bales, and covered the lot with a tarp.

In the spring the outer parts were frozen, but the core was OK and the worms survived. Then it restarted in mid April when the thaw came. By the time June rolled around, it was still composting, but cool enough to plant the zucchini in the top of it.

Based on my experience, adding the coffee grounds to the pile as you get them might not work as you expect. It may just freeze solid, and then activate in the spring.

Todd Parr wrote:

O. Donnelly wrote:I don't think you're going to be able to make much compost between now and spring given cold temps and lack of nitrogen. Shredding 100 bags of leaves is a big task. Given that youre going to spend a lot of time with little chance of achieving your goal, why not rethink the whole endeavor?  If it were me, I would not shred the leaves. I would make a large pile and come back In a year or two for the resultant leaf mould. You could compost it at that time or simply use it as is.

If you don't shred the leaves, in a year or two you are going to have leaves.  Last fall I shredded, loaded, hauled, and piled 120 bags of leaves in less than 2 hours.  I still don't have leaf mold, although the leaves made really good mulch where I put them.

You aren't going to get compost during these winter months, but the first couple months of spring, composting works here.  That should be enough time to get compost for planting given enough turning.

I believe everyone's post here are honest and written from direct first hand experience.  I'm sure that what you describe above has been true for you. I just checked my leaf pile, so that I could speak out of direct experience rather than out my arse.  Here's what I found...

I built my leaf pile in oct 2015, so it is 2 years old. It was 8' diameter, 3' high woven wire fencing packed as full as I could get it with newly fallen leaves after a rain.

Now the pile is about 12" thick. The top .5 cm or so is recognizable leaves, but below that thin veneer - I wouldn't even call it leaf mould. It is soil, forest duff, not sure what you would call it. There are no recognizable leaf parts whatsoever.  Completely decomposed.

My climate is slightly warmer than yours (5b) and the pile is in the forest, with an intact sfw capable of rapidly decomposing leaves. Perhaps that's the difference in our experiences...