First of all, as to what to add to pH the soil, I read a post on here at some point about someone who tried multiple different acids, and some worked and some affected the plants. I'll try to find that post. I would guess you could start by trying vinegar (acetic acid), which is about as mild an acid as you can get.
Steve_D wrote:(Proof to follow in a few weeks for the "photos or it didn't happen" crowd.)
As part of that crowd, I think I can speak for us all when I say that you may get a little more of a pass than most other people, as many of us have gotten plants from you and have a pretty good idea of your ability and integrity. That being said, I always enjoy pictures, especially of experiments like this one.
95slvrZ28 wrote:Does anyone know where the idea that VFTs need acidic soil came from? I'm starting to wonder if it's simply something that has been passed down because everyone has seen sphagnum peat moss as the preferred growing medium for so long. Knowing that a VFT naturally grows in extremely sandy soil, it would seem that they would prefer something closer to neutral pH...last time I checked non-soluble sand shouldn't magically make an acidic growing environment.
There's still some dissolved material there, no matter how little, and that's what defines the pH. pH is dependent on volume, that's true, so the less organic matter which is setting the pH, the smaller the change from neutral. Still, I would expect that there's enough matter there to at least roughly stabilize the pH from minor changes (trees falling, etc.), otherwise it would always be wildly fluctuating. Which it might, I guess. Hmmm. It would be a cool experiment to grow flytraps in hydroponic setups maintained at different pH's over time and compare growth.