Yeah! Looks cool; but, what does it smell like?
Can I lick dat roooock?
I do not 3D print, but i do have some basic knowledge of it? I am not a ~~lawyer~~ printer, YMMV.
I have heard that some materials can be smoothed over using acetone vapour; what about wiping the finished print to smooth over open pores on the surface of a print?
Alternately, since it's not a flexible material what about applying something like 3M never wet?
Is the rocky area underperforming in terms of growth? Consider xeriscaping! Use drought and heat tolerant plants like succulents to fill in and color up an otherwise uninhabitable area