This is a paid asset, but now you can download Desert Vegetation Pack Free.
Detail this asset from Unity Store: Original Link
Desert Vegetation Pack v1.0 (Latest version)
“If possible, please buy the package to support the developer”
With this pack you can make your own desert in no time. It contains 10 different meshes to create a desert just the way you want it. All of the meshes have Diffuse maps and Normal maps.
List of meshes:
– Cactus with 5 legs
– Cactus with 3 legs
– Cactus with flower
– Low green Yucca
– High striped Yucca
– Rock 01
– Rock 02
– Rock 03
– A ground plane with path and high-res texture as shown in the screenshot.