This is getting into somewhat of a deep dive, but I think its important to note there are two different schools of thought when it comes to assessing soil for growth potential.
One is strictly reading the soil test, and just addressing the levels of nutrients to reach
sufficient needs for crop growth. This is "good enough" for most, and what many farmers use, and have used for years.
The second is addressing the soil structure first (Albrecht/Kinsey method), before addressing nutrient
sufficiency. The benefits are the right physical structure, to get the best soil architecture for tilth, water absorption and biological growth. What most (I personally believe) fail to realize, is that while trying to get the right nutrient
sufficiency or "enough of each" of each nutrient, they are essentially chasing soil structure or
soil balance (refer to the thanksgiving plate example), without realizing it.
Lets walk down that path for a minute.. If you work in reverse, and address
sufficiency first, you will either a) keep throwing money at your soil trying to get results, or b) will get there unintentionally, or accidentally. Many times the "results" may be good enough for most, so they never bother to correct their soil structure first.
Ultra simplified:
1) Get your calcium to 60% BS, minimum. Ideal soil has Calcium BS between 60% and 70%.
2) Get your magnesium between 10% and 20%.
3) Address your potassium (P) and (S) levels. These 6 (Ca, Mg, N, P, K & S) are your macro (turkey, potatoes on the plate) level nutrients in the soil. Ideal K levels are 3% - 5% from what I recall..
4) Address your micro (salt, pepper on the plate) levels.
Now addressing the issue at hand, there are ways to increase or decrease the levels of any of the macro level nutrients.
1) Short on Ca? Add high Ca Lime (As Skip suggested earlier).
2) Excess of Ca? N or S can remove.
3) Short on Mg? Add a Mg source.
4) Excess of Mg? S can remove (only when Ca BS > 60%).
@RepCity_BK - Reading your Test Results:
Soil Test #1:
- Ca is a touch high (above 80%), which is pushing your pH above 7.0. This also indicates slightly porous soil which would tend to not hold moisture as well (not so great if you're already limited on rainfall) as a more ideal soil structure.
- "Fertilizer" would reduce Ca (and therefore pH) somewhat. P & K to the least extent, followed by most N sources, followed by Ammonia sources of N as the most acidifying. The most acidifying sources are ammonia based - NH3 (knifed into ground), AMS (Ammonia Sulfate) or Ammonia Nitrate. Urea less so. Followed by P&K additions last. Physically nitrogen drops calcium out of the soil, delivering the chemical (lower pH) result.
- However you have the conundrum of wanting to use Nitrogen on a legume plot. May consider something with a higher N demand before switching back to a legume.
Soil Test #2:
- Mg is on the high range, but not terrible. Definitely driving your pH up. (Recall Mg drives up pH 1.7X what Ca will).
- Elemental S, or higher rates of gypsum could help drive some Mg out of the soil.
For food plotting purposes, you have great soil in plot #1. Anything you plant should flourish. Plot #2 pH is getting a touch high. You may not ever notice the P, Mn and Fe deficiencies unless you pulled some samples and did a tissue analysis..
BUT - You're really tweaking at this point.. A LOT of people have grown great rye and clover plots with less than you have!!
