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Minnesota([email protected])

Anyone here use it to heat up the soil?
I'm going to have my plants under unheated hoophouses, and am thinking about putting black plastic over the soil, around my plants(until they start to vine).
Do you think black plastic will make a significant difference in plant growth? Any negatives to black plastic you can think of?

Doug

5/17/2005 6:56:13 PM

Omaha, NE (N41-15-42 )

It'll heat it up during the day time. I'd use soil heating cables though. I tried them for the first time this year and I've been amazed this year at how well they do. I had a plastic coldframe structure over one of my plants, and even when the outside air temperature got below 40, the air temperature inside the frame was 10-15 degrees higher at night. Most self regulating heating cables have a set thermostat at 70F.

5/17/2005 8:15:25 PM

Belgium

I use black plastic, but no hoophouse(dont need one, its my soil temperature that is my problem, the air is fine). I didn't use it one seedling this year and I had to pull it because it stopped growing. I put another one in a few days ago and it has black plastic and is growing great!

Jake

5/17/2005 9:01:17 PM

Clear plastic will heat your soil even more than black.

5/17/2005 9:11:52 PM

Eveleth MN

I use it to keep the weeds down until the seedings can provide enough shade to kill the weeds.

5/17/2005 9:41:42 PM

Minnesota([email protected])

DJ,
Why does clear plastic heat the soil more? I thought black would absorb more heat.
Thanks for the replies so far. I would think heating cables would work great, but I won't be using those this year. I'm pretty low tech with my growing. Maybe down the road I'll use them. Therefore, I thought black plastic may be helpful.

5/17/2005 10:15:04 PM

Menomonie, WI ([email protected])

clear lets the soil absord the heat instead of the plastic.

5/17/2005 11:28:52 PM

Nikiski, Alaska 99635

Clear plastic as DJ and Linus have stated. Sure the black plastic gets warm but it blocks the suns rays from contacting the soil.There is little if any heat transfer to the soil. Clear allows the ground to absorb the suns heat and retain it, much the way your greenhouse works. Imagine if you skinned your greenhouse with black plastic, you get the idea. Clear plastic is used on the ground in interior Alaska for growing corn. If not convinced place clear and black plastic down and place thermometers 3 inches down under each one on a sunny day. Wait about 3 hrs. uncover both and quickly check the temperatures of both.

5/18/2005 12:38:21 AM

Minnesota([email protected])

I'm convinced. I'll give the clear plastic a try. Thanks D.J. for bringing it up(and to J.D. and Shannon for explaining it)!

5/18/2005 12:41:20 PM

Billerica,Massachusetts

clear is the clear winner.

5/18/2005 12:55:51 PM

Utah

.... now you tell me ! :)

5/18/2005 1:24:43 PM

Montoursville, PA

I was just following along. Think the basics are clear enough. Harr Har.

Another thing, to consider, is the upward motion or movement, of moisture under any plastic. In survival training we learned, to draw life saving water using plastic over so called dry desert sand. If conditions are not fairly damp down some six eight inches the roots will be encouraged, to go, where the moisture will be drawn to and the soil is warmer by the use, of any plastic. Then when the plastic is removed those roots are more inclined, to get cooked, because they are more developed closer, to the surface. Food for thought!!! Clear enough?

Fooling mother is indeed tricky. Done absolutely right one might be a winner. The key word is might if such practice is followed with a mulch, to further protect those roots from near by summer heat and drying winds.

5/19/2005 12:57:12 AM

White Plains, NY

Clear allows weeds to grow, black kills them.

5/19/2005 7:08:55 AM

Minnesota([email protected])

doc,
That's something to think about.

5/19/2005 11:56:48 AM

Billerica,Massachusetts

true: but when your after heat then go clear and pull the weeds

5/19/2005 12:49:03 PM