Peanut hulls as a mulch? Good or Bad?? : LUSENET : Countryside : One Thread

I posted a question about fertilizing existing plants and got some great suggestions that I did not know about. Thank you all for taking the time to answer my silly questions. I learn so much from you all.

One thing that was pointed out is that the peanut hulls that I am using are low in nitrogen. I am only using the peanut hulls as a top mulch (to prevent weeds and help keep moisture in the ground) so far. I was going to turn them into the ground in my rows in the fall with some other compost as well. Is that a bad idea - turning them into the soil? Are they OK as a top mulch or will they still rob the soil of nitrogen?

-- Rebecca (, May 04, 2002


You might want to look at some other composting sites also, but this one states that peanut hulls are considered more of a carbon source than a nitrogen source: Composting, North Carolina Univ., ml

"The C/N ratio significantly influences the rate and degree to which a mixture composts. Microbes use carbon as energy and nitrogen as a food source to produce proteins. Optimum C/N ratios range from 20-30 parts carbon to 1 part nitrogen. C/N ratios under 20:1 result in incomplete nitrogen use allowing ammonia to form in the pile and be released during turning or aeration. Animal manures, poultry litter, urea, grass clippings, legume residues and some sewage sludges are good sources of nitrogen. Wood shavings, straw, peanut hulls, and newsprint have high carbon contents."

-- BC (, May 04, 2002.

If the peanut hulls are turned under they will decompose, i.e. bacteria and fungi will convert the hull carbon into more bacteria and fungi. In this process the microbes will need nitrogen, phosporus and everything else that greeen plants need to grow. Life is life. Later, earthworms and other animals and microbes will eat the original bacteria and fungi and return the nitrogen, phophorus, etc. to the soil. If the decomposition and green plant growth take place at the same time, the plants will lose out to the microbes. In that case you will have to fertilize to swamp out the needs of the microbes. If decomposition and plant growth take place at different times, e.g. decomposition in the fall-winter-spring and plant growth in the spring-summer-fall, then there should be no problem. These aare not hard-and-fast, by-the-numbers types of processes but are dependent on temperature, moisture, soil condition, etc. The hulls themselves do nothing to soil nitrogen. It is the microbes that break them down that need the nitrogen. The biology and ecology within soil is a fascinating process. Hope this helps.

-- MartyB (, May 04, 2002.

I'm not a soil sciencitist by any means or an expert on their theories but can tell you from alot of years of practical experience that almost anything organic [hay,sawdust,manure etc] that you add to the soil will help it produce a crop.If you need N then get some organic fertilizer of some type top dress.The more you work your soil and the more organic matter you add the quicker anything you put on will break down into soil humus.I do all my composting in the garden or truck patch by sheet spreading the material and discing or tilling it into the soil then it quickly decomposes because everything for the decomposition process is already present.I realize this is contrary to alot of expert theory,but will put my soil in my garden and the quality of the vegetables up against anyone's. The quality of the plants you grow and the quality of their fruits is the ulitimate soil test.

-- Gary (, May 05, 2002.

If you till in JUST the peanut hulls, they suck the Nitrogen out to decompose, and your plants look yellow and don't yield worth a flip. Add Nitrogen from some source.

We know this because we tried rice hulls, and the garden took more than a year to recover.

-- Rose (, May 05, 2002.

AND..until they decompose, they hurt when you walk on them...BUT...I'm one of those barefoot gardeners.....

-- Harmony (, May 05, 2002.

If you are going to add additional compost and turn the whole thing under for the winter you should have no problem. The peanut hulls will use up nitrogen WHILE they are decomposing but this process should be completed by spring and the nitrogen will then be available again. Just add plenty of manure and you'll be fine. In the meantime the peanut hulls are fine for top mulching.

-- Elizabeth (, May 05, 2002.

In the long run the peanut hulls are good.

As others say, while decomposing they will take N out of the soil, and your green plants will suffer.

I assume you plan on continuing the peanut hull mulch every year? I also assume you are living in a warm southern climate (where peanuts grow)and you could turn the mulch under in fall and it would do a lot of decomposing over the winter months?

If you are in a cold climate, or you turn under the mulch & try to plant right away, the N will be robbed from your plants much worse.

Anyhow, long-term the mulch helps, but you will need to add a source of N also to keep your carbon & N balanced.

In general the stemmy fiber stuff (hulls, wood, stalks, cobs, & stems) is carbon, and the green or fruit/ grain part of plants (green leaves, manure, rotting friut, etc.) would be the N.

If you could work a legume (inocculated) into your rotation it would really help fix natural N. (Legume - beans, peas, clovers, alfalfas - they get a bacteria on their root that pulls N out of the air & places it in the ground for you.) You need that bacteria tho, if no legumes have been planted for a while the bean or clover won't form any on it's roots on it's own.


-- paul (, May 06, 2002.

Moderation questions? read the FAQ