It is difficult to obtain meaningful referrals from a forum that essentially has a world-wide audience :-)

My suggestion is to contact your local chapter of the ALPD (Association of Professional Landscape Designers). This is the closest thing to a nation-wide certification program for landscape designers and there are many highly talented designers that are members. I've attached a link that you can search for individuals by zip code.

As when hiring any professional, you will want to interview with respect to aesthetic compatability, ability to communicate easily and scope and acknowledgement of finished work, either via a portfolio or viewing actual properties.

Here is a link that might be useful: APLD member search

Hiring designers for your garden can help in managing the best designs that you wanted to plan.

Here is a link that might be useful: Love My home