How fresh do grass clippings need to be for compost?

[hooseykins]

So I’ve had good luck with using grass clippings for compost here recently. We just bought our first house and had our first garden this year and are working to make more compost for the raised beds we are adding for our next growing season.

I don’t need to know how to make compost with the clippings as I believe we have that figured out.

but something that I haven’t been able to find an answer to is how old can the clippings be. Do they lose their nitrogen content over time? I plan on collecting a good amount of clippings while my grass is still growing to hot compost with leaves this winter but wasn’t sure if they wouldn’t work after they have sat and lost their color. Anyone have input on this? Thanks!

 

[DirtMechanic]

Sugar. Starches are more prevalent in the green wet stuff. You know you cannot live without starches and proteins right? Neither can the soil, and for the same carbon based entity reasons as you. In ag they talk about amino acids but thats what comes from protien breakdown. Welcome to the club. It all composts of course, old and dry as well.

 

[headfullofbees]

If you are composting JUST grass clippings, it will have a tendency, because they tend to be so soggy, of keeping out air, leading to anaerobic decomposition.
Your old, dry clippings will help to mitigate against that, but you really could do with two things:
1)Material of bigger structure to help with aeration, like twigs etc.
2)Browns: compost is usually considered best when a mix of greens & browns, & in my view, the best additives are leaves and paper or brown cardboard, as worms love the cellulose in these, & their gut bacteria are beneficial to soil/compost.

 

[Mr_Yan]

late to this party but...

will they lose the nitrogen - yes. Nitrogen is fast to volitize out of the soil / compost - so fast that many say not to pay much attention to the nitrogen numbers in soil tests as they swing wildly by season.

If you have just clippings and not a bunch of seed heads from the lawn you could use them as a layer of mulch over the garden soil and let them compost in place. Apply the clippings less than 2 inches thick. Then as the fall leafs come down mow over them and mulch the garden in with those. I've stacked fall leafs 12+ inches thick as mulch in the fall and it will lead to GREAT garden soil over time.