Answer: Developing a landscape plan is a great idea. You need to think about how you want to use the space, how you want it to look, and analyze the growing conditions so you can select plants that will thrive there. It is well worth putting some thought into an overall plan before you actually start planting.
Measuring the space and making a scale drawing (or using your plot plan if you have one) can help you in your planning. This shows you clearly how much room you have for a tree, for example, so you can select a specific plant that will grow to an appropriate size. It can also help you determine the order to do large projects, such as this year we will plant trees and add a patio, next year a walkway, third year something else.
Many people find it helpful to work with a landscape architect if there are substantial building projects, or a designer if you are primarily looking for help with selecting plants. Some will work on an hourly basis for consultations while some will insist on working up a complete plan.
You could also look at a book or two about design, one that is very straightforward and practical with sound advice is Landscaping for Dummies, it is available in many bookstores and libraries.
Your local nursery and county extension may also offer suggestions or materials or classes/workshops to help you in your planning. I hope this helps you get started.
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