most things i have read and products say the best range is 6.2-7.0 ph for foliar. so thats a decent size range as most nutes will keep you right in there.

not to add more fuel to the fire but has anyone ever heard of a product called indicate5? it's used in rose gardening and supposedly 4.5-5.5ph is the best for foliar absorption... so much so that a wetting agent is based around visually cuing you to the proper ph; it turns pink at the right ph.

i wouldn't use the stuff past veg as i don't think it's been cleared or tested as a wetting agent but it's just some food for thought... i've been meaning to do a test comparing the indicate 5 to dutch master's penetrator/saturator but i've yet to have the chance

If it means anything to anyone - Dutch Master RECOMMENDS to NOT adjust your ph when using their foliar products.