before we discuss such.. perhaps it might be to our advantage to know why you want to sterilize mother earth ...

rather than stabbing in the dark about a solution.. whats the problem???

i have often recommended sterilizing potting media.. but i have never heard to doing it to ma earth ...

more facts please

ken

See the same post on the organic gardening forum. Ken has the correct response - not a great idea to consider "sterilizing" garden soil for most situations, not to mention it is rather difficult to accomplish anyway. And certainly not with horseradish!!

Well, isn't solarization a form of sterilization? I've read that after sterilizing, the bad guys will be gone and the good guys will come back.

The reason why I ask is I have tried solarizing with not much success. Most of my garden areas are on the perimeter of my yard with fence on one side of garden and retaining walls on the other. Although I tuck the plastic in well and all, I think the soil isn't getting hot enough. Because when I pull the plastic, there's plenty of algae and weeds growing.

I know I have a strain of fusarium per S.D. County AG extension. I rotate my crops every 3 years and I've tried the solarizing. So(short of removing 4 feet deep of soil all around the perimeter of my yaed), I thought there mught be another way.

Will continuing to feed the soil organic matter eventually help overpopulate the bad pathogens with a GOOD microherd?

Kevin

Woo, have you reviewed your solarization method carefully? I ask that question because it's very easy to miss a step or two in the procedure. In your climate, if the procedure is followed correctly and is done at the right time of year, I would think that it would get plenty hot under the clear plastic.

same question, different Forum
http://forums2.gardenweb.com/forums/load/soil/msg1121161820217.html?31694

Here is a link that might be useful: same question, different Forum

rhizo:

I think so. I've tried it 2 times -- one with compost and one without.

Here's what I did--

))Tilled entire area to be covered.
2)Dug trenches about 8-12" deep along perimeter.
3)Totally saturated soil.
4)Laid single layer of 4mil clear plastic tucking in to the trenches.
5)Covered up edges of plastic with soil dug up from trenching.
6)Waited 3 months.
7)Uncovered areas and tossed any of the soil along edges in trash in case any of that soil was still tainted.
8)Swore some because my first though after seeing all the algae and weeds was that it didn't work.

If I can get a couple pics, I'll show why it's difficult to be efficient. I might have to wait until a friend comes by though. My cell phone camera sucks.

Thanks

Kevin

Solarizing soils can, temporarily, sterilize but if the "good" bacteria etc. will return why would the "bad" ones, the disease pathogens, also not return.
This is on the web site you linked before to Goldeb Harvest, " Having healthy soil and a good eco-balance in your yard allows nature to take care of itself. Keeping the soil in top condition is the number one way to have healthy, strong plants! Plants have naturally inherent abilities to ward off adverse conditions when living in healthy soil."
I have said the same thing many times only to be told by some non believers that that does not happen.

I have a strain of fusarium per S.D. County AG extension.

==>>> there are good and bad ones.. which do you have???

and what is the impact in your crop ...

and what did the extension office suggest you do about it???

ken

Ken:

Well, since the diagnosis even mentioned one and it was because I took them a sickly plant, I assumed it was a bad one. They didn't list the good microorganisms in the soil.

I believe it was the B strain if I can recall correctly.

I don't recall if they gave ANY recommendations. They MIGHT have mentioned crop rotation. But since I had already been doing this, I researched a tad and found out that solarization might be effective.

Kimmsr:

I assumed the theory is that after ridding of the bad ones, building the soil again with OM, the good microherd would flourish and the bad could be held at bay as long as crop rotation, non-infected seedlings and seeds, and proper garden sanitation were continued.

Kevin

Don't forget the importance of plant selection in preventing disease problems. Scientists continue to introduce new plant varieties bred to be resistant to the diseases that plague them.

Rhizo:

I have. I've even gone through the list of tomatoes available and there are SOME varieties that are resistant to fusarium 1, and then some that are resistant to 1 AND 2 and some even that are 1,2,3.

The thing is the more resistant a variety is to multiple diseases, the more likely that it's a determinate variety-- at least that's the trend I noticed. I think the list(that I saw) only had a couple of INDETERMINATE varieties that are resistant to multiple strains. Being here in zone 10 and the limited space I have, I prefer indeterminates.

Btw, does it sound like my solarization technigue is PROPER?

Kevin

Sounded like proper solarization. Has fusarium showed up again on plants in that area or are you just thinking it failed by the algae & weeds?

tj

P.S. Best place for horseradish is mixed with ketchup and put on polish sausage.

Woohoo, the success of the solarization depends on soil temperature, as you know. Time of year makes a difference, as does days of sunlight, etc. Did you keep track of soil temps? Sounds like you did everything right.

Horseradish and ketchup belong on fresh, barely warmed oysters and seasoned, boiled fresh shrimp. :-)

tj:

Well, I haven't had a plant tested again. But I have had plants show the same characteristics. And yes. The algae and weeds led me to believe it wasn't successful.

Rhizo: no temp keeping for fear of heat loss. I figured there's probably nothing I can do to change that -- it's not like I'm going to chop down my tangerine tree or move the house(both which shade portions of the solarized areas at some time throughout the day).

I agree with both of you -- love my self some horseradish. I just thought that since I've always wanted to grow some and solarization seemed to fail, that I could possibly kill 2 birds.

Wishful thinking.

Kevin

Was there condensation buildup on the plastic during the day when there was sunlight?
Was the plastic kept raised off the soil or did it lay on the soil?
As the sunlight heats the soil under the plastic that soil should be giving up moisture which would then collect on the plastic. That would be an indication that solarization is taking place. Most all sources about soil solarization I have studied indicate two layers of plastic, not touching the soil underneath, are needed.

Ok -- I said I'd try to get a couple pics to show why solarization is difficult for the areas I garden. So, here they are.

It would be easier if the fence wasn't there so I could just walk along that edge, tuck the plastic, and the cover with soil. But I end up trying to straddle the whole width with my feet. I'm sure it looks pretty funny while I do it.

Here's another area. That's a rectangular raised area that has the brick wall forming one "L" and the stackable brick forming the other "L". I'm thinking that the stackable sides "breathe" too much -- which would possibly not allow the soil to heat up to optimum temps.

Kevin

kimmsr:

Yes. There was condensation build up (for a while). One would figure that the condensation would keep on going, but slowly it dissipated. I have also read about 2 layers but not EVERYWHERE I researched. And I never read about the plastic NOT touching the soil.

Here's a small tutorial from UC IPM (a site for which you frequently post links).

I might try the soaker tape method it mentions.

Here is a link that might be useful: click here