Not sure about where the park is and definitely not sure about any garden; this was next to a gas station we pulled into in Quartzsite, Arizona on our way back to the big city of Scottsdale. The road leads somewhere but heck if I could see where. There are signs along the road that say Welcome and All Visitors Register At Office. I guess this is/was another RV campsite – Quartzsite is well known for them. When we drove into town we saw sign after sign about RV parks. Many were closed until October but a few were open.
Quartzsite has a population of about 4,000 give or take a few but during the winter (especially during January and February) that number swells to close to a million for the RV show, flea markets, and rock and mineral shows. It’s pretty darn cheap to camp in your RV in Quartzsite so maybe there is a camp somewhere at the end of this road.