As The Society of Garden Designers says:

 

"Good design doesn't fade.  From the start, we designers have to project forwards to understand how a design will develop and age, acquiring an attractive overall patina of maturity rather than sliding into disordered decay.  Nature and clients are beyond our control.  But we can control our decision-making, our communication with clients and contractors.  In short, we can do our very best to focus on each and every aspect of the design to give our gardens longevity."

 

 

When deciding what is reasonable to spend on a garden, spend what you have spent on your kitchen.