Bwallace, what kind of soil do you have there? If it's clay, you might want to add the grounds without rinsing. If it's already acid soil (if you have pine trees, azaleasgrow well, etc., your soul is acidic) you still might be okay without rinsing. The best advice I can give is to call your county ag agent's office and ask a Master Gardener what you should do. I'm honestly not sure why you'd want neutral pH, but the literature I've read said rinsing would neutralize the pH. There's a lot online about coffee grounds as a soil additive, but your local Master Gardener would be a good source for guidance on your local conditions. That goes for just about any question you might have about increasing the yield from your garden. Another thing is to have your soil tested. Again, your Master Gardener can supply you with a soil test kit and instructions and your state Extension Service will test for a nominal fee and tailor their response to your soil conditions and what you plan to grow.