Terraforming Age (aka Age of Terraforming) is my take on the classic natural decor genre.
Normally, you can't access most of the natural tiles and environmental entities in your standard playthough.
This unlocks a large amount of them for all your free building needs.

This mod adds growing versions of all of Nauvis's trees, locked behind the standard Gleba tree seed technology.
These can be farmed just like regular seed grown trees, no differences besides aesthetics.

Tiles have been added for most of the Nauvis grass and dirts.
(Note that due to technical limitations, these are not exactly the vanilla tiles but rather copies of them.)

Entity versions of many of the basic decoratives!
Now you can place little bushes or grass patches where you like.
Some of them are locked behind researching certain planets, respectively.

There are a few other changes, like trees being placeable on way more surfaces and tiles now. (Agriculture towers not included)
Want to build a huge garden on Vulcanus? Thats possible.

Of course there are recipes for all the different additions; everything is accessible in a regular playthrough.