The barn was the first thing I made for my scene, roughly following a Blender Guru tutorial on making houses. It was what started my whole idea, as a farm seemed like an environment that had plenty of different things I could include to make the scene interesting. I modelled it in Blender, using textures from BlenderKit I modified to fit my vision.

Here's the full 3D Model, without textures. I left the inside empty to make rendering quicker, and because you wouldn't be able to see it from the outside.

Next was the corn, which would be useful for adding atmosphere to the farm and filling any blank areas. I used a simple subdivided and stretched cube, and then moved onto the texture. I used a voronoi to add dots across the surface, gave them colour with a colour ramp, mapped bump to those dots, and once put all together it resembled corn enough to not be noticeable from a distance.

The water was another important aspect I felt would help fill space, and the river was a good way to make the islands feel more connected and whole. Here's the nodes for the actual water texture. It uses one shader for the water and one for the the foam, mixing at the end into a singular material.

Here's the water moving. The movement was difficult to get to transition between each body of water, without using actual liquid simulations, but I think got it to look as good as I could.

The pen was a good addition, making the barn look more lively and farm-esque. I modelled one haybale and duplicated it around the scene in different places to fill up the scene.

The textureless hay model. I just added some distortion to a cube, stretched it out and then selected a loop around and duplicated it to make the bindings around the bale.

Here's a good close-up of the barn in place, with the corn and river in the foreground. This render was to make it appear like a normal scene, just a simple little farm, without revealing the floating islands.

And here's the final scene, showing off all the elements together. I quickly made some roots to connect the islands as I thought it made it look more "natural". Everything was made in Blender, with textures made by hand, except a couple which I took from BlenderKit. The tree was also taken from BlenderKit as it was a last minute addition to brighten up the scene, but everything else was modelled by me.