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Q: Human Hair and Bean Plant growth ( Answered,   1 Comment )
Subject: Human Hair and Bean Plant growth
Category: Science > Agriculture and Farming
Asked by: address-ga
List Price: $25.00
Posted: 26 Feb 2003 19:37 PST
Expires: 28 Mar 2003 19:37 PST
Question ID: 167671
How does Human Hair affect bean plant growth?  Is there any effect on
growth, taste, color,etc?
Subject: Re: Human Hair and Bean Plant growth
Answered By: chromedome-ga on 26 Feb 2003 23:36 PST
Hello, Address-ga!

Your question sparked a train of memories for me.  I grew up on a
house filled with gardening and homesteading magazines, and I remember
as a youngster reading with fascination about the strange things
people put into their compost.  One of these was human hair; I
distinctly remember a couple from (I think) South Africa who grew
tremendous sunflowers with copious quantities of hair.

So, having determined to bend my bedtime long enough to research your
question, I broke down your question into two separate inquiries. 
First, what is the current thinking on hair in compost (using hair
directly as a mulch in a garden is ineffective, since hair tends to
mat up and will not decompose unless it is incorporated into a
properly balanced compost)?  Second, do beans respond to the nutrients
found in hair?

The first question was relatively simple to answer.  A Google search
on the keywords "hair" and "compost" gave over 20,000 results.

This Australian newsgroup, for example, characterizes human hair as a
solidly useful slow-release nitrogen source: gives the practical advice that hair should be cut
up as finely as possible, and distributed throughout the pile in thin
layers.  They also note that cat or dog hair seems to decompose more
quickly.  Since you specified human hair I will not go any further in
that direction, except to note that some gardeners have found that if
pet hair is used animals may tend to excavate your compost pile
regularly.  The mastercomposter link is here (scroll down the
alphabetical list):

This site, a BBC 4 gardening-show transcript, indicates that the use
of hair has been a part of British folk wisdom for some time:

This site, from the United Nations University, demonstrates that hair
was traditionally used in China as well:

To see the remainder of the search results for yourself (there may be
other nuggets worth gleaning), click on this link:

So, to this point, we've established that a) hair is quite
compostable; b) it requires relatively little in the way of special
handling; and c) it is an excellent source of nitrogen, one of the key
nutrients required by most plants (and therefore present in most

Now then, let's ask the obvious question:  "Do beans benefit from
being given extra nitrogen?"

With most plants, this would be a rhetorical question...right up there
with asking a roomful of kids whether they'd like some chocolate. 
Legumes, however, are widely known to be "nitrogen fixers"; in other
words, they are able to extract nitrogen from the atmosphere and
introduce it into the soil.  In essence, they are self-fertilizing
where nitrogen is concerned.

Current research, however, demonstrates they are not completely

This paper, from the University of Nebraska-Lincoln, notes that "Dry
beans need 100 to 125 pounds of nitrogen per acre, in addition to the
plant's ability to fix nitrogen, to obtain optimum seed yield."  "Seed
yield," in this context, means of course...beans.

This paper, from the University of Saskatchewan, states that "Dry
beans are unlike most other pulses when it comes to nitrogen
fertilizer. Most pulses do not have a yield response to nitrogen
fertilizer, but dry beans are relatively poor nitrogen fixers. The
percentage of beans' nitrogen that comes from atmospheric fixation
rarely exceeds 50%. As a result, most dry bean producing areas
recommend fertilizing beans with nitrogen fertilizer."

The most detailed analysis I found came from a study published in
Ontario, Canada, in March 2000.  The study looked at factors such as
overall yield, seed size, and protein content for six bean cultivars
over a period of three years.  Their conclusion was that nitrogen
fertilizer "gave a consistent and significant yield increase."  To see
the full report, click the link below (note that this and the previous
document are in .pdf format, and will require the Adobe Acrobat

The foregoing have all dealt with dry beans.  The Manitoba government
report given at the following link, however, deals specifically with
snap beans, and offers similar advice.  One additional note however is
that excessive levels of nitrogen will cause the plants to produce
greater vine and leaf growth, to the detriment of seeding.

For commercial growers applying great quantities of chemicals, this
could be an issue.  For a home gardener applying a compost containing
nitrogen, it should not be a factor.  Still, you should be aware that
many of these sites recommend the application of any desired
fertilizer in the spring, at the beginning of the growing season, to
avoid this.

This site from the University of Georgia, in addition to providing
good "nutshell" information, is lavishly peppered with full-colour
photos demonstrating the impact of various nutrients including

This is, unfortunately, the closest I've come to finding any
examination of how nitrogen affects the colour or flavour of the beans
themselves. However, beans - like any other edible plant - should
repay proper nutrition with attractive, well-flavoured produce.

Search Strategy

Since I've been detailing my search strategy throughout this answer, I
will not repeat myself here in the summary.  I will, however, provide
you with links to two authoritative sources which may be able to
provide you with more-specific information.

Organic Gardening magazine has been published since well before the
Second World War, and is still going strong today.  Their website, at

includes a gardeners' forum which you may use, if you wish, to request
additional information from experienced gardeners continent-wide.

The Mother Earth News is a relative newcomer, with only a three-decade
track record.  A leading source for gardening/homesteading
information, their website may be found here:

They also maintain user forums (fora?) in which you may seek more
detailed information.

Thank you for your question; your offbeat inquiry has given me some
entertainment in an otherwise quiet night.  If I have been in any way
unclear I'll be happy to amplify on any of the above.  I trust that
your first experience with GA has been a satisfactory one, and we'll
look forward to seeing you back again.

Subject: Re: Human Hair and Bean Plant growth
From: journalist-ga on 26 Feb 2003 20:07 PST
From what I discovered in my quick searches for you, eating beans will
help in human hair growth but human hair doesn't help with bean
growth.  There are claims of human hair repelling deer and moles from
a garden which could, of course, contain beans.

I did began wondering, though: If hair was sprinkled on bean plants,
would you have to shave the beans before eating them?

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