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Woodinville, WA, PNW zn 7b

http://www.gi.alaska.edu/ScienceForum/ASF4/412.html for the research on this.

I worked at the Agricultural Experiment Station at the University of Alaska - Fairbanks (1 degree south of the arctic circle)

Growers typically use black plastic laid down to warm the soil. But in northern climates clear plastic works best. You get the greenhouse effect through the plastic that warms the soil and then the heat can't escape throught he plastic layer again. Black plastic, although warm on the surface, actually shades the soil. The motto at the Experiment Farm was "Cool Heads and Warm Feet."

I plan to use this method in spring in Washington State where we get lots of light, but the soil warms in late June.

11/12/2007 7:15:44 PM

Rocky-r@stny.rr.com

Should I wet the composting pile of manure down before I cover? I have 2 loads of manure that has high levels of saw dust in it, which is underneath 2 more truckloads of good manure that is also breaking down but is free of sawdust. I dropped a shovel into my pile today and did feel some heat but the saw dist laiden manure was very dry. Any hints? I have the 4 truckloads covered with clear plastic so the greenhouse effect is working but I am concerned that the sawdust manure is too dry.

11/12/2007 10:14:58 PM

Santa Cruz, CA

Very interesting. Thanks for the post!

11/12/2007 10:15:34 PM

Picton,ON (j.vincent@xplornet.ca)

Any thoughts on white plastic. I had a good supply of free black plastic, and the !@#$%^ supplier switched to white.

11/12/2007 10:40:59 PM

Menomonie, WI (mail@gr8pumpkin.net)

white reflects and cools

11/12/2007 11:14:42 PM

Eddyz@efirehose.net

Rocky
Yes wet down the pile. It will reheat very fast and break down quickly if its wet. Be carefull it don't get too hot on you, Once she starts to cook, you'll probably have to remove the poly.
Eddy

11/12/2007 11:54:58 PM

Woodinville, WA, PNW zn 7b

Rocky,

The heating action of the compost does not depend on external warming from the sun. Compost cooks from the inside by the respiration of the bacteria. The heat is essentially bacteria farting.

So wetting is the best thing to do to get the sawdust cooking.

Sawdust is rather inert, and a good additive to compost that is too green and stinking to slow down the action a bit.

The hotter your pile the better it will break down residule chemicals and weed seeds. It gets around 160. Barns full of wet hay compost so hotly that they can catch fire (somehow) I've witnessed it firsthand.

11/13/2007 12:44:00 AM

Woodinville, WA, PNW zn 7b

Dear County Kid,

White is no good because it reflects.

I like to use painters' plastic. It's very cheap and thin. You only need it on the soil until summer warms things up naturally. Then I pull it and throw it away. Plus you want the running vines to be able to root at the leaf junctions and not be inhibited by the plastic.

11/13/2007 12:46:45 AM

Rocky-r@stny.rr.com

I took the covers off today to water it down and dropped the shovel in about 10 different places... WOW!! Was the steam and smoke pouring out the top of the pile! I still believe it was too dry, so I added molasses and water in 5 gallon buckets, about 50 gallons worth of the mixture. The bacteria will eat like pigs now! Thx for the tip Larry. Thx for the help also Eddie and Green Elephant.

11/13/2007 7:34:30 PM

Rocky,
now you have your N, your browns from that sawdust, the moisture is added,,,,if you want that pile finished by spring make the effort to turn it a few times this winter,,

the oxygen is required to feed those same bacteria you just fed with the molasses

11/13/2007 7:43:11 PM

Owensboro, Ky.

GE, one of the older organic growers, who used to frequent this site, suggested a dusting of corn meal (not gluten) to be added into patch prep. I miss Doc Gipe!!! Peace, Wayne

11/14/2007 6:54:20 PM

Menomonie, WI (mail@gr8pumpkin.net)

Throw a perforated drainage tube in the center and create a chimmney. Making an "L" shape the warm air rising will suck fresh air in.

11/14/2007 10:36:43 PM

Rocky-r@stny.rr.com

Once a month on the turning Dan? I assume by "turning" you mean move the pile basically to get the bottom stuff on top and vice versa..The perforated tubing is an interesting idea also.

11/14/2007 11:59:19 PM

Rocky, temps in the pile are the key. You want to shoot for 160F internal. Check inside that pile using a thermometer, when you hit that turn the pile and check the moisture, like you patch you want it "moist" not "wet". The perf pipe will work (better in a windrow configuration) but turning gets the outside to the inside in order to digest all the material evenly.

My subzero temps shutdown my piles last winter in Jan (see diary '06 and '07) Last spring I built 3 piles that were turned every 2 weeks and those were done in 14 weeks, these were added in fall prep. The original piles built last fall ('06) were finished and now are building a worm population. These piles will be added this spring and turned in with the cover crop.

In your milder winter that plastic is a good idea and may help keep your piles working all winter, I did learn that the piles that were exposed to more winter sun finished faster this spring. I had thought about trying covered piles this winter but time didn't allow for that experiment here. I did insulate one 10yd pile with straw in hopes that those worms will carry out thier activity this winter.

11/15/2007 6:25:21 AM

Woodinville, WA, PNW zn 7b

I used to spend a lot of energy turning compost piles. Now I do a two-year cycle, and never have to turn anything. Just take the two-year old pile and distribute onto the garden. If you have time and space for two compost piles, you can ease your workload considerably.

For consideration.

Jim
GreenElephant

11/16/2007 6:36:06 PM

Woodinville, WA, PNW zn 7b

<a href="http://www.gi.alaska.edu/ScienceForum/ASF4/412.html">University of Alaska Article</a>

This is a test to see if I can post links on forums.

11/18/2007 5:08:15 PM

Woodinville, WA, PNW zn 7b

Nope.

11/18/2007 5:08:47 PM

Colorado

I use clear plastic over c. piles in colorado.we have milder winter temps than midwest.The greenhouse/insulation effect keeps temps up compared to piles with no plastic.

11/22/2007 12:33:24 PM

Woodinville, WA, PNW zn 7b

It's always cool in spring in the PNW. I laid a 10 x 10 sheet of 2 mil painter's plastic (super cheap) on top of my ground. When the sun warmed it the temp of the soil under the plastic at a depth of 6 inches is almost 80 degrees. The temp of the soil without plastic is less than 60 (my thermometer won't go any lower) This method is how they get squash to grow in interior Alaska where the nights fall to the 40's all summer, but there's lots of daylight.

5/26/2008 9:47:03 AM