If you need help redesigning and keeping up the landscape of your yard then look for a landscaping contractor. They should offer the artistic vision and the capability to fulfill your vision.
As you consider a landscape contractor to help you, you will want to have a plan of your own even if you know it will likely change to some degree after the professionals look at it. You may not be at all artistic but you can write down the types of plants, flowers, and shrubs that you like. You can cut pictures out of gardening and landscaping magazines to show what you like as well.
As you start looking for a landscape contractor, take your plan with you when you visit the various businesses. If they do not pay much attention to your ideas then you should definitely not hire them. You do not want to have a landscaper who only has a mind of their own and is not willing to consider your ideas. They might want to help you tweak your plan, but they should do this in a way that will help you to see the reasons why their ideas will work along with yours.
As you visit the various contractors you should also ask to see a portfolio of their work. This will help you to see how a contractor has a hands-on ability to fulfill the vision that you have.
Ideally as you look for a landscape coordinator you will find one that is also a landscape architect so that another contractor will not need to be hired to supplement. If a landscape coordinator chooses to consult with another professional on his own that is fine, but you should only have to pay for the professional you hire unless you and the one you hire agree otherwise in the contract.
After looking at the portfolios and speaking with a variety of contractors hopefully you will have found the one that fits you. All artists have a style that they excel at, so it might take some time to find the landscape professional that excels in the style that you appreciate and would like implemented at your home.
Do not cut corners and hire someone that does not have proof of their ability to design and implement a landscape. The outside of your home is what will be inviting to your visitors and also helpful if you decide to resell your home.