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Elementary Science Education

Is burning fertilizer dangerous?

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    • #472



      We did a demonstration where I put a candy in a mason jar and some green sand (fertilizer) in another dish. I then used my creme brûlée torch to try burning them. The green sand did not burn. The candy was burning but not catching fire. Then… whoops! The mason jar actually exploded. It did not hit any of us.

      Question #1: Was the mason jar explosion just a dramatic example of expansion?

      Question #2: Aren’t some fertilizers explosive? It might be worth mentioning what types are safe to use and what ones are highly flammable.

      Question #3: We compost, so my son sees us feeding the plants biological materials. Doesn’t that appear to kids as if the plants are absorbing/consuming materials from the plant kingdom?

      Thank you in advance.

    • #473

      Bernard Nebel

      Heating glass in one spot causes expansion of that spot while the rest does not expand. This creates stresses that will shatter the glass. I suspect that is what happened.

      Inorganic fertilizer, (any kind) in the amounts normally used poses no danger of fires or explosions. It is masses of many tons under unusual conditions and/or mixed with other things that may become hazardous.

      The idea that plants feed on soil in a manner similar to animals feeding on food is a rather natural assumption and one that is not easily disproved. It takes modern science and sophisticated experimentation to do so.

      The elementary level observations that have bearing are the facts that we don’t find trees growing in holes, and considering why plants have leaves. Then we need to make the distinction between an organism obtaining energy and its obtaining the necessary chemical elements (N, P, K, et al). Animals get both from food; plants get energy from light, but the get the N, P, K, et al from the soil. Thus, plants grow well on just water containing a solution of the nutrients–hydroponic agriculture.

      Compost–I am glad to see that you do compost–provides two things: First, it provides an ideal environment for roots and this environment helps plants prosper. Second, as as compost breaks down it releases the same N, P, K, et al elements that other plants absorbed. Thus, it serves as an ideal slow-release fertilizer.

      Some people claim that vegetables grown on compose-rich soil taste better. However, to my knowledge, it has yet to be proven that plant absorb any organic compounds from compost.

      Bernie Nebel

    • #474


      Thank you for taking the time to write such a thoughtful reply!


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