Ph of used cofffee grinds ?

mrtom

I use coffee grinds which I stir & mix in a watering can for a few days before applying to plants. My Research tells me :
Nutrient content? The kind of coffee grounds a typical homeowner would produce or obtain are around 1.5% Nitrogen. There's also a lot of Magnesium and Potassium, both of which plants really like; but not a lot of phosphorus (the "fruiting and flowering nutrient") or calcium, a mineral that many plants crave, and whose lack helps explain that recalcitrant acidity.So mix those coffee grounds in with some lime or wood ash. We can't recommend their raw use; the acidity could be high enough to damage even acid-loving plants.
However another source says:
Brewed coffee grounds have a pH of between 6.5 and 6.8. This is almost neutral. The acidity angle has been misinterpreted for years.
Which is correct?

papu

Get some litmus paper or a pH Meter and test it for yourself.