Help with Soil Test Results

[mysidx]

Hi, I got test results back from the sample I took from my back yard. I plan to make two more tilled raised beds for tomatoes and based on the results I would like to know what I should or shouldn't add to the ammendment proccess to optimize tomato growing. The results do tell me what they think is high or low for tomatoes. Here are the results:

ph (1.1) 6.35 Optimum

Phosphorus, ppm 14.15 Low

Potassium, ppm 58.97 Low

Calcium, ppm 918.97 High

Magnesium, ppm 319.69 Very High

Sodium, ppm 90.15

Sulfur, ppm 11.27 Low

Copper, ppm 1.00 High

Zinc, ppm 2.18 Medium


Rob

[dice]

Nothing on nitrogen?

Potassium sulfate, soft rock phosphate at a glance. Avoid
epsom salts and dolomite lime (avoid adding more magnesium).

[mysidx]

Originally Posted by dice

Nothing on nitrogen?

Potassium sulfate, soft rock phosphate at a glance. Avoid
epsom salts and dolomite lime (avoid adding more magnesium).

This test was done by the LSU Agriculture Center, and nitrogen was not listed. So basically all I need to add is some fertilizer, and soil structure?

[fortyonenorth]

Originally Posted by mysidx

This test was done by the LSU Agriculture Center, and nitrogen was not listed. So basically all I need to add is some fertilizer, and soil structure?

In the short term, that's probably your best bet. Your soil test is a snapshot of what you "have" now - anything you add to build your soil structure (e.g. manure, compost, peat, etc.) will alter it's mineral profile, so you should test again in the fall after you've amended.

As Dice suggested, Potassium sulfate (0-0-50) along with soft rock phosphate would be a good combination of amendments. If you go this route, you'll probably need to add some nitrogen, too. Alternately, you could use a balanced organic fertilizer, like a 5-10-5 or a 10-20-10. I would NOT recommend a tomato-specific fertilizer, though (e.g. TomatoTone) Many of these contain Calcium and Magnesium, which you do not need.

In addition, I would suggest adding a source of micronutrients such as greensand, kelp meal and/or Azomite. Your choice would depend primarily on availability and price.

As a side note, most labs don't test for Nitrogen unless requested. The reason for this is that N levels are very dynamic - meaning they can vary significantly day-to-day depending on soil temperature, pH and other variables.

[mysidx]

Thanks Fortyonenorth, that was very helpful information.