Take the 2-minute tour ×
Gardening & Landscaping Stack Exchange is a question and answer site for gardeners and landscapers. It's 100% free, no registration required.

We have a compost bin to which I've been adding kitchen scraps (and some garden waste) over several years. I have never used the resulting compost (mainly because I have a ready supply of horse manure which is easier to work with). Why we still add to it, I don't know. Just habit maybe.

The bin never fills right up because the base material just keeps compressing and rotting down.

Is this compost now better than ever or is the stuff at the bottom now too far gone (is "too far gone" even possible with compost?)

share|improve this question
3  
In the big scheme of things, it is better to put your kitchen scraps in a compost bin than to put them in the local land fill. –  winwaed Jun 9 '11 at 17:05
add comment

2 Answers

up vote 17 down vote accepted

I don't think "too far gone" is possible. If it gets too anoxic then spreading it out on your beds and giving it a day or so to aerate will fix that.

Eventually all the carbon will reduce (=>peat/lignite) in low oxygen conditions; or oxidize (=>carbon dioxide) in high oxygen conditions.

share|improve this answer
1  
thanks. your science is a little over my head but it lends authority to your first sentence - which i can understand, and accept :) –  Tea Drinker Jun 9 '11 at 22:21
    
I come from a geological background so my time scales are not necessarily horticultural :-) I also tend to think low oxygen => lots of carbon => peat/coal/lignite/oil / black rock. –  winwaed Jun 9 '11 at 23:22
add comment

It may not be "too far gone", but both nitrogen and phosphate are rather easily leached out. A compost pile that you've allowed to sit for years is probably rich in humus (think forest floor) but potentially lacking in certain macronutrients. "Better than ever" is unlikely if the pile has been rained on.

Do you let your horse manure rot for a year or so before you use it? What are you using for bedding?

You may not need or want to build a separate pile for your kitchen scraps and garden waste. My experience with horse manure is that the combination of bedding and manure actually has a rather low nitrogen to carbon ratio. When our kitchen scraps don't get fed to the chickens, I dump them into onto the manure pile -- either before the day's deposit, or inserted into a hole a couple of feet deep into the pile and then re-covered. The kitchen scraps break down very fast in that environment, and the extra N from the kitchen helps speed up the manure breakdown too.

share|improve this answer
1  
Good point about leaching. I've been doing some preliminary reading on rainforest soils and those are very poor because of leaching by rain and humic acid. So much so that the soils become orange/red due to the iron & manganese that is left behind. I have a book on the table waiting to be read on this subject... –  winwaed Jun 12 '11 at 18:59
    
@winwaed - what's the book? –  bstpierre Jun 12 '11 at 19:29
    
It is a text book on soils - more geology than horticulture. "Soils Genesis and Geomorphology" by Schaetzl & Anderson, CUP. I have a possible research project for undergrads on volcanic ash layers in Costa Rica - but I need to understand how the soils build up/change. We found the ash layers last month - project website is at: ecomapcostarica.com –  winwaed Jun 12 '11 at 19:37
1  
You mean that the horse-manure-plus-bedding doesn't have that much nitrogen - correct? If so, you said it backward - either it has a high carbon to nitrogen ratio, or a low nitrogen to carbon ratio. –  Ed Staub Sep 8 '11 at 14:49
    
@Ed: good catch, thanks. –  bstpierre Sep 8 '11 at 15:50
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.