I know some hydrosol PH in GV:
Rose Hydrosol pH 4.1- 4.4; Tee tree:pH 3.9 - 4.1; Neroli pH 3.8 - 4.5; Lavender pH 5.6 - 5.9; Immortelle/Everlasting Hydrosol - pH 3.5 - 3.8; Chamomile hydrosol pH 3.0 - 3.3.