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New Bremen, Ohio

I know that oxygen availabilty is crucial to the plant's uptake ability, but I'm curious how many pumpkin growers monitor this? The correct Oxygen Reduction Potential or (ORP), can enhance the effectiveness of foliar feeds and pest control sprays by increasing the plant's ability to take them up. A ORP reading, when added to the PH of a sample, give an "rH value" which can be used to diagnose the biological condition of your soil. Too low limits your biological activity and consequent lack of humus-building. Too high results in oxidation of organic material and loss of carbon to the atmosphere, limiting nutrient availability to the plant. I've read this can be adjusted by hydrogen peroxide. Does anyone do this and what other methods can be used to control this? Is this another factor pumpkin growers should monitor?

2/15/2004 12:57:33 PM

Woodburn, Indiana

huh? LOL.

2/15/2004 2:46:17 PM

Menomonie, WI ([email protected])

If I had the money, and wanted the oxygen enough I would go with Calcium Peroxide. It is in a granular form a breaks up slowly like a timer released fertilzer.

2/15/2004 3:00:45 PM

Western NY

i've used calcium peroxide before. pretty neat stuff. get a soil test done first, i wouldn't reccomend it if your pH is over 6.7 or so, as it will raise a bit with calcium peroxide use. pretty good in theory, but i can't say as any success can be pinned on the peroxide, because of all the other oddball things i was trying. i may try it again sometime. expensive stuff unless you can get a good deal on it like i did.

2/15/2004 3:21:42 PM

New Bremen, Ohio

I guess the saying "There is no such thing as a dumb question" goes out the door anymore. Thanks for the intelligent reply Carlos. I thought this was an interesting subject that I haven't heard a lot with pumpkin growers and thought other growers might be interested also. I thought this was a learning tool for us. Sorry if you thought this was humorous Carlos.

2/15/2004 6:35:52 PM

Appalachian Mtns.

Andy....did you get some CP in bulk? All I can find on the Internet is the same old expensive Oxy-Cal but now they do have it in 2.5kg and 10 kg, which I don't think is near sufficient for my total patch area of 3000 sq ft. I read 1 tbsp per 1 gallon of soil?
I searched high and low last year for the food grade but never could get my hands on any.

2/15/2004 6:57:46 PM

Western NY

i bought a 10 kilo bucket of it, and divided it up with some other growers. i put about 1 or 2 pounds on 600 square feet, mixing it in at the 6 to 10 inch depth. i know a couple other growers just tilled it in at about the same rate. i got mine from a generous grower in canada who was able to track some down wholesale before that year's falls meeting. i forget what kind of a price i got it for, but i think it worked out to about half of what i would have paid if i were to buy it in the US at the 1 kilo size. there are some companies out there that sell it in bulk for farming, but they were'nt willing to deliver it to me in anything less than a tanker load, lol. i wouldn't worry about food grade vs. ag grade. i'm assuming food grade is more expensive. most of the stuff you will get is 60% calcium peroxide (the remainder is calcium oxide and lime, i believe). i just went and checked the label. it says 20 kilos per acre for the application rate, but as far as i know ther is no real science to back up this rate. i think it's just an estimate.

Andy

2/15/2004 8:18:07 PM

Key West, FL

Calm down Jeff, I think Carlos, like me, doesn't understand what you guys are talking about.

2/15/2004 8:32:56 PM

Woodburn, Indiana

i thought it was very interesting, just over my head.

2/15/2004 9:36:44 PM

Indiana

Jeff,
I can vouch for Carlos being a jackass since I have class with him.....but then again, I have to vouch for myself being one too.

Tom Beachy

2/15/2004 11:12:18 PM

New Bremen, Ohio

It's no biggie, I was just anxious for some pumpkin related comments and read "huh lol" and misread his intention. Sorry, you can tell Winter is taking it's toll.

2/16/2004 3:43:12 PM

Woodburn, Indiana

its time to get outside and plant!!

2/16/2004 5:46:49 PM

[email protected]

Vertigo,

I didn't want to comment on this until I had some time to spend on the soap box. LOL.

We did banter about soil oxygen quite extensively here last year. Most folks know that I favor a loose oxygen rich soil. First by adding copious amounts of decayed organic material. Then with the addition of the longer lasting (and non-reactive) calcined clay particals at rate up to one ton per 1000 cubic feet depending on existing soil texture, etc. If cost were no consideration, I'd like to try Calcined clay at still higher rates & may eventually make 2 tons here someday.

Last winter we spent a lot of time trying to find cost effective Calcium Hydroxide sources. CH is used primarly in the remediation of contaminated soils where the depth of the contaminants makes removal unpractical. Magnesium, Calcium, & to a lesser extent Hydrogen (peroxide) have all been used in these anaerobic scenarios with good success. The goal in these case is to scrub the contaminants free of the soil with aerobic bacteria. These are introduced with the oxygenating agent.

continued

2/16/2004 6:28:01 PM

[email protected]

Stainless steel probes are inserted, charged with a current, & electrical resistence is used to judge the Redox (reduced oxygen) Potential of the soil.

These tools could be used by growers. As long as a complete soil test has been done first of course. Salts & odd soil pH conditions would alter Redox Potential readings & make accurate interpretation of results difficult.

Most growers would find the cost of a quality meter out of reach. The cheap single probe units are simply not very accurate. And most growers already keep their soil in such good tilth that oxygen levels are probably not much of a factor.

But....for those who have access to such accurate test equipment & a source of calcium hydroxide....I think this would make a fascinating experiment. Especially if one were to compare fruit gains to real soil & tissue analysis to draw some correlations to the oxygen enriched biosphere.

I think it's a neat idea for someone has the resources to pull it off.

Steve

2/16/2004 6:28:12 PM

New Bremen, Ohio

Thanks Tremor. You always explain things very well and did it again. Have you heard about a ORP reader called a Orptestr and costs around $150? Is this the cheap single probe unit you mentioned?

2/16/2004 10:11:34 PM

Western NY

steve, can you comment on calcium hydroxide vs. calcium peroxide? any quality/price difference?

2/16/2004 10:36:34 PM

[email protected]

I searched the Orptester & found that it looks like a hand held single probe water tester.

http://www.process-controls.com/Metex/Oakton/ORPTestr_BNC.htm

This link offers several pdf files that weren't loading when I checked. I would first insure they offer a soil probe for the unit before buying one & also check the additional fees. The advertised accuracy was +/-5mV on a scale of -50 - 1050mV. That doesn't sound not too bad, but I have nothing to compare this to having never had field testing responsibilities of this nature. I guess that for the top 4-6" of soil a unit like this might not be a bad deal. If they offer similar accuracy using an affordable soil probe.

Andy,

We liked the calcium based oxygenators so much last year because pumpkins also require so much calcium. Magnesium Peroxide (hydroxide, dioxide, etc) might have offered too much Mg which might have knocked the ratios out of balance.

Calcium Peroxide seems like it should be easy enough to find since commercial bakeries use it to moderate oxygen in dough making. But we never really found a supply. I think we didn't try hard enough. I know it's also used to get rice started so Ag dealers in rice country should have it. Calcium Peroxide turn into hydrogen peroxide in moist soils.

http://www.fact-index.com/c/ca/calcium_peroxide.html

Calcium Hydroxide is also known as "Slaked" , "Burnt", or "Hydrated" Lime. It can be used for very fast pH changes (lower) in agriculture but is more commonly used by masons to improve the adhesion of mortar mixes especially to older existing mortar such as in making repairs.
Your dentist might also use it as a temporary filling right after a root canal but before the permanant crown is installed.

We wouldn't see the liberation of oxygen from hydrated lime that we're after & could really louse up the soil pH trying.

I still have no idea where to buy reasonable quantities of calcium peroxide at fair pri

2/16/2004 11:27:34 PM

[email protected]

Oh I screwed up earlier. I said we were looking for cost effective calcium hydroxide. I should have written "cost effective sources of calcium PEROXIDE". CH is very cheap & easy to find.

My bad.

Steve

2/16/2004 11:30:53 PM