First of all, you have a beautiful landscape and have clearly done a lot of work. I do not have a plain yes or no answer. There is some background that you would need to know about your yard. If you had back fill brought in for different parts of your yard you would want different soil tests. If all the soil is native to the area and similarly treated it could be combined in one test. This could include the lawn if soil has not been brought in to fill the landscaping. Each section of your property with different types of soil or that has been treated differently would need it’s own test.

Here is a bulletin with more information on soil testing. There is also a link in the bulletin to order soil tests online. .

https://www.canr.msu.edu/resources/dont_guess_soil_test_get_your_home_lawn_and_garden_soil_test_kit_today

You can get soil tests in person at the local county extension office. You can find information on your local office here. You should call ahead before stopping in to make sure of availability. https://www.canr.msu.edu/charlevoix/county-extension-office

Here is a short video with instructions on doing a soil test. https://www.canr.msu.edu/videos/home-lawn-and-garden-soil-test-mailer