Our nonprofit organization has a 24 ft RV that we use for outreach. We regularly park the vehicle next to our Experimental Community Curbside Garden that we have been developing for approx. 2 years. In addition we do neighborhood watch.

On several occasions our neighbors across the street parked three vehicles in such a way as to obstruct our outreach vehicle from parking next to our Experimental Community Curbside Garden (ECCG). Their actions are becoming a harassment. What can we do, if anything to get them to stop what they are doing?

You can talk to them and ask them if they have any concerns about your RV parked where it is. Mediate this before going to the police. But if you cannot come to some understanding or agreement with these neighbors, then you may need to involve the police. At the very least, check your city ordinance about parking.

I'd check your local parking ordinances, in most places your RV is illegally parked if it reaches past the end markers. The neighbors are probably annoyed by such a large vehicle across from their property, I might be too so try another location a half block away.