Re: Potting soil advice (newbie)
Any medium that contains tannins will leach it into water. This is how tea is made. As the peat dries out, it releases less tannin, increasing the pH. When it gets wet again, it releases more tannins, decreasing the pH.
Peat is used to hold water in the soil, which is why it is added to light soils. Here in NC, where our dirt is nothing but red clay, adding peat would be like grinding up a Shamwow and adding it to the mix. Bad idea. That is why I don't use it in my banana soil. I do, however, use it along with sawdust in my redwood mixes because they like acidic soils of 4.5 and wet, well-drained soils.
While it is true that I am new to bananas, the laws of science do not change. I suppose if you are growing a banana in river sand, you would need to add peat to retain moisture. In clay, however, it is a bad idea.