North American Fruit Explorers mailing list at ibiblio

[Rob Halgren <halgren@msu.edu>]

> Date: Mon, 7 Feb 2005 17:10:58 -0600
> From: "Doreen Howard" <gardendiva@charter.net>
> Subject: [NAFEX] Was: Powdery Mildew control; Now: Solarization
> [...]
> A couple of things from experience about solarizing ground.  First, make 
> sure the soil in the top six inches is really moist.  Second, use timbers, 
> weights or anything heavy to seal the plastic.  The more airtight you make 
> it, the faster the soil steams.  Third, get a soil thermometer; don't try to 
> guess at temperatures.
>
> Solarization cleaned up problem ground for me so that I could plant peach 
> trees in a hot climate where blights and other fungal diseases are huge 
> problems with peaches.  My trees and fruit were disease-free with only a 
> late winter dormant oil spray and three applications of neem seed oil spray 
> at bud break, blossom fall and three weeks later.
> Doreen Howard 
>
>  

This is a classic technique in organic gardening.   If you do it right, 
you also kill most of the weed seeds in addition to soil pathogens.  I 
haven't gotten a chance to do it at the new house yet, but I would put 
the plastic on in the early fall on a patch of lawn that I want to turn 
into a garden (or plant a tree), and leave it on until June or so (maybe 
earlier farther south).  Never used a soil thermometer, but that is a 
really good idea.  If you leave the grass tall, or throw a bit of hay or 
straw down, you will also get some nice humus additions to the soil.  
Over the winter the worms and other critters will chew up all the old 
sod and whatever you threw on top, and after a few hot weeks of late 
spring everything remaining is nice and cooked.  And the real benefit, 
you can till the soil with your bare hands.  It really loosens up the dirt.

You can pretty easily bury the edges of the plastic.  Just make sure you 
get the entire perimeter, or it will blow away.  Landscape timbers work 
too, but I'd just flip about six inches of turf onto the edge of the 
plastic all the way around.  It isn't that hard, and you don't have to 
move heavy wood.

Anyway, the point of this message is that if you want to pick it up, I 
have a whole lot of plastic sheeting suitable for doing this.  When I 
re-covered my poly greenhouse this fall I salvaged some of the bigger 
pieces.  Really thick, and quite heavy.  I'm not shipping it anywhere, 
but if you are in mid michigan and want to come over and get some, feel 
free.  I'll be using some in the spring, but I have a lot.

Rob

--
Robert G. Halgren, Ph.D.
Associate Director, Center for Animal Functional Genomics
1205F Anthony Hall
Michigan State University
(517) 353-9136