All gardens should have the boundaries well constructed whether building a wall or a fence . This ensures security and a defined edge to the garden . A poorly constructed fence can cause damage to plants and other garden features if it is poorly constructed and has to be replaced.
These images show a well constructed fence we recently erected and a fence we had to replace which blew down after a few months . One of the photos shows one of the posts concreted into a plant pot !!!
Employ a well respected accredited landscaper , get the job done right the first time . The cheapest job can often end up being the most expensive job .