Market Farming

[Steve Diver <steved AT ncat.org>]

There's several ways to transition from sod into cropland.

Tillage and cover cropping is an obvious choice. I'm
not sure what you can sow that late September in
Wisconsin, maybe winter rye or hairy vetch or annual
ryegrass.  Or just wait until late winter in 2007 to break
the sod open.

But if you like the cardboard method I'd view it as
a sheet mulch.

After you mow down the sod, but before you lay down
the cardboard, I suggest a surface application of rock
minerals, rock dust, some compost or manure, then
lay down cardboard, then cover with hay or straw.

The wet winter will soak the cardboard and the minerals
and compost will feed the soil.  Worms love to dwell under
wet cardboard.

You should be able to drill through the mulch with a portable
hand drill with attached mini soil auger and set in transplant crops
like cucurbits, tomatoes, peppers, or winter squash.

I don't see putting plastic over the cardboard.  If you're
going to invest in a synthetic mulch then I suggest geotextile
mulch (weed barrier) and use it instead of the cardboard.  

You can buy weed barrier in rolls that are 15' x 300'.
If you attach two strips together, that is 30' x 300'. 

In fact, you can use the weed barrier directly on sod.
Again, you'll need to focus on surface application of
organic fertilizer with calcium, phosphorus, and a good
nitrogen kick prior to setting out transplants.  You'll need
that mini soil auger to zip holes only 3" in width. 

You can grow amazing curcurbit patches on a block
of weed barrier like that.   You can also use it in
narrower widths and cover a typical 4'-5' vegetable
bed for the production of cut flowers and veggies of
all kinds.

The biggest unknown is when to do all that sheet mulching
with respect to winter weather and spring planting.  On one
hand you'd like some soil conditioning from the sheet mulch
and decomposing sod, and on the other you want it to remain
in place and suppress weeds through summer.  You might need
to top dress with more straw next summer, etc.

Hope that helps,

Steve Diver
Northwest Arkansas