I'd say at least 2lbs per gallon of mead...just as a starting point.
also be aware that peach flavor/aroma is REALLY hard to get to come thru in the final product. its such a delicate flavor and aroma that its hard to get enough of it in there.
Primary: English Mild
On tap: Pale Ale, Lancelot's Wheat, English Brown Ale, Steam Beer, HoovNuts IPA
Bottled: MOAM, Braggot, Raspberry Melomel, Merlot, Apfelwein, Pyment, Sweet mead, Cabernet
Gal in 2009: 27, Gal in 2010: 34, Gal in 2011: 13, Gal in 2012: 10