by Jason Ross
Think of your garden plants like machines. You input sun, water and minerals and you reap squash, potatoes, corn and tomatoes. Pretty cool machine, right?
When you see just how MUCH food comes out of the ground, you’ve gotta stand back and wonder; how much of that plant mass is being pulled from the soil (compared to sun and water?)
The answer: a LOT. A ton of the plant mass comes from the soil, especially when you’re growing big plants like squash, corn, potatoes and tomatoes. Big stuff leaches more mineral from the soil, as you’d suspect.
The primary mineral pulled from the soil is Nitrogen. But, it takes a number of other minerals, such as calcium, iron and sulfur for your plants to access that nitrogen.
It’s relatively easy to get nitrogen into your soil. Amending with compost or spraying fertilizer will accomplish that. Our organic fertilizer of choice is Turboganic. It comes in a liquid form and stores indefinitely. We spray Turboganic around our plants once a week during the grow season.
But many plants deplete calcium quickly, leaving your plants starving for nitrogen, even though it’s still in the soil. Turboganic doesn’t deliver enough calcium to off-set the consumption of many plants (though it does deliver plenty of nitrogen.) My squash and tomatoes usually exhaust the calcium in the soil about three-quarters of the way through their big growth push. It’s obvious when that happens because we start seeing tomato blossom end rot and the leaves on our squash start getting a “burned” edge.
You might never experience low calcium, depending on your local soil. However, it’s the most-common deficiency, so I’d plan for it.
One might think: I can just add more egg shells to my compost and then I’ll have calcium! Alas, egg shells, even when ground up, take over seven years to break down sufficiently that your plant can up-take them as calcium.
About a month into our grow season, we start adding TurboCal once a month to the soil around our plants (liquid calcium from the same guys that make Turboganic) and that eliminates calcium deficiency. Whatever kind of calcium you use, make sure it’s in a form that can be immediately taken up by your plants.
At least once in our gardening experience, we’ve seen signs of low iron. When the green on the leaves begins to retreat toward the veins, there’s a problem with nitrogen up-take — which might be iron deficiency.
This all sound like guesswork, but it needn’t be. You can have your soil analyzed, before growing, to find out exactly what your deficiencies will be. Even though you will always need to add nitrogen and probably calcium during the season, at least then you’ll know where you’re starting. Just send a soil sample to a local university that offers soil analysis.
Bottom line: you will deplete your soil. Your second and third years will probably be worse, unless you amend your soil generously with compost and fertilizers.
Again, like always, this is not shit you’re going to want to learn after the SHTF, because the process of learning drastically reduces your garden yield. Grow now. Learn now. That’s the survival garden motto.