Soil and water test advice

[organic_john]

Hello all,

I'm wondering if I post a soil and a water test, could I solicit some advice?

In 2011 I'll be a first-year commercial grower in VA. Going certified organic. I'm growing on an acre. Had my first soil and (irrigation) water test done last month.

According to the tests, I think my soil ph is okay. I also think I'll have to lower the ph of my water. Beyond that, I'm not sure what I may, should, or must do!

I've approached some non-Tomatoville experts, but they know conventional growing. They say since I'm organic I should consult with an organic nutrient supplier. Which of course I will do. But I'd prefer not to be at the supplier's mercy. As it is, if he tells me I have to buy x, I won't know enough to argue.

John

[fortyonenorth]

Go ahead and post - I'm sure you'll get some very useful feedback.

[organic_john]

Thanks. I will be growing on approx one acre. The land is on my property. I've owned it three years. Previous crops have been hay, from about 2000 to this year. I'll have a small tunnel on the acre for early tomatoes, but most of the area will be open field. Tomatoes will grow under plastic, with drip irrigation.

My biggest problem is determining what nutrient to apply, and how much, and when, and by what method (foliar, drip, etc?). I'm planning on plant tissue analysis of course, but I'd naturally like to have the soil and water prepared the best way, however that may be, when I plant.

The lab offered general recommendations on the report. But it didn't specifically tailor them to me. For example, for pre-plant the soil test advises applying P205 and K20. But I'm growing organic, so... Do I just find the organic equivalent of that nutrient?

Ideally, I'd like to know what I should do now; what I should do in the spring; and what I should do over the course of the season.


I'll be offline for the rest of today but I'm coming back tomorrow. I'm more than happy to offer any other information--pictures, etc. Thank you again for your help, I do appreciate it. Best wishes!

John

[Stepheninky]

Your water PH is 7.6 and specifically for tomatoes 6-7 PH , for hydroponic gardening 5.5-6.5 but that last set of numbers is for soil less water based growing so it does not really apply to dirt farming. Your soil PH is 6.4 which looks really good.

I am not a commercial grower or tomato pro just an educated idiot so maybe someone else will chime in but if it were me I would leave it alone to be honest. Your values are close enough on the water that any chemicals or additives would be a pain to keep in check and what you put in the water will end up in the ground so long term it could also effect your soil PH which IMHO is spot on for tomatoes.

With that said one cheap and affordable organic way to balance water PH is to use plain old baking soda, to lower ph you have to use acids and too much of the chemical could actually burn or damage plants. Baking soda can be used to help neutralize an extreme acid or base, but again in your case I honestly do not think it would be of benefit.

[fortyonenorth]

Regarding the soil test, the two things that jump out at me immediately (and these go hand-in-hand) are the % organic matter and the CEC (Cation Action Capacity). Are you familiar with CEC? It's the ability of your soil to hold nutrients. Think of it as a bucket - the larger the bucket (CEC) the more nutrients it can hold. Adding organic matter will raise your CEC. The ideal % organic matter is somewhere between 4-10%. I would recommend planting a cover crop and/or adding composted manure. I assume it's too late to plant hairy vetch - even in Virginia - but you could still plant winter rye. That would be a good start.

Your "Percent Base Saturation" numbers are in the ballpark. K is a bit low, but not dramatically. Mg and Ca should equal about 80% - some sources cite 68% Ca and 12% Mg as "ideal." Some of your trace minerals are high, but I assume this is because of the low % of organic matter in your soil. As your % OM and CEC numbers rise, I think the trace numbers will fall into line. Boron is a bit low, but it's easy to over do it, so you should do some research before adding it to your fields.

I'm not an expert on this, but I think your chief concern should be to build organic matter. Since you're doing this as a serious pursuit, you should really consult an agronomist for recommendations. It's not expensive ($30-$50). There are plenty of independent agronomists out there who aren't pitch-men. If you'd like any recommendations, send me a PM and I can suggest a few.

Good luck!

[organic_john]

Stepheninky: Thank you for the idea about baking soda. I had not thought of that. Someone previously recommended powdered citric acid, 9 ounces per 100 gallons via a proportional injector, which would reduce the pH by about 1 full point. I guess maybe baking soda could do the same thing?

fortyonenorth: I'm not familiar with CEC. I'll read up on it. You make a good point concerning organic matter. I probably should have already planted a cover crop. Maybe if I get on the stick now I can get winter rye going. I'll also send you a PM, thanks.

[wmontanez]

Actually baking soda is a base and would increase the pH and total alkalinity of the water. If the pH less than 7 (neutral) then would be usefull (wood ash also works in that sense to increase pH of the soil plus adds calcium, phosphate, boron etc). When the pH is above 7 you want some acid.

I am not a commercial grower just a hobby organic gardener. The total organic matter is low at 2.2% try to increase to at least 5% by adding compost and plan on adding green manures in the future to increase the organic matter after the initial amendments.

www.umassvegetable.org/soil_crop_pest_mgt/soil_nutrient_mgt/soil_basics_I.html


This link is useful information about soil basics from my extension office. That material should give you some fundamental knowledge for the future.
These guys at UMASS-Amherst send at least organic amendment recommendations with their soil test analysis. Perhaps you could consult them. Good luck with your organic farm!

[organic_john]

Thanks, I will check out the info. Maybe in the future I will work one plot with compost and amendments, etc, as I farm another. That way I'll rotate and have a jump on the following year.

[RinTinTin]

@ wmontanez: Thanks for the link. That series of articles pretty much covers the basics of soil management. They manage to boil down into a few pages what an entire book would provide. Another fine example of why I always encourage people to visit their local Extension agent: most of the information that you can buy in books, is available for free from the extension office.

@ organic john: good choice. What land is not needed for this year's crop should be put to use growing organic matter and nutrients for the future. Cover crop seeds are one of the cheapest and most beneficial investments you can make in your land. Your land is working for you even when it is not working for market.

[casino]

Hi, I am a backyard gardener and from my experience I dont worry too much if my soil PH is off a little from the ideal. What I find important is the incorporation of organic matter, trace minerals and Mycorrhizae fungi.

Mycorrhizae fungi form a mutualistic relationship with the roots of most plant species (and while only a small proportion of all species has been examined, 95% of these plant families are predominantly mycorrhizal). Mycorrhizae fungi does not work on plants in the cabbage family but the results are very dramatic in tomatoes.

Try a "google" search on Mycorrhizae fungi and read up on it. At first I was skeptical about my living soil needing Mycorrhizae fungi but after using the product the difference in my plants compared to my neighbors N-P-K chemical garden are amazing. On baking soda, personally I would not use baking soda treated water when watering my tomatoes. The baking soda will kill the existing beneficial Mycorrhizae fungi. I do use baking soda, one level tablespoon per gallon of water to spray on the leaves to help prevent air borne disease like early blight and late blight and thats about it. No soil drench. I am no scientist but I find nature is very forgiving when you feed the soil living organisms instead of trying to change the soil PH through chemestry. IMHO a little cow manure and compost goes a long way.

[wmontanez]

Rintintin: my pleasure. Check ACRES magazine, MotherEarth news and Rodale farm trial website, very good information and also free!

casino: I am also a backyard organic vegetable gardener and have been adding mycorriza innoculant + compost to my soil. It's part of the regenerative organic approach I follow to try to restore soil fertility in my "farm" because frankly my soil was dead when I moved here 3 years ago. So far I can see the results with tomatoes and peppers, they do amazing.

During winter it's very important to have covercrops to give mycorrizal fungi a host root system so they stay alive and healthy for next season. The mycorriza produces glomalin that forms aggregates that will improve the soil texture over time, helps with moisture and nutrient retention. And on top of that sequesters carbon that will improve your soil too. So is a win-win.

Organic John: I like your comment of using a plot for farming and one plot for building your soil. Use covercrops that help you twice like a legume (nitrogen fixation) and a fast growing cereal then incorporate as green manure to increase your organic matter next season. My favorite legume for that is cowpeas, plenty of foliage, nice peas to eat and thrives in poor soil

[organic_john]

Thanks wmontanez!