Here are some basic tips for planning an outdoor baby shower:

Choose a location that is safe, accessible, and has plenty of shade or shelter in case of inclement weather such as wind, rain, etc.
Consider the time of year and the expected weather. Make sure to have plenty of water on hand and provide sunscreen and bug spray if needed in the summer months. Ohio is usually primed for outdoor evens by mid April.
Set up a covered tent area for gifts and a separate area for food and drinks. 10x10 pop ups for great for this.
Plan activities that are appropriate for an outdoor setting such as lawn dart games such or corn hole!
Decorate with elements that are appropriate for the outdoors, such as flower-walls, balloons, inflatables and more!
Make sure to have enough seating for all of the guests, either through the use of outdoor furniture or rent tables and chairs from a rental company.
Consider hiring a professional photographer to capture your event for memories!
Plan for any necessary permits for rentals, such as tent rentals permits or special event permits.
Don't forget to make arrangements for music, renting speakers is a great way to save money.
Make sure to have a backup plan in case of inclement weather or rent a tent with sidewalls.