Skip to Content.
Sympa Menu

market-farming - Re: Companion Planting in Sweet Corn

market-farming AT lists.ibiblio.org

Subject: Market Farming

List archive

Chronological Thread  
  • From: Alex McGregor <waldenfarm AT sprintmail.com>
  • To: market farming <market-farming AT franklin.oit.unc.edu>
  • Subject: Re: Companion Planting in Sweet Corn
  • Date: Sat, 03 Feb 2001 13:08:56 -0500


Jeffrey,

First a word or two about legumes and nitrogen fixation. Legumes grow root
tissue over
N fixing (rhizobial) bacteria they encounter (naturally occurring or
inoculated) as they
grow and feed these bacteria with sugar from photosynthesis. The bacteria
flourish and
establish large colonies in the roots inside nodules. These bacteria oxidize
Nitrogen
into nitrate, which they give off as a waste and the legumes use this.

Legumes are not altruistic. They will not feed these bacteria sugar if
enough nitrate
for them is present in the soil- it costs them about 1/3 of their sugar
production to
feed these colonies, thus limiting their growth. But they can grow and
reproduce
adequately in low soil nitrate conditions with the help of the bacteria.

And legumes don't exude the nitrates produced by the bacteria into the soil.
They use
it for amino acids, etc. for themselves. So, the only way to build N in the
soil with
legumes is to plow them in as a green manure crop before they form seeds and
feeding the
N processors in the soil. And, you must wait at least 2 weeks for the first
wave of
soil life feeding to subside before planting anything but another legume.
The reason is
that you will have an "artificial" N shortage in your soil. The sugars and
carbohydrates are easily assimilated and this initial feeding frenzy will use
all the N
in all forms and it will be in their bodies until lack of food causes a mass
die off and
the N gets released by the saprophytes (dead material eaters) back into the
soil food
web.

Planting something like pole beans with corn works because the beans' root
system is
smaller and shallower than corn and there's little competition for water and
nutrients.
(Not because of the misconception that the beans will feed the corn.) This
companion
planting works on small scales- I've done it in market gardens to save
trellising the
beans and to get 2 crops out of the same space. I found out the hard way
that I needed
to plant the corn first and let it get 18" tall before planting beans so the
beans
didn't smother and stunt the small corn plants when seeding them at the same
time.

And you're right about the problems with machine weed control and harvesting
interplanted crops. Your only option (that I know of) would be to plant a
legume as a
weed smother crop and hand pick peas or beans before combining the corn.

I don't know what part of the world you're in, but I would recommend you find
a regional
sust. ag. group and tap into their experience with what you would like to do.
Most
growers involved in these organizations are happy to help others and share
their
knowledge and successes freely.

A national source for info is ATTRA, 1-800-346-9140, M-F 8:30am-4:30pm CST.
Or:
http://www.attra.org/

They supply farmers with free information on crops and sustainable
techniques. They
have crop specialists on staff and a huge sustainable agriculture library.
I've used
them many times and found them very helpful.

Good luck and hope your crops do well!

Alex McGregor
Walden Farm





Archive powered by MHonArc 2.6.24.

Top of Page