Compost Booster

Asked January 2, 2020, 1:44 PM EST

Greetings. My latest composting pile is only heating to about 80 degrees. The previous pile heated to 140F, I assume because of the fresh grass mixed in. I suspect the low temp is due to the fact that the pile is mostly fall and winter leaves (with fruit and veg scraps) but almost no grass. My ratio is way off. So, is there another source of nitrogen I can use during the winter? Or is there a nitrogen supplement I can purchase and mix in with the tree leaves to get the temp up? I am trying to achieve a hot pile so the pile will be broken down by Spring/Summer. Thank you,

Charles County Maryland

5 Responses

It's typical for your compost pile temperature to lessen during the winter. The good news is that microbes are still working, albeit slower, even at about freezing temps.
We don't suggest mixing the pile in winter, which heightens heat loss.
We recommend that you wait until March or April, and then aim to accelerate the process by adding some compost or a small amount of fertilizer. Organic N sources include cottonseed meal and blood meal.

Here is our compost page that discusses more, including ratios and other sources of 'green'/N inputs. (For instance, fresh kitchen waste):


Thanks for the response. My intention is to have decomposed compost ready for use by Spring, so I was wondering how to speed up this process during the winter. With a compost pile of leaves only it will break down very little until I can add grass clippings. I have experienced this in the past. Also, considering I have a zoysia lawn, I wont cut the lawn until May, so clippings wont be available until then.Plenty of grass in the summer, but no leaves. Plenty of leaves in the fall but no grass. So, does the U of Md still collect leaves from College Pk, Greenbelt, and Berwyn Heights, and create leaf gro? How do they break down all these leaves so fast? What are you guys adding to the mix to break your compost down so quickly?

Composting in the winter does not happen quickly. Even adding nitrogen will not help. The pile should not be less than one cubic yard. You will have to be patient. If you want compost in the spring, you will have to buy it.

Maryland Environmental Service is a commercial operation involved in composting yard waste not the University of MD. Their composting operation is slower in the winter as well. Take a look at the publication from Cornell about tips for composting in the colder months


Hello Marian,
I was hoping there was something I could add to my leaves to speed up the composting during the winter, but now I understand there is no such product. Interesting circumstances that there is only a short window in the Fall when I can collect both leaves and grass clippings. Outside of that window I have excess of one and not enough of the other. Oh well... Thanks for the correction on the commercial operators for the composting. Years ago I spoke to a Director of /maybe/ the Ag department at UM. He was the guru for composting so I assumed it was a UM operation. The link you provided offered some pointers, so thanks, and thanks for the response.