See, with synthetics, you have chelated (salt-bound) nutrients that need to be in a proper pH range for the plant to take up. With organics, you don’t feed the plant, you feed the soil. The soil should contain microbes, mycorrhizae, and optionally, trichoderma. And the bacteria eats and decays the organic matter, shitting out what the plant can take up, regardless of pH. pH only matters in organics if there are inhospitably wide fluctuations that would cause root issues anyway. Think 7 for your basic limit and below 5.5-5.8 for your acidic limit. Maybe even down to 5.0, but I’d try to avoid going that low.